Insulation of the attic from the inside, if the roof is already covered: the order of work and useful tips. Do-it-yourself insulation of the attic roof Additional insulation of the attic from the inside

To ensure a comfortable stay in the attic throughout the year, homeowners need to purchase a high-quality type of insulation and mount it, taking into account all the nuances. The roofing cake will only last a long time if the attic roof is properly insulated.

Features of mansard roof insulation

If the technology for arranging insulation is observed, a microclimate favorable for human habitation is created indoors. On cold days, it will be warm and comfortable, and in hot weather, the air will not overheat due to the presence of thermal insulation.

Before insulating the roof of the attic, it does not hurt the homeowner to understand the features of the arrangement of the roofing pie and purchase high-quality tools and building materials.

The process of thermal insulation of mansard roof structures has much in common with the insulation of other types of roofs for private houses, but they are subject to special requirements. This is due to the fact that the walls of such premises either closely adjoin the slopes, or are formed by the slopes of the roof and the gables of the structure. As a result, the air in the attic gets too hot on hot days, and cools down quickly on cold days.

The structure of the roofing pie of the attic roof in the direction from the inner layer to the outer looks like this:

vapor barrier;
insulation;
ventilation gap;
waterproofing;
finishing material.

The presence of all of the above layers, according to the attic roof insulation technology, is mandatory, since each of them performs a specific function.

How to insulate the roof of the attic correctly

Increased attention should be paid to ventilation and thermal insulation, since the quality of their arrangement depends on how comfortable it will be on the attic floor. When choosing a heater, thermal conductivity is taken into account - it means the ability to direct heat into the room and in the opposite direction.

The lower this indicator, the better the material will be able to protect the attic from the loss of thermal energy. This means that to ensure the desired level of thermal insulation of the roof, it will be possible to mount a smaller layer of insulation.

Most of the heat in a heated room is lost through the roof, since the heated air always rises. It penetrates through the layers of the roofing cake and moves in the direction of the coating, on which the snow layer lies in winter.

At sub-zero air temperatures (less than 2 degrees), snow, due to its porous structure and the presence of internal air pockets, performs the function of an external heat insulator.

If the heat loss due to the roof is large, the coating material is very hot, and the snow layers begin to melt. Then, as the temperature drops, the resulting water turns into ice. The presence of a frozen crust is very dangerous for the roof surface - the load on the roof structure increases significantly. When the mansard roof is properly insulated from the inside, the snow does not begin to melt on it in frosty weather.

In the summer heat, excess heat gets into the attic from the roof, and even the air conditioner will not help to ensure a comfortable temperature in the room. This problem can be avoided by installing a high-quality thermal insulation layer from the inside of the roof. Of course, in the attic floor the air temperature will be higher than in the rooms located below, but this circumstance will not cause discomfort.

Mansard roof ventilation device

Roof insulation above the attic needs a special approach, which is explained by the peculiarities of its design. Ventilation of a standard roof is provided by the presence of an attic equipped with dormer windows. As for the attic, its ventilation space is only 10-15 centimeters.

When arranging such a roof during the installation of the roof pie, it is important to correctly make the ventilation gap. This space between the layers of waterproofing and insulation should help remove excess moisture and prevent overheating of the roof in winter and, as a result, the appearance of an ice crust.

As a result of the arrangement of ventilation, the entire structure will be provided with protection, which will extend the operational period of the roof elements. On hot days, due to the presence of a gap, heat is partially removed from under the roof - this circumstance helps the air in the attic not to overheat.

The choice of thermal insulation material

In preparation for laying a roofing pie, before insulating an attic with a sloping roof, you need to choose high-quality material. The thickness of the future insulation and the number of layers of insulation depend on its technical parameters. On the domestic market of building materials there is a huge selection of products for roofing.

Among them, the most popular are:

mineral wool;
extruded polystyrene foam;
glass wool;
polyurethane foam.

In some cases, foam glass may be used. For internal insulation, natural materials such as wood chips, seaweed and others are used.

Priority in choosing

When choosing a heat insulator, several technical characteristics are taken into account:

coefficient of thermal conductivity;
environmental friendliness;
fire resistance;
moisture resistance.

Experts consider the best choice for insulating a mansard roof to be a material with a thermal conductivity coefficient of 0.05 W per square meter or less.

The higher the moisture resistance index of the insulation, the longer it will last without loss of functional qualities. An important parameter is the environmental friendliness of the material. For the fire safety of housing, its resistance to fire is of great importance.

Such insulation as mineral wool is produced from molten rocks. It perfectly retains heat, is resistant to temperature changes and aggressive environments, does not rot, and weakly absorbs moisture. Mats of this material can have different thicknesses, so they are convenient to use when arranging the thermal insulation of a mansard roof.

Molten glass is used to make glass wool. According to its characteristics, this type of insulation has much in common with mineral wool, but it has a thermal threshold below -450 ° C. It is a good sound and heat insulator. But moisture can collect between its fibers, so installation work should be done correctly.

Glass wool and mineral wool are inexpensive, and insulation with their use will cost minimal financial costs. But their use requires laying a thick layer of thermal insulation and a reliable device for hydro- and vapor barrier.

To insulate the roof structure from the inside, polymeric materials are also used. For example, the advantages of polyurethane foam are a high degree of heat retention, durability, low weight. It does not pass steam and is resistant to moisture. See also: "How to insulate a mansard roof - the choice of materials and the rules of insulation."

Expanded polystyrene can very effectively insulate the attic without removing the roof. Its thermal conductivity coefficient is 0.05 W/m²K. It is a hydrophobic material that does not allow steam to pass through. Expanded polystyrene can have a flammability class G1 - G4. By the way, polymeric heaters are expensive artificial materials. Therefore, they are not used when they want to build a house only from environmentally friendly products.

It should be noted that natural heaters have good thermal conductivity, but they also have disadvantages. For example, foamed glass is very brittle, and materials such as mats made from straw and reeds, granulated paper, are highly flammable. It is necessary to know how a mansard roof is insulated with natural heat insulators, and to possess the appropriate skills.

Thermal insulation technology

For high-quality installation of insulation when installing a roofing pie, you need to study the step-by-step instructions for performing construction work.

The process of insulating a roof on a house consists of a series of steps:

preparation for laying insulation;
installation of thermal insulation;
fastening material.

The phased arrangement of insulation is as follows:

During the development of the project for the construction of the truss structure, it is necessary to determine the installation step of the rafters. At the same time, one should not forget that it should turn out to be strong and reliable, and the gap between the rafter legs cannot exceed the standard values. In the case when the heat-insulating material has already been selected, the rafters are mounted so that the insulation boards fit tightly between them. This technology greatly simplifies installation and minimizes the amount of waste building materials.
A layer of waterproofing is mounted between the rafters and the crate above the thermal insulation. Her canvases are overlapped, starting work from the bottom edge of the slope. Each subsequent row should overlap the previous layer by 15 centimeters. The film is fixed on the tree with a construction stapler. Then counter rails are attached, the thickness of which provides a ventilation gap of sufficient size. The slats are fixed on the rafters with self-tapping screws, although nails can also be used.
From the inside of a fully prepared truss structure, the insulation is laid and securely fixed.

The nuances of warming a sloping roof

Rafter legs, which are made of wood or metal, are cold bridges, since their thermal conductivity is worse than that of the heat-insulating materials used. Given this circumstance, when arranging the attic, it is necessary to install a heater not only between the rafters. It is necessary to place a continuous layer of thermal insulation on top of the laid mats, but in this case a thinner material is used.

The above technology improves the quality of insulation. But this method has disadvantages, these include the fact that as a result the rafters are completely closed and it will be difficult to use them to fix other elements of the roof structure. To ensure further installation work, it is necessary to note the location of the rafters.

A vapor-permeable film is laid on top of the thermal insulation layer, which performs the function of removing excess moisture. Next, the crate is attached. At the final stage of thermal insulation work, the inner lining of the ceiling surface is produced.

The precise implementation of the instructions on how to insulate the sloping roof of the attic allows you to use the living space throughout the year, since a favorable microclimate will be created in it.

Self-insulation of the mansard roof is quite feasible, but for this it is necessary to fulfill the requirements for this type of roofing work.

Mansard roof insulation: how to insulate, thermal insulation device, attic insulation technology with a sloping roof

Mansard roof insulation

If the attic remains non-residential, the air in the under-roof space serves as good thermal insulation (along with floor insulation). In the case of the attic, everything is completely different: here the thermal insulation is very close to the roofing material and the task is not only to insulate the attic, but also to create conditions so that the entire roofing system serves for a long time.

Insulation of a sloping mansard-type roof must be carried out according to certain rules

Let's say right away that all the wood that is used in the construction of the roof must be treated with antiseptics. Indeed, everything: both battens and counter-battens, and rafters. All wooden parts. It is also necessary to make them less flammable. To do this, they are treated with flame retardants. All elements that are located on the side of the street are treated with compounds for outdoor work. Treat all wooden parts facing the inside of the room with impregnations for interior work. If you use the composition for outdoor use indoors, the specific smell will remain for several years. If the opposite is true, the wood on the outside may suffer: the degree of protection is insufficient. So don't skimp on this.

More. Before describing how to insulate a mansard roof with your own hands, it is worth recalling this: a ventilation system must be organized in the under-roof space. For this, special ventilation holes are arranged on the skate. Through them, the air from under the roofing material escapes, carrying away excess moisture. And it must fall under the roofing through the overhangs. There absolutely can not be done all hermetically. That's where the air comes from. Only in this way will the condensate dry out in a timely manner and the roof will serve for a long time.

In order for the insulation to be correct and moisture to be removed in a timely manner, it is necessary to move air masses under the roofing material

Proper attic insulation

In order for the attic floor to be warm in winter and cool in summer, there are no problems with high humidity, icicles do not freeze on the roof, it is necessary to properly insulate the roof. But in the case of a roof, insulation, vapor and waterproofing are a complex solution, and one without the other works very poorly, or does not work at all.

If the sloping roof is at the same time the walls of the attic floor, the pie will be as follows (from inside to outside):

internal lining (drywall or lining);
crate;
vapor barrier;
insulation (the thickness of the insulation depends on the region and the parameters of the insulation, for central Russia it is about 200 mm);
superdiffusion membrane;
ventilation gap;
crate;
roofing.

How to insulate a mansard roof: a sequence of layers of a sloping roof for a living space

The photo shows the insulation of a broken mansard roof in a graphical version. Please note: a superdiffusion membrane is laid over the insulation (indicated in blue). Its purpose is to prevent condensate formed or precipitation seeping through the roofing from entering the insulation and removing the steam that nevertheless got into the mineral wool, ensuring its drying. Therefore, with a vapor permeability of 1500 g / m 2. This layer is often called waterproofing (as it is, in fact, it is), only waterproofing is vapor-permeable.

Laying waterproofing

Ideally, it fits exactly as shown in the figure: wrapping the rafters and closely fitting on the insulation. Often, to save money, they roll it out over the rafters, but without pulling it, but making it sag by 3-5 cm. This option also works well: moisture gets to the surface, and then rolls down and out of the roof. Here is another important point: the membrane must go into the gutter. Then the moisture will be removed from the under-roof space.

You can also lay waterproofing like this: with a slight sag, but definitely NOT pulling it

A few more points on laying the membrane. It rolls across the rafters, starting from the bottom. The first row is launched into the gutter. The next one is rolled out with an overlap of 10-15 cm. And so on until the ridge. On the ridge, the membranes are cut off on both sides along the upper edge and fixed. A strip rolls along the ridge, descending from one and the other side of the roof. It turns out a coating through which water flows down to the gutter itself.

Vapor barrier and rules for its installation

It is worth talking separately about the vapor barrier. It must also be a membrane. Polyethylene or polypropylene film will not work: its characteristics are not the same. The vapor permeability of this layer (expressed in g/m2) should be as low as possible. Ideally, it is equal to zero. That is, this layer should not allow vapors to pass from the room into the insulation layer. When using mineral wool as insulation, this is very important: when wet, it loses more than half of its properties, and when it freezes in a wet state and then melts, it generally crumbles into dust.

Therefore, the vapor barrier film is also laid with the entry of one panel onto another. Moreover, these joints are glued with a special double-sided vapor-tight tape (it looks like sticky rubber). Ordinary painting or stationery will not work. They do not provide 100% vapor protection. In addition to the joints, all junctions are also glued: from below, from the sides, from above.

A line is drawn on the vapor barrier. It marks the border from which the next layer starts (this is the amount of overlap) and the line along which the canvases are fastened with adhesive tape

The vapor barrier is usually attached to the lags with stapler brackets or, as in the figure, with planks of the inner crate for mounting the skin. In this case, another ventilation gap is formed, which will dry the finish and the membrane. This clearance is desirable but not required. In principle, the lining can be mounted directly on top of the membrane.

thermal insulation

The better to insulate a sloping roof - the question is complex and there is no unambiguous answer to it. Mineral wool is used, only hard, with a density of 30-50 kg / m 3. Since the mansard roof usually has a large angle of inclination, soft materials can slip. It is for this reason that it is better to take plates. Although in this case it will be necessary to adjust the pitch of the rafters to the dimensions of the insulation: it should be 10-15 mm less than the width of the plate so that the material becomes “spread” between the beams and holds well.

It is necessary to lay thermal insulation in such a way that there are as few cold bridges as possible. For central Russia, usually 200-250 mm of mineral wool is required. These are several layers of mats. When laying between the rafters, the slabs are positioned so that the seams of one row overlap the next. The width of the insulation, as already mentioned, should be slightly wider than the distance between the rafters. Then the plate becomes dense, excluding the presence of cracks. If the width is more/less, you have to cut the material. At the same time, the chance to get a smooth edge is small and there are many residues.

If the dimensions of the rafter do not allow laying the entire insulation, planks of the required thickness are stuffed across from the side of the room. Between them lay the remnants of insulation. From above, a vapor barrier is already attached to it and, if necessary, a crate for finishing. This option is even better: cold bridges are completely excluded, blocking even the rafters. This method requires a little more installation costs, but it will definitely be warmer in the attic, which will reduce heating costs.

How to insulate a mansard roof: the order of work

The device of the attic floor is good because it allows you to stretch the end of construction. It is immediately necessary to lay and fix the superdiffusion membrane on the rafters, the crate and roofing material on it. And attic insulation can be done from the inside after a while.

But pay attention: the waterproofing layer must be mounted together with the roofing. This is the main mistake of many developers: they do not lay this membrane. As a result, either it is necessary to remove the roof and lay it, or to invent systems to correct this shortcoming. The whole problem is that in this case there is no cheap solution that guarantees the normal state of the materials.

We warm outside

If you do everything at once, the order of work is as follows:

from the side of the room, a crate is stuffed across the rafters - thermal insulation will lie on it, instead of a crate, a cord or galvanized wire is sometimes attached;
heat-insulating material is laid on it from the side of the roof (according to all the rules, shifting the seams, making sure that there are no gaps);
a superdiffusion membrane is rolled over the thermal insulation;
crate is stuffed;
roofing is laid;
from the side of the room, a vapor barrier is fixed and glued;
with or without crate mount trim.

Insulation of the mansard roof from the outside: it is not difficult to work, the thermal insulation is laid on the crate lined from below

With this option, it is not difficult to work with a heater: it is easy to lay it, it relies on a crate (laces).

Warming from the inside

This option allows you to move the interior decoration for the required period (useful if there is a shortage of funds). After installing the truss system, here's what you need to do:

roll out and fix the waterproofing;
stuff the crate (if necessary, a counter-crate);
install roofing material.

For the first stage, this is all the necessary work. After the opportunity to continue, you will need to insulate the mansard roof from the inside. It will no longer be so convenient to work: you will have to make a building envelope that will not allow you to push the insulation higher than necessary. The cotton wool itself will have to be fixed in some way: it strives to fall on the head. The order of work is as follows:

between the lags in increments of 40-50 cm, stuff the strips that will hold the thermal insulation, providing the required ventilation gap;
thermal insulation of the required thickness is laid and fixed (the rules remain the same);
a crate is nailed to hold the layers of insulation;
a vapor barrier membrane is laid and glued;
the crate and finishing material is mounted.

If you use plates, then it is also easy to insulate the attic from the inside.

A few notes on how you can lay the heat-insulating material. If these are high-density mineral wool mats and their width is a little more than the step between the joists, everything is relatively simple: they themselves hold up well.

If rolled mineral wool is laid, everything is more complicated. Making the insulation of the mansard roof from the inside, it is laid from the bottom up. Take a string, a construction stapler. Roll out the cotton wool, press it against the planks, fasten a piece of lace with staples, drawing the letter Z. This is how you fix the first layer, followed by the second and all subsequent ones.

In general, if you want the mansard roof to be warm, it is better to use mineral wool mats of the required density of 30-50 kg / m 3. They are tough enough to hold their shape well. Softer rolled materials on vertical surfaces or with a large slope are caked, settling down, the thermal insulation of the mansard roof deteriorates.

These are the consequences of laying mineral wool rolls of insufficient density

What is the best way to insulate a mansard roof

As mentioned above, the most popular material for insulating a mansard roof is mineral wool. It is good, but not at all ideal: it is afraid of moisture. That is why it requires such careful protection from all sides so that it retains its properties.

Styrofoam (expanded polystyrene)

Sheathe the roof with polystyrene foam or extruded polystyrene foam - EPS. Polyfoam (grades PSB-S-25, PSB-S-35) has good characteristics, but when burned, it emits harmful substances, although there are self-extinguishing grades (with special additives). Here they are better for roof insulation for roof insulation.

The main advantage of polyfoam: low price. It is mounted simply: it is placed between the rafters, all joints are sealed with mounting foam. It is convenient to insulate the attic from the inside with foam plastic: order the plates of the right size - 10-15 mm more than the gap between the rafters - and put them tightly. Due to the elasticity, they hold very well.

From the side of the roof, a ventilation gap is also left and waterproofing is laid. But it protects more a wooden structure, since polystyrene foam is not afraid of moisture, it practically does not absorb it itself, it does not conduct steam. This is where the main drawback lies. Since the material does not let the vapor through, a good ventilation system is needed in the attic, and this is an additional cost.

XPS has the best characteristics: under equal conditions, its thickness is two times less than mineral wool of the specified density and one and a half times less than that of polystyrene. It also has a system of locks, which reduces the risk of cracks, through which heat will fly away. Another plus: mice and insects do not like extruded polystyrene foam, fungi and mold do not multiply on it. What limits its use: a solid price. You also need a ventilation system.

EPPS brands - Ekstrol, STEREKS, PENOPLEX, URSA XPS, Technoplex, PRIMAPLEX (PRIMAPLEX), Styrofoam (Stirofoam), KINPLAST (KINPLAST), Teploizolit, GREENPLEX (GREENPLEX). While the technology is the same, there are some differences in performance, so compare when choosing.

Not so long ago, a new type of insulation appeared: expanded polystyrene foam. It is applied in liquid form to the surface, reacting with air, increases in size many times, filling all the cracks and forming a monolithic layer. This is perhaps the only way today to correct the situation and insulate the attic with high quality, if during the installation of the roofing they forgot to lay a layer of waterproofing.

This is the process of insulation with expanded polystyrene foam (left) and what happened as a result. Excess is trimmed to the level of the lag

This insulation has good characteristics (thermal conductivity coefficient 0.036-0.040 W / m² ° C), but a special application technology. It is necessary to organize a closed cavity into which the composition is poured. In the case of a mansard roof, the side parts are rafters, sheet material (fiberboard, GVL, plywood, etc.) is nailed to them from below and from above.

A feeding sleeve is launched into the formed cavity, from which loosened cotton wool comes out under pressure. It fills all the cavities, forming a single layer of insulation.

The process of insulating a mansard roof with ecowool

The main advantage of ecowool compared to all the heaters described above is that it conducts steam. It can absorb moisture up to 20% of the volume, and then give it away. That is, there is no need to organize a vapor barrier: humidity is regulated in a natural way, as is the case with wood. The ventilation gap between the roof and the insulation should be all the same, as well as the properly organized movement of air masses in it.

this information is the most understandable and compact. I want to insulate the roof, which partially captures the second floor. Approximately 1.7 m along the upper vaults of the 2nd floor. ventilation gap. In winter there was condensation, mold has gone in places. I will do the insulation according to your recommendations. The question arises with the attic. Leave it uninsulated or insulate it together with the vaults of the 2nd floor. they advised to install 6 aerators in the ridge. The attic area is about 80 m². I want to ask if this will help? Or leave the attic cold and deaf? In other words, the air through the ventilation gaps will rise to the attic and go into the cracks on the ridge. it is covered with clapboard. I think to drill holes around the perimeter around the entire eaves for air flow. Your opinion, if it doesn’t make it difficult. Thank you

If you do not plan to use the attic as a living space, it is quite possible to leave it cold. Then it will be easier to make ventilation. Everything turns out exactly as you planned - aerators will provide natural ventilation of the attic space. At the same time, exhaust ventilation ducts can not be taken out to the roof, but stopped in the attic. From here, through the aerators, the polluted air will leave itself. In this case, the problem of overgrowing the channels with ice disappears.

Attic insulation: inside, outside, materials

It is always tempting to use an attic space for living. For comfortable conditions, it is necessary to insulate the attic room. It can be done inside and out, using different materials.

Mansard roof insulation instructions

The dimensions of the attic, as a rule, are limited by roof structures. And often the attic is not protected by load-bearing walls with digestible thermal insulation. Therefore, the insulation of the mansard roof must be carried out especially carefully.

Mansard roof in the process of insulation

Do-it-yourself insulation of the attic roof

Self-insulation of the attic roof is quite feasible. However, it is necessary to remember the requirements for the design of such a roof:

mansard roofing involves the use of lightweight materials to reduce the load on the truss system. For example, natural tiles are inappropriate for her;
for insulation and insulation of the mansard roof, you should also choose effective lightweight materials, which will reduce the weight of the structure;
Ventilation plays an important role in the attic roofing system. Any puncture in the development or installation will lead to an increase in the level of humidity in the living room, a decrease in the properties of the insulation and damage to the elements of the supporting structure.

Mansard roof insulation technology

Roof insulation of this type can be carried out in two ways: from the inside and outside. Each of the methods has its advantages and disadvantages, however, external thermal insulation is considered the preferred method due to higher results.

Mansard roof insulation from the outside

Private house with an attic floor in the process of insulation from the outside

Installation of thermal insulation for a mansard roof is quite simple and comes down to preparing the working space, laying and fixing materials:

We hem the lower part of the rafters with plywood, OSB or edged board.
We lay a vapor barrier layer on top. Its canvases and joints with the structure must be glued with foil tape. When installing this layer, it is important not to confuse the side of the material: the vapor barrier functions in one direction.
The next layer is insulation. When laying it, it is important not to leave voids.
Next, we spread a hydrobarrier over the rafters. We also glue the strips of material with special tape.
Then you need to make a ventilation gap. To do this, a rail with a height depending on the type of roofing is mounted on the hydrobarrier along the rafters. A wavy roof involves a rail of 20-30 mm, a flat one - 50 mm.
At the last stage, the crate and roofing are installed.

Mansard roof insulation from the inside

The photo shows a mansard roof in the process of insulation from the inside

The internal insulation of the attic roof, although it seems to be a more rational method (given the protection of the room from precipitation), still has a number of disadvantages:

most heaters are simply inconvenient to mount from the bottom up, and laying out and fixing rolled materials is almost impossible;
often the truss system is reinforced with various connections and girders, at the junction points of which voids remain unprotected by thermal insulation. This forms cold bridges, respectively, the insulation of the mansard roof does not work well.

The internal thermal insulation of the mansard roof is as follows:

Starting from the lower edge of the roof, we lay out the waterproofing film with an overlap, fasten the edges with adhesive tape. At the walls, this coating should have a small margin, and the excess is removed after the installation work is completed.
To ensure the ventilation gap, as well as a high-quality fit of the film to the roofing material, we nail counter-battens to the rafters with nails.
Then we lay out the insulation tightly, without gaps, for example, mineral wool.
Further, the entire space is sewn up with a vapor barrier membrane. It is fixed with overlapping construction brackets.

Insulation of the mansard roof with foam

One of the options for insulating a mansard roof using foam

Styrofoam (or expanded polystyrene) is one of the most popular heaters, which is used for thermal insulation of foundations, facades and mansard roofs. If you don’t know how to best insulate your mansard roof with foam, read our instructions, which describe all the steps step by step.

This material has an impressive number of advantages:

low cost;
sufficiently high resistance to stretching and compression;
light weight;
wear resistance (resistance to mechanical stress and temperature extremes);
high rates of moisture and fire resistance;
easy installation;
service life from 25 to 80 years.

Insulation of the attic roof with foam plastic is done as follows:

We remove protruding screws and nails from the wooden elements of the roof structure;
We lay a waterproofing film on the rafters, fasten it with a furniture stapler. If we are talking about a finished building, the film is not laid on the rafters, but through additional slats.
Then, foam sheets are laid out between the rafters, each of which is adjusted with a knife to fit tightly and eliminate gaps. You can fix the insulation with wooden slats, glue or special dowels with wide caps.

Mansard roof insulation scheme using Yutafol vapor barrier as an example

Insulation of a broken mansard roof

Due to its characteristics, a broken mansard roof must be properly insulated:

The vapor barrier is mounted from the inside of the attic room with a solid carpet. Joints are sealed with special adhesive tape;

On the video you can see the process of warming the attic with a broken type of roof

Mansard roof insulation materials

The choice of material for the thermal insulation of the mansard roof depends primarily on the climatic conditions of your region. Given the thermal properties, each insulation has its own necessary heat-insulating layer.

One of the best options for insulating the attic from the inside is polyurethane foam. The photo shows the installation process of this material.

Consider heaters by popularity:

The most common and high-quality mansard roof insulation is basalt wool. Its installation is carried out in two layers, with overlapping joints. Most regions require laying a layer of 150-200 mm;
the next most popular is polystyrene foam. Its required thickness is determined by the characteristics of the brand of the product;
modified mounting foam - polyurethane foam. This material allows you to solve the problem of roof insulation from the inside. It can be applied in smaller layers due to its thermal properties. It also has a high level of adhesion and fills the voids of the structure well;
contrary to popular belief, Ursu is not recommended for use as a mansard roof insulation. The layer of this material necessary for thermal insulation is almost impossible to fix. In addition, after a while it can “roll” down the structure if the mounting surface is inclined.

From this video you will learn how to insulate a mansard roof with your own hands using available materials. The necessary diagrams and sketches are also included.

Do-it-yourself insulation of a mansard roof is a fairly easy process that does not require high professional training and expensive materials. Basic knowledge in the field of construction and skillful hands will allow you to insulate and decorate any mansard roof with high quality and for a long time.

Mansard roof insulation technology - tips on how to properly insulate from the inside with your own hands, materials and diagram, video

Information article about the insulation of the mansard roof: technology, materials, thermal insulation of a sloping roof, foam insulation. September 7, 2016
Specialization: Capital construction works (laying the foundation, erecting walls, constructing the roof, etc.). Internal construction works (laying of internal communications, rough and fine finishing). Hobbies: mobile communication, high technologies, computer equipment, programming.

Some time ago, I completed an order for attic insulation for winter living. While doing the work, I thought that the technology I used is quite simple and even an unprepared person can make thermal insulation with their own hands from the inside.

In today's material I will tell you what is better and how to properly insulate the attic from the inside with your own hands. This guide will help you avoid the same mistakes that I had to make in the beginning of my career as a builder.

I assure you that at the end of the work, the attic floor of a wooden house will turn from an unnecessary storage of trash into a cozy and comfortable room, for living in which all your household members will fight.

Features and methods of insulation of the attic room

Before talking about ways to insulate the under-roof space from the inside, I want to note that this is a must, even if you are not going to live in a house in the winter. The fact is that the attic, due to its location, is very warm by the sun in the summer, so without a reliable insulating layer, the temperature inside will be uncomfortable (or you will have to install a very powerful air conditioner).

If you have already insulated ordinary living quarters and think that you know how to insulate the attic, I have to disappoint you. The thermal insulation of a room under the roof (not an ordinary room on the second floor, namely the attic) has some features that I simply have to mention:

The geometry of the attic room follows the contours of a pitched roof, therefore it is far from a standard cube or parallelepiped. Insulation will have to be installed on inclined surfaces, so the choice of heat-insulating material will have to be approached with great care. For example, the use of too soft and flexible products is completely excluded.
The roof truss system and roofing are always made of lightweight materials so as not to exert a large load on the load-bearing walls of the house. Consequently, the heat-insulating cake should weigh as much as to only slightly weight the structure, otherwise the roof may collapse with a significant snow load.
In addition to the roof slopes, the attic has two more gables and a floor (it is also an attic floor). If you do not perform thermal insulation of these surfaces, all efforts to install insulation in the rafters will not lead to any significant result.

The roofing material, no matter how reliable it may be, can pass atmospheric moisture, which, in turn, can damage the insulation layer or significantly reduce its technical characteristics. Therefore, during installation, it is necessary to reliably protect the thermal insulation from moisture.
When buildings catch fire, the fire usually moves to the upper part of the dwelling, where the attic is located. Therefore, to ensure the possibility of evacuating people from this room for thermal insulation, I personally recommend using non-combustible or poorly flammable heaters. After all, the matter is further aggravated by the fact that the roof truss system is made of wood, which cannot be classified as NG.
And last but not least, environmental friendliness. Care must be taken to ensure that the insulation does not pose a danger to people living in the attic, regardless of the conditions of its operation - heating, moistening, freezing, and so on.

First, let's decide on the method of thermal insulation. There are two options:

Insulation of attic walls. This method is resorted to in the case when the roof slopes are not the walls of the attic. The role of the latter is played by additional partitions made of wood, drywall, plywood, and so on, which should be insulated.
The advantage of this method is the presence of additional ventilated space under the roof. Minus - a decrease in the useful area of \u200b\u200bthe room.

Insulation of roof slopes. In this case, the heat insulator is installed in the truss system, after which it is possible to divide the spacious attic with the help of thin partitions, without worrying about cold or heat. The advantage is that the entire under-roof space will be insulated. And with the help of partitions, you can divide it into several separate rooms, arranging an additional pantry in the attic room.

I prefer the second method of insulation, so it will be discussed further.

Choice of materials and tools

It's time to decide how to insulate the attic room from the inside. To do this, you can use expanded polystyrene, expanded clay, polyurethane foam, ecowool and many other heat insulators that domestic and foreign industries offer to purchase.

But I am insulating the attic with basalt wool. This material, in my opinion, best meets the requirements for the heat-insulating layer of such a room.

I will briefly list the most important advantages of basalt mats:

Characteristic	Description
Low thermal conductivity	The material retains heat indoors so well that for effective thermal insulation it is enough to install a layer 10 cm thick.
Hygroscopicity	Basalt fibers do not absorb water and have hydrophobic properties, so moisture that has got inside is quickly removed through the gaps without reducing the operational properties of the material.
Vapor permeability	The material does not prevent air infiltration, normalizing the humidity in the attic and extending the life of wooden parts.
Incombustibility	Basalt wool does not ignite in a fire and contributes to the extinction of the flame, giving time for the evacuation of people or the elimination of the source of ignition.

I could talk about the advantages of mineral wool for a long time, but this is not the topic of today's article. Therefore, he simply noted the better it is to insulate the attic from the inside.

I prefer to use TechnoNIKOL Technolight Extra basalt mats 10 cm thick, 120 by 60 cm in size. It is not advisable to buy a denser material, since it will not experience load between the rafters.

It is very important to pay attention to the dimensions of the material. I chose TechnoNikol mats because their width is 60 cm, namely, this is the distance between adjacent rafters in the case I am describing.

In addition to direct thermal insulation, other materials are also needed:

Wooden bars with a section of 30 by 50 mm, with the help of which a counter-lattice will be formed for ventilation gaps that help remove moisture.
Super diffuse vapor permeable hydro- and windproof membrane. These films are of especially high quality from Strotex and Juta, so I recommend buying them.
Penofol. A thermal reflective material that I'm going to use in place of the standard vapor barrier film that keeps the mineral wool from getting wet from inside the room.

Antiseptic primer. She needs to process the roof trusses to prevent the appearance of mold and fungus. You can buy a composition with fire retardants, thereby increasing the fire safety of the building.
OSB boards. They will be needed to construct the crate, on which flexible tiles are laid on one side and eurolining on the other. If you are going to use other materials, then a solid crate may not be needed.
Polyurethane mounting foam. Useful for sealing joints between mineral mats.
U-shaped perforated brackets for mounting galvanized lathing. For me, they will hold the installed mineral mats in place until they are sewn with decorative material.

Well, now you can safely move on to how to insulate the attic from the inside with your own hands.

Arrangement of insulation

The whole process of warming can be conditionally divided into several steps:

So, I will explain how to do the work correctly with my own hands in each of the mentioned stages.

Step 1 - Laying waterproofing and roofing material

Let's start with the installation of the waterproofing membrane, since it is installed outside the room before fixing the roofing. Only in this way can the insulating layer be reliably protected from the ingress of atmospheric moisture into it.

I must say right away that the entire roof truss system in the case I am describing was installed. However, the roofing material and the crate on it have not yet been laid.

The process consists of the following steps:

I roll out the first layer of hydro- and windproof membrane. You need to start work from the bottom of the roof slope, gradually moving up. The membrane is fixed with staples and a construction stapler or wide-head nails. It is necessary to install the film not tight, but with a slight sag (about 2 cm per meter), so that when the air temperature decreases, it does not tear.

I lay the second and subsequent sheets of waterproofing film. You need to act in the same way as in the previous paragraph. But there is one point here. The edge of the upper membrane must overlap the edge of the lower one by 10 cm to ensure complete impermeability to moisture.

I seal the seams of the membrane. For this, adhesive tape is used. It just needs to be glued to the joints of adjacent waterproofing membranes.
I install a control panel. Its role is played by wooden bars, which are fixed with self-tapping screws over the waterproofing membrane on the rafter supports. Previously, I recommend impregnating them with an antiseptic and flame retardant in order to extend the life of the roof structure.
I fix the boards of the additional crate. They are installed perpendicular to the rafters and fastened with self-tapping screws to the counter-bar. The step between adjacent parts is about 40 cm.

I install OSB base plates. They are attached to the boards with self-tapping screws. Here it is necessary to monitor the length of the fastening fittings so that too long screws do not tear the hydro- and windproof membrane located below.

Installing a flexible roof To do this, a lining carpet is glued to the slabs, after which shingles of flexible tiles are fixed on it.

If you are insulating the attic with a finished roof, then the waterproofing membrane will have to be installed from the inside. This method has two disadvantages:

the labor intensity of the work being carried out increases;
waterproofing film will not protect the wooden roof trusses.

It is necessary to fix and seal the film so that it wraps around the rafters and adheres to the roofing sheathing. Thus, peculiar baths are formed, in which insulating material will be invested.

But before that, it is necessary to prepare the under-roof space for the installation of mineral mats.

Step 2 - Preparing the truss system

The space under the roof, namely the truss system, is being prepared for thermal insulation:

I clean wooden parts from dust and debris, remove objects that interfere with the installation of mineral mats. It is best to clean the rafters with a vacuum cleaner, which will remove dust, sawdust and shavings left after the installation of the roofing material. You should also check if the sharp ends of screws, nails, and so on do not stick out from somewhere. They can cause injury or damage insulation materials.

I install engineering communications and insulate them. Ventilation and chimney pipes can be installed on the roof, as well as the electrical wiring necessary to connect household appliances in the attic room:
- Ventilation pipes, if they are laid in the non-insulated part of the attic, must be thermally insulated with mineral wool or foam shells.
- For a chimney, a box should be designed to pass through the attic floor and roof. They must be filled with heat-insulating material (most often perlite or expanded clay), which will increase the fire safety of the room.
- Electrical wiring should be placed in polymer flexible or rigid cable ducts that will prevent the rafters and insulation layer from igniting in the event of a short circuit.

I prime wooden surfaces. For work, it is better to use a universal composition that has both antiseptic and fire-fighting properties. For example, the composition for wood BS-13 or Fire protection Strazh-2. It must be applied to wooden parts with a roller or sprayer, after processing in two layers with intermediate drying for 3 or 4 hours.

I install U-shaped brackets on the side surfaces of the rafters. It is not necessary to use them, since with the correct installation of the rafters, the mineral mats become tight by surprise. But I'm used to playing it safe, and their acquisition does not hit hard on the budget planned for insulation. But if you use cotton wool in rolls, you can’t do without it.

Step 3 - Installation of thermal insulation

Insulation of the attic from the inside continues. Let's move on to the main part:

I do cutting mats. Mineral wool is cut into the required pieces with a sharp knife or saw with very fine teeth. If the distance between the rafters corresponds to the width of the insulation, there is practically no need to trim.

I install mats between the rafters. To do this, you need to slightly bend the material in the middle, and then insert the insulation in the right place. Having straightened, the basalt mat will take its place and will not fall out of the inclined surface.

I fix the mats with brackets. You just need to bend part of the bracket so that its edge is on the surface of the mat and holds it in place. Instead of brackets, you can use galvanized perforated tapes that are attached directly to the lower edges of the rafters.
I seal the seams of the material with polyurethane mounting foam. Gaps must be filled with a gun. Moreover, act in such a way that the composition is inside the entire gap, and not just on its surface. If you make a mistake at this stage, cold bridges may form at the joints, which will reduce the effectiveness of insulation.

To increase the reliability of the heat-insulating layer, you can install not one, but two layers of insulation. Just take mineral mats with a thickness of not 10, but 5 cm. Then the individual layers are installed so that the joints are apart. And cold bridges can not be feared at all, although it is still worth sealing the seams.

Step 4 - Finishing coat

Decorative finishing of the enclosing structures of the attic room is carried out as follows:

I install a heat-reflecting and vapor barrier layer. As you understand, penofol will serve me for this - foamed polyethylene with a reflective layer of polished aluminum foil. It is mounted as follows:
- The first sheet of penofol is installed with a foil layer towards the living quarters, after which it is aimed at the rafters using a construction stapler.
- The second and subsequent sheets of material are installed so that between the individual elements there is an overlap of 10 cm.
- The joints of the penofol are glued with double-sided adhesive tape (inside the joint) or metallized tape (which is glued on top of the joint). It is necessary to make sure that a completely homogeneous and sealed layer is formed.
- If the thickness of your rafters is such that the edge of the insulation does not reach the cut of the tree, then penofol must be laid on the surface of mineral wool, fixing it on the side surface of the roof support beams. Otherwise, it may rustle when air passes through the ventilation gap.

I mount the bars of the control battens for arranging the ventilation gap. It is necessary to fasten the planks with self-tapping screws to the rafters on top of the foam. These details create a gap between the finish and the heat-reflecting surface, which is necessary to remove condensed moisture.

Installing OSB boards. They are attached to the counter-lattice with self-tapping screws. Everything is standard here, with the exception of some small nuances:
- It is necessary to install the sheets so that at the edges (at the gables and the floor) there is a gap of 1-2 cm thick. It is necessary to remove excess moisture and compensate for possible changes in the size of the material.
- The seams between adjacent slabs should be staggered (staggered) and be 2-3 mm thick to avoid warping of the surface during thermal expansion of the base.
- It is necessary to fix the plates so that their edges are located on the bars of the counter-lattice. The distance between the screws is no more than 20 cm.

You can later install eurolining or other decorative material on the plates. And we have ahead of the insulation of the gables, which form two of the four walls of the attic room.

Step 5 - Warming the gables

I strongly advise these parts of the attic to be insulated from the outside, using dense mineral wool for this, which can be covered with cement plaster on top. The scheme of work is as follows:

Preparing the surface for work. To do this, you need to clean the surface of the walls from the remnants of mortar, debris, dirt and dust. After that, the following operations are performed:
- Damage repair. If gaps and cracks are found in the masonry, they must be sealed with cement mortar or blown out with mounting foam.
- Surface priming. To do this, you need to take a primer for a brick or (not the one with which you processed the rafters), and then cover the pediments with it in two layers with intermediate drying.

I mount the start profile. This is a perforated galvanized part on which the insulation layer will rest. It is fixed at the bottom of the wall strictly horizontally. If several of these parts are needed, then install them with a small gap to compensate for the thermal expansion of the metal.

I glue the first row of mineral mats. Let me remind you that you need to use dense mineral wool, which is intended for subsequent finishing with cement mortar. The sequence of actions is as follows:
- The surface of mineral wool is pre-reinforced with cement glue, which is evenly distributed over the slab with a spatula.

A bead of cement glue is applied to the mineral wool at a distance of 5 cm from the edge. Several lumps of glue are also placed in the middle of the mat so that at least 40% of the sheet surface is covered.
The part is attached to the wall. at the same time, its lower end must be supported on a pre-installed starting profile. Using a water level, it is necessary to check that the basalt mat is installed strictly vertically in all planes.
Behind the first layer, other mats are glued to the wall in the same way. It is necessary to follow the verticals, and that the seams between adjacent parts are minimal.

I glue the second and subsequent rows of mineral mats. There are no differences compared to the procedure described in the previous paragraph. You just need to make sure that the vertical ones go sideways. That is, the seam of the upper row fell in the middle of the insulation sheet of the lower row (as in brickwork).
After the solution hardens, I fix the insulating layer with dowels - “fungi”. They are installed as follows:
- A hole is drilled directly through the mineral mats in the wall using a perforator, the depth of which in brick or concrete should exceed 2 cm.
- A dowel is inserted into the resulting hole, after which the core is installed inside.
- Using a hammer, the core is hammered into the dowel so that its cap is slightly recessed into the surface of the insulation.
- It is not only mineral mats that need to be fixed. "Fungi" should be installed in the seams of the insulating material so that the heat-insulating layer does not come off under load.

I seal the seams of the material. To insulate the joints, polyurethane foam is used, which glues the fibers of the insulation together, preventing the formation of cold bridges at the junctions of adjacent mineral plates. It is necessary to fill the seam with a gun as tightly as possible.
I reinforce the surface of the insulation with an alkali-resistant fiberglass mesh. To do this, mineral mats are covered with a reinforcing compound, after which a mesh is placed on it and pressed into the mortar with a plaster trowel. Then a little more solution is applied on top so as to completely hide the mesh inside.
I do surface finishing. The reinforced insulated surface of the gables is plastered, after which it is decorated with the selected decorative material. In the simplest case, you can simply paint the gable with facade paint.

That's all. Some still resort to thermal insulation of the interfloor ceiling, however, with such powerful insulation that I have described, I consider this procedure unnecessary.

Summary

Now you know how to independently perform the correct insulation of the walls in the attic floor and the floor with your own hands using mineral wool at the lowest cost. However, there are other options.

For example, sprayed polystyrene foam, with which it is easy to carry out thermal insulation of complex areas, including the Mauerlat in a heated attic. You can learn how to spray PPU yourself from the video in this article.

If you have any questions - ask them in the comments!

September 7, 2016

If you want to express gratitude, add a clarification or objection, ask the author something - add a comment or say thanks!

The conditions for comfortable living in the attic rooms directly depend on the correctly made heat-insulating layer. Insulation of the mansard roof will allow you to save precious heat in the winter, and in the summer heat it will create such a pleasant coolness in the rooms. But the creation of truly reliable and effective thermal insulation for the attic roof requires knowledge and understanding of insulation technology. In general, to perform the insulation of the attic roof with your own hands, you will need skills in handling the tool, desire and time.

Technology and scheme of mansard roof insulation

The technology of mansard roof insulation is in many ways similar to conventional roof insulation, with the only difference being that more stringent requirements are imposed on the attic roof. This is due to the design feature of the attic as a whole. It's all about the walls of the interior, which are literally drawn close to the roof, and in some designs they are one whole. That is why the attic rooms cool faster in winter, and warm up very much in the summer heat.

The very same scheme of insulation of the mansard roof is a multilayer cake, consisting of the following layers:

vapor barrier;
thermal insulation;
ventilation gap;
waterproofing;
roof.

Roof insulation scheme, video:

Each of these layers performs its task, and their presence is mandatory. But before insulating the mansard roof, the greatest attention should be paid to the heat-insulating layer and ventilation, since 80% of success in achieving comfortable living in the attic rooms depends on these two elements.

To answer the question of how best to insulate a mansard roof, you need to know why insulate it at all. So, the first thing thermal insulation is needed for is keeping warm during the cold period. The second is protection from excess heat during a hot period. For those who do not know yet, all thermal insulation materials have such an indicator as thermal conductivity, which is responsible for the transfer of heat from or to a room. The lower this index, the less heat penetrates through the layer of material and the smaller the thickness of the thermal insulation is necessary to obtain optimal insulation characteristics.

The importance of thermal conductivity cannot be underestimated. And that's why. We already know that the walls of the attic are integral with the roof. And in winter, in the heated attic room, most of the heat from the house goes towards the roof, and the unshakable laws of physics are to blame for this. Heat is transferred to the roofing material, covered with a layer of snow, which, by the way, is a natural insulation. Snow, due to its structure and internal air pockets, acts as an external insulation in the low temperature range from -2 °C. And now, when the warm roof and snow come into contact, the latter thaws a little, and since it is cold outside, it freezes again, forming an ice crust. But already ice does not have the thermal insulation properties of snow, in addition, it makes the roof heavier and destroys the roofing. If the thermal insulation of the roof, the roof in particular, is done correctly, then in winter the snow on the roof will lie evenly and not thaw.

As for the function of thermal insulation in the warm season, then everything is somewhat simpler. In the summer heat, excess heat from the roof is transferred inside the attic, and being in the room becomes simply unbearable due to the heat, and even several air conditioners cannot cope with this level of heat. A layer of thermal insulation will prevent this process, providing coolness under the roof. Of course, in comparison with the first floor, the temperature will be several degrees higher, but in the end it will be quite acceptable.

Now, knowing and understanding why roof thermal insulation is needed, you can turn your attention to the roof structure and its effect on high-quality thermal insulation. To make the attic thermal insulation correctly, it is necessary to compare the device of a conventional roof and an attic one. It immediately becomes apparent that the difference lies in the size of the ventilation space between the roof and living quarters. And if an ordinary roof has an attic with dormer windows for these purposes, then the ventilation space of a mansard roof is limited to 10 - 15 cm. For a properly made mansard roof, the presence of competent ventilation is no less important than the thermal conductivity of materials. There are several reasons for this. Firstly, ventilation removes excess moisture from under the roof, preserving and extending the life of the entire structure. Secondly, in winter, ventilation does not allow the roof to overheat, keeping the snow cover from melting and preventing the formation of ice. Thirdly, in hot summers, ventilation removes part of the heat from under the roof, preventing overheating of the interior and roof structural elements.

Material selection

Video: mansard roof insulation

Before starting work, it is necessary to determine the material of the insulation, since the number of layers of the heat-insulating cake and its thickness will depend on it. Today, the market can provide a huge selection of different thermal insulation materials. Popular are mineral wool, glass wool, Styrofoam, extruded polystyrene foam, foamed glass, polyurethane foam. In addition, do not forget about natural heaters - wood chips, paper, straw. But when choosing one or another material for attic roof insulation, it is necessary to focus on four main parameters. The first, already known to us, coefficient of thermal conductivity. For roof insulation, it is best to take material with a coefficient of 0.05 W / m * K and below. The second parameter is moisture resistance and the higher it is, the better. The third one is fire resistance. And the fourth - environmental safety of the material. There are no special questions with the last two parameters, since they do not indirectly affect the specifics of creating a heat-insulating cake. But the coefficient of thermal conductivity and moisture resistance can incline to the choice of a particular material.

Choosing as thermal insulation mineral wool or glass wool, it is necessary to be prepared for the fact that over time the insulating qualities of these materials will deteriorate greatly. This can happen for two reasons. The first is that the material was caked or, on the contrary, crumbled. The second - the level of moisture in the material exceeded all allowable standards. These problems are not surprising. Cotton wool, whatever it is, remains cotton wool, a material that is very susceptible to absorbing moisture. In addition, this material does not tolerate mechanical loads well and collapses under their influence. Another disadvantage of wool as an attic roof insulation is the need to create a thick cake of 3-4 layers of insulation to achieve the desired result. In conclusion, for thermal insulation from cotton wool, it is necessary to make several layers of vapor and waterproofing. But the price of cotton wool and its general availability make it very attractive.

It is also possible to insulate the mansard roof polystyrene. This material is not afraid of water and has excellent thermal insulation characteristics. But here you should be careful when choosing, since not every foam is suitable for these purposes. The closest to the foam in terms of performance and often used is extruded polystyrene foam. This material is also not afraid of moisture, has a flammability class from G1 to G4, and also has a thermal conductivity coefficient of 0.05 W / m * K. Among the shortcomings of expanded polystyrene, its synthetic origin and rather high price should be noted.

For those who prefer to build from absolutely environmentally friendly materials, suitable as thermal insulation granulated paper, foam glass, reeds,straw or seaweed ladders. The listed materials have excellent thermal conductivity, are environmentally friendly, but, like any other material, each of them has its own drawbacks. Foam glass is too fragile. Reeds, straw and seaweed are flammable and require skill in their use. Granular paper requires special equipment and skills.

How to properly insulate a mansard roof

All work on the insulation of the roof of the attic comes down to preparing the space for thermal insulation, laying and fixing materials in place. To do this, do the following:

even at the stage of erecting rafters, you need to worry about the step with which they will be installed. The step itself should be chosen one that will maintain the reliability of the roof structure and at the same time allow you to place mats or thermal insulation slabs between the rafters;
if a thermal insulation material is used that is not susceptible to moisture, then a vapor barrier is not required. Otherwise, for example, for mineral wool, a layer of vapor barrier is laid over the rafters;
a counter-lattice and a crate are stuffed, on which a layer of a waterproof vapor-transparent membrane is laid. The gap that will be obtained between the counter-lattice and the insulation will perform the functions of ventilation. In addition, ventilation ducts can be installed in the roof;
inside, between the rafters, thermal insulation is laid and fixed there. But there is one important point here. The rafter leg is made of either wood or metal, in any case, the thermal conductivity of the rafter is much worse than that of the thermal insulation material. Therefore, the rafter serves as a cold bridge. To protect yourself from this, another continuous layer of thermal insulation is equipped on top of the already laid thermal insulation and rafters. Unfortunately, this will hide the rafters, to which other elements of the attic structure will be attached in the future. And to facilitate further work, it should be noted where the rafter passes;
a layer of vapor-permeable film is laid on top of the thermal insulation and everything is fixed with an internal crate.

Video: how to insulate a mansard roof

Today, the attic is popular with owners of country houses. But many pay too little attention to its insulation and remain disappointed after living in it for some time in summer and winter. But, understanding the purpose of roof insulation and equipping it according to all the rules, you can experience all the positive aspects of living in a country house with an attic.

Let's say right away that all the wood that is used in the construction of the roof must be treated with antiseptics. Indeed, everything: both battens and counter-battens, and rafters. All wooden parts. It is also necessary to make them less flammable. To do this, they are treated with flame retardants. All elements that are located on the side of the street are treated with compounds for outdoor work. Treat all wooden parts facing the inside of the room with impregnations for interior work. If you use the composition for outdoor use indoors, the specific smell will remain for several years. If on the contrary, the wood outside may suffer: the degree of protection is insufficient. So don't skimp on this.

Proper attic insulation

If the sloping roof is at the same time the walls of the attic floor, the pie will be as follows (from inside to outside):

internal lining (drywall or lining);
crate;
vapor barrier;
insulation (the thickness of the insulation depends on the region and the parameters of the insulation, for central Russia it is about 200 mm);
superdiffusion membrane;
ventilation gap;
crate;
roofing.

Laying waterproofing

Vapor barrier and rules for its installation

A line is drawn on the vapor barrier. It marks the border from which the next layer starts (this is the amount of overlap) and the line along which the canvases are fastened with adhesive tape

thermal insulation

The better to insulate a sloping roof - the question is complex and there is no unequivocal answer to it. Mineral wool is used, only hard, with a density of 30-50 kg / m 3. Since the mansard roof usually has a large angle of inclination, soft materials can slip. It is for this reason that it is better to take plates. Although in this case it will be necessary to adjust the pitch of the rafters to the dimensions of the insulation: it should be 10-15 mm less than the width of the plate so that the material becomes “spread” between the beams and holds well.

How to insulate a mansard roof: the order of work

We warm outside

If you do everything at once, the order of work is as follows:

With this option, it is not difficult to work with a heater: it is easy to lay it, it relies on a crate (laces).

Warming from the inside

This option allows you to move the interior decoration for the required period (useful if there is a shortage of funds). After installing the truss system, here's what you need to do:

roll out and fix the waterproofing;
stuff the crate (if necessary, a counter-crate);
install roofing material.

What is the best way to insulate a mansard roof

Styrofoam (expanded polystyrene)

EPPS brands - Ekstrol, STEREKS, PENOPLEX, URSA XPS, Technoplex, PRIMAPLEX (PRIMAPLEX), Styrofoam (Styrofoam), KINPLAST (KINPLAST), Teploizolit, GREENPLEX (GREENPLEX). While the technology is the same, there are some differences in performance, so compare when choosing.

Ecowool

A feeding sleeve is launched into the formed cavity, from which loosened cotton wool comes out under pressure. It fills all the cavities, forming a single layer of insulation.

Increasingly, when building a private house, owners are planning to use the under-roof space as an attic. It is very important to ensure the comfort of living no worse than on full-fledged floors; for this, insulation is performed. Before you insulate the attic, you must carefully study this issue.

Advantages of the attic

The attic floor is considered to be a heated room under the roof, while the height of the outer walls should be from 0 to 150 cm. Planning such a floor has the following advantages:

the possibility of an interesting design of the room;
reducing the cost per square meter of living space;
additional living space.

Drawing of the attic floor

Areas of insulation

When designing an attic space, it is necessary to think about the thermal protection of the roof and walls. Insulation of the attic with your own hands will significantly save on the construction or repair stage and fully control the process.

Insulation of the mansard roof from the inside can significantly reduce heat losses, since the heated air moves up. Thermal protection of walls can be carried out both from the inside and outside. The choice of method depends on the technology of insulation of the outer walls of the entire building. Competently from the point of view of heat engineering, mount the material from the side of cold air.

If necessary, heat-insulating material is also placed in the floor structure. In this case, the insulation plays the role of sound insulation and provides maximum comfort for living.

Wall insulation

To perform the insulation of the attic floor and guarantee the preservation of temperature during the winter period, the following materials are used:

Styrofoam;
extruded polystyrene foam (penoplex);
mineral wool (glass wool, basalt, slag);
polyurethane foam (mounting foam).

These materials are the most effective for thermal protection. If necessary, thermal insulation can be mounted from the inside of the room, but it is best to mount the material from the outside. Warming the attic from the inside with your own hands has the following disadvantages:

reduction of useful space of the room;
protection from cold only the internal volume of the building, not including external fences;
displacement of the dew point (condensation during the cold period) deep into the structure of the outer wall.

But it is worth noting that this method can be used in any weather, it does not require additional scaffolding and scaffolding. Work can be performed without special qualifications.

To answer the question of how to properly insulate the attic from the inside, it is necessary to consider the order of laying the layers. It is important to provide reliable protection of the heat-insulating material from any kind of moisture.

For this, vapor barrier and waterproofing are used. The most important rule when insulating walls and any other structures: the vapor barrier is always located on the side of warm air, and the waterproofing is always on the side of cold air. If this condition is not met, the entire wall pie as a whole will not work correctly and will soon require not only cosmetic, but also more serious repairs.

The procedure for carrying out work for all types of thermal insulation does not differ significantly. To ensure reliable thermal insulation, it is best to proceed in the following order:

cleaning and leveling the base (when using mounting foam, it is recommended to moisten the base with water from a spray bottle to improve the adhesion of polyurethane foam to the surface);
fixing waterproofing;
installation of a frame for fixing the insulation (if necessary);
installation of insulation and its fastening;
vapor barrier layer;
interior decoration of the room (for fragile materials, the installation of drywall sheets will be required).

When using extruded polystyrene foam and polyurethane foam, vapor barrier can be neglected. Polyfoam, when installed in rooms with normal humidity conditions, also does not need it.

Roof insulation

The technology of mansard roof insulation in most cases consists in laying heat-insulating material between the rafters. It is best to use the following materials:

mineral wool in the form of rigid slabs;
Styrofoam;
polyurethane foam.

It should be remembered that when working with mineral wool and polyurethane foam, the performer will need protective clothing. Thermal insulation made of polyurethane foam is held in the design position due to adhesion (adhesion) to the surface. To improve this quality, it is recommended to slightly moisten the roof elements with water before application.

When using mineral wool boards, it is best to set the pitch of the rafter legs so that the clean distance between them is 580 mm. This will simplify the installation process when using standard boards with a width of 600 mm and prevent the appearance of gaps between the insulation and wooden structures.

The joints between the foam and the rafters are filled with mounting foam or sealant. Fastening is carried out with the help of special glue or nails. The adhesive must not contain solvents (alcohol, acetone).

How to properly insulate the attic with your own hands? It is important to observe the following order of roof layers:

finishing;
crate;
vapor barrier;
rafters and insulation between them;
waterproofing;
wind protection;
crate;
roofing material.

First, the supporting structures of the roof are mounted, after which the waterproofing and wind protection are laid. After installing the upper crate, they begin laying the insulation. As wind protection and waterproofing, it is better to use special moisture-wind-proof membranes.

Laying insulation in the floor structure

To prevent increased audibility between floors, 30-50 cm of insulation can be laid in the floor pie. Installation can be carried out under a coupler or on logs. When using polyurethane foam, the installation of a log is always required. When installing foam plastic under the screed, it is reinforced with additional reinforcement with meshes, the diameter of the reinforcement is taken as 4 mm.

Calculation of the thickness of the insulation

Before insulating the attic, it is necessary not only to choose a heat-insulating material, but also its thickness. It depends on the climatic region of construction and on the thermal conductivity of the insulation. It is better to choose materials with a lower thermal conductivity value: the higher it is, the greater the thickness of the heat-insulating layer will be required. The value for private construction can be taken approximately.

You can perform a full-fledged heat engineering calculation using the fairly simple Teremok program. It is freely available and fairly easy to use. With this application, you can choose the thickness of the heat insulator or check the already accepted one.

Proper insulation of the attic from the inside will ensure the comfort of living and avoid problems during operation.

It is important to pay attention to all external surfaces equally. Thermal insulation, chosen correctly, can last a long time and reliably protect the house from the cold in winter.

How to insulate the attic: methods and technology

In order for the house to be warm, it is necessary to properly insulate the attic floor. We will tell you how to properly insulate the attic with your own hands from the inside.

Attic insulation technology from the inside

Features of insulation and materials for thermal insulation of the attic from the inside with your own hands
Do-it-yourself attic insulation methods
The procedure for insulating the roof and walls of the attic
Wall insulation

An attic is an attic space equipped for people to live or for any household needs (greenhouse, office, etc.). Depending on what the room is intended for, its layout and the type of roof of the attic can be of different configurations, but the general requirements, in accordance with which the attic must be insulated from the inside, remain the same.

The layout of the insulation in the roof of the attic.

Features of insulation and materials for thermal insulation of the attic from the inside with your own hands

You need to understand that this room, unlike all the others, is colder, because. on top it does not have any "thermal cushion". That is why the insulation of the attic of the house from the inside, performed by oneself, should be of especially high quality. Based on this, you should also choose a heater, with the use of which insulation will be performed.

The difficulty lies in the fact that the surfaces are uneven, because. under the roof there are rafter beams that will have to be bypassed. The waterproofing layer will need to be brought under the roof in order to drain the condensate. In the process of organizing work on the insulation of the roof and walls of the attic from the inside with your own hands, it is necessary to take into account that the end walls also need to be covered, because. It is through them that a huge amount of heat escapes.

Scheme of attic insulation.

Each private house has its own characteristics, shape and configuration of the roof, the material of the walls and roofing. Therefore, for each individual house there may be some special, clarifying recommendations, according to which it is necessary to carry out the insulation of the roof and walls of the attic of a private house from the inside with your own hands. In order for the insulation to be of high quality and reliable, you need to choose the right materials. The choice of material with the use of which it is better to insulate the roof and walls of the attic of the house from the inside with your own hands depends on many factors: roof construction, roofing material, climate in the area, etc.

Styrofoam is one of the least expensive and most popular materials with which you can insulate the attic of a private house from the inside with your own hands. It is easy to process and install. However, it is characterized by a small vapor permeability, which means that the room can be damp. So, if the attic will be used as a living space, it is better to insulate it with other material.

You can correctly and efficiently insulate a residential attic with your own hands using polystyrene foam. When laying this material, there will be practically no joints.

Mineral wool is an excellent material in all respects.

Having high strength, basalt mineral wool is fireproof, practically does not conduct heat and does not absorb moisture. Since this material has elasticity, it holds well at the installation site, resting on the edges of the rafters. So it is best to insulate the walls of a residential attic from the inside with this material. you will be able to properly insulate your home with mineral wool, even if you have never worked with this material before.

In addition to insulation, it is necessary to arrange waterproofing, vapor barrier and ventilation system. A properly installed waterproofing membrane will perform the following functions:

ensure the protection of structural elements from atmospheric precipitation;
prevent the penetration of moisture into the insulation.

Waterproofing must be laid on a layer of insulation. Among the waterproofing films, the following are distinguished:

diffusion and breathable superdiffusion;
anti-condensation waterproofing.

The vapor barrier consists of several layers of reinforced polyethylene film, which provides good protection of the structure from condensate.

The ventilation system is needed in order to ensure the outflow of exhaust and inflow of fresh air, and to effectively maintain normal air humidity in the attic room.

Do-it-yourself attic insulation methods

Attic insulation scheme.

There are several methods, according to which you can properly insulate the attic of the house from the inside with your own hands.

Insulation between existing rafters is one of the most commonly used methods. With this method, the insulation is laid directly on the waterproofing, to the entire height of the rafter legs. The slabs should be 10-15 mm wider than the gaps between the rafters.

Thermal insulation over rafters. It is immediately necessary to carry out all the finishing work from the inside, and lay the heat-insulating material on the rafters under the roofing.

Another popular way is to insulate the attic under the rafters. This method is not used in residential construction and for low-rise buildings, but for industrial buildings it is the best option.

There are also combined schemes. The most popular scheme includes insulation under the rafters and between them. At the same time, the rafters themselves completely overlap. The vapor barrier film must be laid on top of the layer of thermal insulation material. Among the shortcomings, one can single out a slight decrease in the usable space of the attic itself. This method of insulation is more effective, however, it is also more complicated in the device. In this case, the insulation is performed with a complete overlap of the rafters and beams between the beams and from the outside of the roof.

The procedure for insulating the roof and walls of the attic

Attic insulation scheme: insulation, vapor barrier, waterproofing.

To insulate the attic with your own hands, you will need the following materials and tools:

foam sheets or mineral wool;
waterproofing film;
wooden bars;
vapor barrier film;
scissors;
sharp knife;
construction stapler;
nails;
assembly foam.

First of all, waterproofing must be laid along the rafters. The film is laid over the entire height - from the bottom to the roof ridge. However, this is not done in all cases, because roofing material sometimes also performs the functions of such an insulator. If the coating is made, for example, from roofing iron, it will be quite enough. In the process of installing a heater, you need to know the coefficient of its thermal conductivity. This data is usually given in the product certificate. Based on this information, you should decide whether 1 layer will be enough or whether you need to do double styling.

When installing this material, you need to remember that some distance should be left between it and the roof. This air gap is necessary to ensure high-quality ventilation at the installation site of the insulation. The thickness of the air gap depends on the material of your roof covering. If the material has a wavy shape (metal tile, tile), then the air gap must be at least 25 mm. In cases of using a “flat” format (steel sheets, rolled materials, asbestos cement), the distance between the insulation and the roof must be doubled.

Another important point is that the thickness of the insulator plates and rafters can be different. In case the plates are “thinner”, the first layer is laid between the rafters, and the second one must be laid on the rafters. If the slabs are thicker, wooden slats must be stuffed onto the rafters.

To protect the thermal insulation material from excessive moisture, a vapor barrier must be applied from above. As you know, warm air tends to rise and condense there. That is why the device of such protection is mandatory. As a material for the vapor barrier layer, polyethylene film, glassine, foil materials, roofing felt are used. You need to know that the vapor barrier material is overlapped, and the places of such joints must be sealed (most conveniently with adhesive tape). Fastening, as a rule, is made using thin wooden slats.

Wall insulation

The walls of the attic are insulated if the roof of your house does not reach the floor of the attic. First, you need to fix the rails on the walls for laying the heat-insulating and vapor barrier layers. The procedure for performing work is similar to that described above, however, here you must first lay the waterproofing material. For finishing the walls of the attic, fiberboard sheets have proven themselves very well as a heater. It is quite easy to work with them, because. they can be fixed with screws or nails.

Do-it-yourself high-quality attic insulation of the house can significantly reduce heating costs, creates a favorable microclimate in the house and increases the service life of structural elements.

Insulation of the attic from the inside with your own hands (photo and video)

Insulation of the attic from the inside can be done in different ways, depending on the features of the house, the configuration of the roof. In order for the insulation to be of high quality, you need to choose the right material.

How to properly and how to insulate a mansard roof

The roof is one of the most important structural elements of a building. It is exposed to various environmental factors. Protects the house from high and low temperatures, precipitation, solar radiation. If the roof is not insulated in accordance with building codes, heat loss through the roof can reach a third of the total heat loss of the house. Insulation of a mansard roof is not such a simple process as it might seem, although it is doable with your own hands. If your house has an attic floor, the question will inevitably arise how to insulate the attic roof. Many owners prefer to make an extra room there. First, it increases the total living area of the house. And secondly, there is a new original room. During the construction of modern cottage settlements, attic rooms are planned initially. But even in old houses, you can easily convert the attic with your own hands into a living space.

The insulating material used for the attic roof, in addition to keeping the house warm, protects against acoustic vibrations. Therefore, it is important to decide how best to insulate the attic roof.

Do-it-yourself attic insulation

First you need to decide how to insulate the roof of your attic. To date, there are many options for thermal insulation materials. Mounting them is easy to do with your own hands.

There are many nuances in the installation of the roof itself. The walls of the attic room are either the gables of the building or the slopes of the roof, or are adjacent to the slopes. That is why the intensive movement of air through the roof begins. Because of this, it is constantly exposed to temperature changes. To avoid the above problem, attic insulation must be carried out in sequence (from the inner layer to the outer layer):

Attic insulation scheme

Vapor barrier layer.
Heat insulating layer.
Ventilation gap.
waterproof layer.
Directly roofing material.

If high-quality insulation of the mansard roof is carried out, then the absence of the above layers is not recommended. Of particular note is the role of the heat-insulating layer and the ventilation gap. It is thanks to the presence of all layers that the microclimate in the attic room is provided.

What to look for when choosing a heater

When choosing a heater, you should first look at thermal conductivity. This is the ability to give and absorb heat between the attic space and the surrounding air. A material with low thermal conductivity is desirable. Firstly, it will contribute to better protection of the house from heat leaks. And secondly, a thin layer of heat-insulating material is required.

Properly insulated attic

On the other hand, if the attic roof is not adequately insulated, problems begin in winter. During the winter months, the roof is covered with a layer of snow. Snow is a good additional heat-insulating layer. But with insufficient insulation with your own hands, heat is lost through the roof. The snow is gradually melting. A layer of ice forms. Ice is unable to retain heat. It has a mechanical effect on structures. Including on the outer covering of the roof. This leads to its wear and gradual destruction. Sometimes because of this, it is required to repair the outer roofing layer after each winter. With sufficient thermal insulation, snow does not melt and does not turn into ice in winter. The roof retains its structure, and the snow provides additional protection against heat loss. In summer, the situation is reversed. Under the influence of direct solar radiation, the roof tends to heat up and a suffocating atmosphere is created. If you lay a layer of insulation in sufficient quantities, this problem will not be, and a comfortable environment is provided in the attic.

The main characteristics of heaters

When deciding how to insulate the attic roof of a house from the inside, in addition to thermal conductivity, it is necessary to pay attention to several more important parameters of the insulating material. The most important characteristics:

water resistance;
weight;
fire safety;
durability;
material thickness;
environmental characteristics;
terms of operation.

Moisture resistance is usually specified by the manufacturer of a particular material. It is an important parameter, since the roof can leak and get wet. Therefore, it is desirable to choose a material with water-repellent properties. If this is not available for one reason or another, then the layer will have to be additionally waterproofed. The weight of the material is also of great importance. The smaller it is, the better. The total weight of the material is determined based on its relative density. Mineral wool materials should be with a density of 45 to 50 kg / cubic meter. When using fiberglass, the density should be within 20 kg/m3. Heavier materials will put excessive pressure on structures.

Insulating layers must be non-combustible. This is usually reflected in the technical documentation. As for durability, the ability of the insulation to maintain its shape for many years is important. After all, the roof can be multi-pitched. If the insulation is deformed, the roof will simply lose its protective properties.

What materials are popular

It is necessary to disassemble each separately in order to decide how to properly insulate the roof of the attic. Main materials:

Styrofoam;
extruded polystyrene foam;
polyurethane foam;
mineral wool;
glass wool.

The better to insulate the attic roof, you decide. But before that, you need to familiarize yourself with each material.

Insulation of the attic with foam

Styrofoam- this is a demanded material among people who are faced with the problem of how to properly insulate a mansard roof. It has suitable thermal conductivity, low density and, accordingly, low weight. Polyfoam provides good protection against water, it is quite inexpensive. On the other hand, it has certain disadvantages. Its main disadvantage is the lack of fire safety. Also, when installing with your own hands, it often crumbles. As a result, gaps appear between the rafters. This, in turn, leads to a decrease in the thermal insulation characteristics of the coating. Styrofoam also has a short service life.

Attic insulation with extruded polystyrene foam

Has the best features. Firstly, it is non-combustible and provides the necessary fire safety. Doesn't crumble over time. Has water repellent properties. The advantage is also that a very thin layer of material is needed. The material is not recommended to insulate living quarters.

Attic insulation with polyurethane foam

polyurethane foam differs from the previous options in the way of laying. This leaves no gaps. The material retains its shape very well. It has the necessary fire safety and repels moisture. The disadvantage of polyurethane foam is the poor ability to pass vapor. Because of this, there may be increased humidity in the attic room. The problem is solved by the organization of adequate ventilation.

Mineral wool and glass wool commonly known as insulating materials. They have many advantages. Excellent fire safety, keep heat well, have a low density. Do not leave cracks and gaps when laying. The material provides excellent sound insulation, has a low price. The disadvantages include high moisture absorption and vapor absorption.

Laying heat-insulating material

When insulating the attic, do not forget about hydro and vapor barrier

After selecting the material, it is necessary to prepare the premises for installation. Insulation of the attic roof begins with determining the step of laying the insulation. We must try to ensure that the sheets of insulation fit closely between the roof rafters. This will avoid the formation of gaps and further heat loss. If you are using foam, then this nuance does not matter to you. Waterproofing is laid with an overlap between the rafters and the crate. Then, with the help of screws, wooden panels are installed to provide ventilation. The insulating material itself is mounted directly on the created platform between the rafters.

This is useful when attaching various structures in the attic room.

Do-it-yourself insulation of the mansard roof from the inside: technology analysis

How to properly insulate a mansard roof from the inside of the room. What is the best way to insulate? We make a choice and follow a simple step-by-step method of thermal insulation.

Construction of houses

Every year more and more of our compatriots fall under the temptation to equip a residential attic in their house. This makes it possible to expand the living space and adds some romance to the overall concept of the house, especially if you install skylights. Almost all new country houses are initially built with an attic, but even in old houses, cold attics are remodeled by compassionate owners, insulated, heated and equipped. In order for the attic to be warm and dry in winter, cool in summer and the materials last for a long time, it is necessary to understand the very essence of the attic floor insulation technology and understand the processes taking place in it. It is not difficult to do the insulation of the attic roof with your own hands, all the work is quite simple, you only need a partner and a tool. The main thing is to do everything right, then the heat-insulating material will last a long time, the wood of the rafters will not get wet and will not rot, and as a result, an early overhaul will not be needed.

Why is attic roof insulation necessary?

The attic is a special room, its walls are almost closely drawn to the roof surface and the ventilation gaps are no more than 10 - 15 cm. That is why the attic quickly cools down in winter and heats up in summer. The entire area of the roof is, as it were, an accumulator of solar heat in summer, and most of the heat goes through it in winter. This is due to the thermal conductivity of the materials from which it is made, and ventilation. For example, in winter, the heat coming from heating radiators rises, spreads under the roof and safely escapes, since the roof material has a high thermal conductivity. At the same time, the snow melts, turns into ice and destroys the roofing material. And in summer, the surface of the roof heats up and transfers heat to the entire structure, as a result, even the air becomes hot and stale. Two air conditioners will not cope with such a problem.

In a house with a classic cold attic, the situation is quite different. In it, the function of a heat insulator is performed by snow on the roof in winter and air in the attic. Backfill insulation materials on the floor of the attic plus the air contained in the attic room perfectly contain the heat coming from the residential heated room. As a result, even in the most severe winters, the temperature in the attic does not fall below 0°C - -2°C. Thanks to this, the snow on the roof does not melt and serves as an additional heat insulator. In summer, the air temperature in the attic can be regulated by opening and closing the windows in the gables, in fact, this is a real ventilation that removes excess heat from the attic, preventing overheating of the structural elements of the roof.

What to do with the attic? It is necessary to carefully insulate the room, choosing the right material, its thickness, installation location and comply with the technology. For example, if you use a heater of insufficient thickness - by eye, then it may not be enough, the snow will melt, and soon you will have to re-roof the roofing material, since the old one will become completely unusable. A sufficient width of the insulation will completely isolate the attic room from the roof, and well-executed ventilation will remove excess moisture and condensate from the under-roof space. But first things first.

Mansard roof insulation materials

Choosing the best heat-insulating material for mansard roof insulation is a very responsible task. It depends on the type of insulation how thick the “pie” of insulation will be and the number of layers in it. Due to the specifics of the place where the material will be used, certain requirements are imposed on it:

Low thermal conductivity. It is advisable to take a material with a coefficient below 0.05 W / m * K.
Low moisture permeability. Due to the fact that the roof can leak, the insulation material must be moisture resistant and, if possible, not get wet or lose its properties when wet. If this condition cannot be met, then the insulation must be waterproofed to prevent wetting.
The low weight of the insulation is extremely important so as not to overload the roof structure. You can determine the weight of a material by its density. To insulate the attic, you can use mineral wool insulation with a density of 45 - 50 kg / m3, fiberglass - with a density of 14 kg / m3. Heavier plate options (200 kg / m2) will not work.
Fire safety. It is desirable that the material does not burn and does not support combustion.
The ability to keep in shape. Since the place of laying the insulation is unusual - between the rafters at an angle, over time, light roll materials based on mineral fiber can slide down, leaving large gaps at the top - empty spaces. Therefore, it is important to choose a material that will retain its shape and dimensions for a long time.
Resistant to extreme cold, temperature fluctuations and the ability to withstand multiple defrost/freeze cycles.
Durability.

The thickness of the attic insulation is calculated for each case individually. This can be done using a special online calculator. For the calculation, it is necessary to indicate the region of construction, the thickness of the walls of the house and their material, the thickness and material of the wall insulation, the thickness and material of the floors of the house, as well as the thickness and material of the insulation of the floors. All this is extremely important for calculating heat losses, on the basis of which the thickness of the insulation is selected. If you select “by eye”, then in most cases mineral wool with a layer of 250 mm is enough.

Consider the most popular materials that are used to insulate mansard roofs.

Mineral wool or glass wool- one of the most successful solutions for insulating the attic from the inside, although not ideal. Mineral wool perfectly fits into the space between the rafters, leaving no gaps, does not burn and does not support combustion, weighs little and serves as an excellent heat insulator. Slab positions of basalt wool perfectly keep their shape. But at the same time, it absorbs moisture quite strongly, like any cotton wool, therefore, waterproofing from the side of the roof and vapor barrier from the side of the living room are required, since mineral wool vapor also absorbs well. Wet mineral wool loses up to 60% of its properties irrevocably, and its complete replacement is required. In addition, over time, it cakes and crumbles, it does not withstand mechanical loads well.

However, mineral wool remains one of the best materials for do-it-yourself mansard roof insulation. It is inexpensive, easy to work with, and following the right technology will level out its shortcomings. For different regions, the thickness of the insulation is calculated individually, but the minimum layer of mineral wool for the middle zone of the Russian Federation is 150 mm, in colder regions the thickness must be increased to 250 - 300 mm.

Styrofoam or Styrofoam- an extremely popular material on the market, with which they try to insulate everything, and what is possible and what is not worth it. Against the background of seemingly ideal characteristics - low thermal conductivity, negligible weight, moisture resistance and rigid shape, the foam has significant drawbacks. Firstly, different grades of expanded polystyrene have different degrees of fire safety from G1 to G4. And as practice has shown, for some reason combustible polystyrene G3 - G4 is used for insulation, which can end very badly. After all, the fire spreads upwards, if the attic insulation material catches fire, it will be unrealistic to survive in it. Secondly, working with polystyrene is not very convenient, since it crumbles when cut and installed, there are gaps between the rafters that have to be closed in all sorts of tricky ways. Thirdly, the foam plastic begins to crumble and collapse over time. Given all the shortcomings, it is not worth doing the insulation of the attic roof with foam plastic. This material can only be used in areas where it will be hidden behind a floor screed or a layer of plaster.

Extruded polystyrene foam- an excellent material for insulating the attic from the outside, i.e. if you lay it on the rafters under the roofing material. It is strong enough, not afraid of moisture, does not burn, keeps its shape perfectly. And what is important - it requires a very small layer of 50 to 100 mm.

polyurethane foam- a modern material that is blown using a special installation, leaving not the slightest cracks or gaps. This is an indisputable plus, especially since with such a coating it is easy to avoid cold bridges in the form of rafter legs. Polyurethane foam is not afraid of moisture, does not burn, weighs little and keeps its shape perfectly. But he has another drawback - low vapor permeability, he practically does not "breathe" at all. This means that the attic room will always be unpleasantly damp if forced ventilation is not provided.

Ecowool- one of the most ideal options in the question of how best to insulate a mansard roof. It is also blown into all cracks, is not afraid of moisture, practically does not burn, weighs little, “breathes” and, most importantly, is absolutely environmentally friendly, unlike all other materials. Its fumes or random particles are not capable of causing harm, unlike mineral wool.

When choosing a heater for a mansard roof, pay attention not only to the characteristics of the material itself, but also to the purely design features of its use. For example, laying mineral wool between the rafters allows, if necessary, to disassemble the "pie" of insulation and check the condition of the rafters, repair them, and then the mineral wool slabs can be easily replaced. If polyurethane foam is sprayed into the space between the rafters, then the rafters become practically inaccessible for revision. So everything needs to be treated wisely.

How to properly insulate a mansard roof from the inside

The most common way to insulate the attic is from the inside, if space allows or there are no other contraindications. To do this, use heaters based on mineral wool, glass wool and, less often, extruded polystyrene foam. Even less often blow out polyurethane foam or ecowool.

The scheme of insulation of the mansard roof from the inside

Compliance with the correct "pie" of mansard roof insulation is the key to the durability of materials and the comfort of living in an attic room.

Mansard roof insulation pie (from inside to outside):

Finishing material.
Vapor barrier membrane.
Insulation - mineral wool or glass wool.
A waterproofing membrane that releases steam and does not allow moisture to enter.
Ventilation gap with crate.
Roofing material.

Vapor barrier film it is necessary to use it if there are wadded materials as a heater. So the mineral wool can be protected from the damp vapors of the living quarters. If polyurethane foam or ecowool is used instead of mineral wool, then vapor barrier is not needed.

Waterproofing needed in any case, regardless of the insulation used, it will protect the wooden elements of the roof structure. As a waterproofing, it is necessary to use superdiffusion membranes that can release steam to the outside and not let moisture in. Between the waterproofing film and the roofing material, a ventilation gap of 4 to 10 cm thick is required, depending on the type of roof. Through it, excess steam will come out of the heater.

Laying insulation between the rafters of the mansard roof

Insulation of the mansard roof from the inside is best done at the stage of building a house. Then all stages of work will be performed correctly. Before starting the insulation, it is necessary to determine where we will insulate. To do this, we draw a drawing of the attic with the exact dimensions and note where the interior space will be finished. For example, if the living space will occupy the entire area, including the roof slope up to the ceiling, then the entire roof slope must be insulated. If the room is, as it were, cut off, i.e. below, between the slope and the interior trim, there will be free space, then it will be necessary to insulate strictly according to the drawn scheme, leaving free space for ventilation. But then in narrow areas near the very edge of the roof it will be necessary to insulate the ceiling.

Consider the option of insulating the entire roof slope:

Even at the construction stage, before laying the roofing material, it is necessary to waterproof the roof. To do this, we lay a waterproofing membrane on top of the rafters, starting from the bottom up, making an overlap of at least 15 cm and gluing the joints with self-adhesive tapes. The film must be spread out without tension so that it does not tear when frost sets in. It must be laid with a sag of no more than 2 cm per 1 m. We nail the waterproofing to the rafters with a construction stapler. If this is not the case, then galvanized nails with a wide hat can be used.
From above we nail a crate of wooden bars. Their thickness is selected depending on the required size of the ventilation gap, at least 2.5 cm. We fix the crate with corrosion-resistant self-tapping screws. In order not to injure the film once again, we make holes in the bars in advance.

Important! For greater reliability, two ventilation gaps can be made: between the insulation and waterproofing, between the waterproofing and the roof. This will protect the material from getting wet if condensation suddenly accumulates on the film.

We lay roofing material on the crate - tiles, corrugated board, slate, metal tiles. Here, for the installation of a soft roof, you first need to nail sheets of chipboard or moisture-resistant plywood on top of the crate, which will serve as the basis for fastening.

Works are moved inside the attic room. We unpack the insulation - mineral wool and let it lie down and straighten up. Cut into required pieces. The width should be 20 - 30 mm more than the distance between the rafters so that the canvases are held "by surprise".

We push the insulation sheets into the space between the rafters. We press on the middle of the canvas, and the edges straighten themselves. The thickness of the rafter should be 200 - 250 mm.

Important! It is convenient to select the step between the rafters according to the size of the future insulation. Rolls are sold with a width of 1200 mm. The step can be made 1200 mm or 600 mm, then the roll will need to be cut in half.

On top of the insulation we lay a vapor barrier material with an overlap of 10 cm, glue the joints with adhesive tape. We fix to the rafters with brackets or with the help of a crate.
We fill the crate of slats with a thickness of 25 mm.
We fix the finishing material on the rails.

If you plan to insulate the attic in an old or already built house and do not want to remove the roofing material, then you can cheat a little. The waterproofing film can be spread inside the attic, wrapping it around the rafters and leading into the space between them. But in this case, the wooden rafters are unprotected in case of leaks.

Laying insulation under the rafters of the mansard roof

A little less often, the method of insulation is used, when the material is laid inside the attic on top of the rafters, and not in the space between them. The main reason is that this way you can avoid cold bridges, which are wooden rafters. And so a snug fit of the heat-insulating material will ensure the absence of gaps, and the free space between the rafters will serve as additional ventilation. A very good solution if the attic space allows you to reduce it by at least 30 cm on each side.

Insulation of the attic from the inside of the room:

From the inside, we nail the waterproofing membrane to the rafters.
We fasten plasterboard ceiling hangers to the rafters so that they look at each other with their U-shaped hole.

We put a heater in the suspensions. We cut the canvas with a slight overlap to eliminate the appearance of cracks. The result should be a continuous sheet of insulation. We outline along the way where the rafters are located.
We close the insulation with a vapor barrier film, fasten it with brackets.
We fill the crate for finishing material. For fixing, we use long nails 150 - 200 mm to break through the insulation and reach the rafters.

In principle, this method can be combined with laying insulation between the rafters. The first layer will be between the rafters, and the second will cover everything, including cold bridges.

How to insulate a mansard roof from the outside

It is possible to insulate the roof from the outside only at the construction stage or if the roofing material is removed. This method of insulation allows you to leave the attic space in its original form without losing space. Also, many design solutions involve the use of rafters as decorative elements of the decor.

Mansard roof insulation technology from the outside

Insulation of the attic from the outside is carried out only with dense slab materials. These include extruded polystyrene foam or Penoplex. It is not afraid of moisture, so it does not require vapor barrier. The "pie" of Penoplex insulation will look like this:

Extruded polystyrene boards.
Waterproofing membrane.
Ventilation gap with crate.
Roofing material.

The undeniable advantage of this method of insulation is that the rafters are available for inspection and repair at any time.

Laying insulation on the rafters of the mansard roof

Insulation with extruded polystyrene foam over the rafters allows you to create a continuous heat-insulating layer without cold bridges.

To prevent the material from sliding off the roof, at the very bottom we nail a board to the rafters, with a width equal to the thickness of the insulation (from 50 to 100 mm).
We spread the insulation boards in a checkerboard pattern. You need to start from the bottom, from the fixing rail.
We fix them to the rafters with the help of special dowels with a mushroom cap.
We spread the waterproofing film, starting from the bottom up, with an overlap of 10 - 15 cm, glue the joints with adhesive tape. The film is necessary to protect the material from leaks and condensation.
We fill the crate of bars with a minimum thickness of 40 mm.
We install roofing material.

Extruded polystyrene foam does not require any additional protection from the inside.

It is necessary to insulate the gables of the attic room together with the entire facade of the building, i.e. outside. The choice of insulation material depends entirely on the material from which the house is built and the preferences of the owner. For example, if insulation is carried out using a curtain wall system, then mineral wool with vapor barrier and waterproofing films can be used. And if a wet facade is planned, then foam can be laid under it. Don't forget that technology is the key to success.

Do-it-yourself insulation of the mansard roof, Construction Portal

Construction of houses Every year more and more of our compatriots fall under the temptation to equip a residential attic in their house. This makes it possible to expand the living space and