Do-it-yourself attic roof insulation. What insulation to choose for a mansard roof. Mineral thermal insulation materials

But if it is properly equipped, then it will make a wonderful living room. However, we should not forget that this room needs not only an interesting finish, but also high-quality insulation. After all, in summer, thanks to the large roof area, the room heats up quickly. In winter - instant cooling. Therefore, if you decide to equip an excellent room, initially familiarize yourself with how to insulate the roof of the attic from the inside.

Key Features

When insulating the attic, it is necessary to consider high-quality thermal insulation. At the same time, the room under the roof has many features that should be considered during the repair.

roof configuration. Most often, the roof has an inclined surface. It is rare to find a strictly horizontal roof. Accordingly, the heat-insulating layer will have to be laid on an inclined plane. Solid sheets will not cause any particular difficulties. But with soft rolls you have to work hard.
Thermal insulation. For roofing, wood or other lightweight materials are usually used, which are characterized by water-repellent characteristics. But such a roof often does not have sufficient thermal insulation. You can often see gaps in the wooden crate. And this provides even more heat loss.
Gable insulation. The attic consists not only of the roof. Therefore, do not forget about the frontons. Attic insulation will not provide the necessary thermal insulation if you do not insulate these walls.
Vapor permeability. Steam condensate rising from the rooms accumulates under the roof. Therefore, when choosing insulation for the roof, be sure to choose a material that has excellent vapor permeability.
Safety. Since the attic will become a living space, then choose an eco-friendly material. It must be non-flammable and completely fireproof. In addition, this material should not be harmful to health.

The choice of insulation

Initially, you should determine what material you will use. After all, the thickness of the thermal insulation and the number of required layers depend on its technical characteristics. Therefore, warming from the inside, start with the study of suitable materials.

The modern market provides the widest range of heaters. Consider the most popular of them.

Foam insulation

The material is a fairly convenient means for laying on inclined surfaces. In addition, if you decide to insulate the roof of the attic from the inside with your own hands using foam, then the cost of such repairs will be quite affordable. After all, the price of the material is relatively low.

The advantages of this heater are:

low thermal conductivity;
light weight;
ease of installation.

A foam attic, despite the advantages described above, also has a number of disadvantages that this material gives it. Therefore, before choosing such a heater, familiarize yourself with them.

The main disadvantages of foam are:

insufficient vapor permeability;
when ignited, it releases toxic substances;
attractive to rodents.

Mineral wool

This material is often used for insulation. Mineral wool consists of synthetic and combined with stone chips.

The material has the following advantages:

small price;
high thermal insulation;
environmental friendliness;
light weight;
fire safety (mineral wool does not burn);
high vapor permeability.

Thinking about which attic insulation to choose, many owners prefer mineral wool. After all, this material is distinguished not only by its excellent characteristics. It is very easy to mount it.

Professionals say that you can not even use fasteners. It is enough to cut out the plates, the dimensions of which are 2-3 cm larger than the distance between the rafters. Such pieces fit perfectly between the crossbars and will not fall out.

Extruded polystyrene foam

This is another material that can be used to insulate the attic. It is produced in the form of certain plates with a porous texture.

The advantages of the material are:

high strength;
moisture resistance;
excellent thermal conductivity.

However, along with the advantages described above, expanded polystyrene has serious disadvantages:

high flammability;
air tightness;
the ability to release toxins during combustion or oxidation (provoked by heat);
high cost.

Given such moments, it is extremely rare that the attic is warmed from the inside with polystyrene foam. Most often, this material is used for gables. At the same time, it is often used for facade work. After all, expanded polystyrene does not absorb moisture and does not let it through.

Application of polyurethane foam

This is a liquid insulation for the attic. It can be applied to any surface without any problems. This material will become an indispensable solution for roofs with complex configurations.

However, to work with such material, a protective suit and a special installation are required. That is why polyurethane foam insulation is most often entrusted to hired specialists. Of course, the cost of work increases many times.

But it is polyurethane foam that creates a monolithic continuous layer that does not let the cold through. In addition, such a surface does not need additional vapor barrier layers.

Use of environmental materials

Today, many owners choose heaters that are highly safe for both human health and the environment. They practically do not contain chemical fibers and do not emit toxic substances during combustion.

Such materials are:

ecowool;
ecolen;
fabric cotton insulation.

The main advantages of such heaters are the following properties:

high quality thermal insulation;
ability to pass air;
high sound insulation;
hypoallergenicity;
excellent air filtration.

roofing cake

So, if you decide to insulate the roof of the attic from the inside with your own hands, then you need to familiarize yourself with the intricacies of installation in detail. In order for the room to become livable, it will be necessary to form a certain roofing pie under the roof, consisting of several layers.

Consider it in detail, starting with the inner surface:

Drywall. This material is almost always used to decorate the walls of the room.
Vapor barrier layer. It provides condensate outlet to the outside. It is recommended to perform vapor barrier with a special membrane. It is overlapped (approximately 10 cm), and glued on top with adhesive tape. The vapor barrier layer must be continuous, not containing any cracks or gaps.
Crate. This is the next layer of the roofing pie. It performs several functions at once. The crate supports the insulation. In addition, it is the basis to which they are attached. And it is this layer that provides an extremely important gap for ventilation under the roof.
Insulation. It is located above the crate. Depending on the selected material, as well as on the planned end result, the insulation can be laid in one or several layers.
waterproofing layer. It is designed to protect the insulation from getting wet. The layer is important enough. When planning how to insulate the attic roof from the inside, be sure to remember the need for waterproofing. So you protect the insulation from premature damage.
Crate. This layer is necessary to create a ventilation space between the waterproofing film and the roof. This gap allows moisture that has accumulated on the water-repellent membranes to vent. However, it is important to provide for the possibility of condensate evaporation. To do this, special holes are made at the base of the slopes. Their value depends entirely on the chosen material for the roof. For example, roofs covered with tiles, corrugated board, need holes, approximately 25 mm. And for roofs with flat materials, the size of such holes increases to 50 mm.
Windproof vapor barrier. It is mounted above the second crate. It allows you to provide warmth and comfort indoors even with the strongest wind. This insulation is laid over the rafter legs and carefully secured with battens.
Roofing. This is the final layer of the roofing cake.

Warming technology

Having dealt with the varieties of materials, having carefully studied what the roofing pie consists of, you can proceed directly to work. So, let's consider how to insulate the roof of the attic from the inside on your own.

The most popular material is still mineral wool. It is often used for such purposes. That is why we will analyze how to properly insulate the attic roof from the inside with mineral wool.

The technology of work consists of the following stages:

Training. Initially, try to protect yourself from various kinds of problems. Check if the room is sufficiently ventilated. Stock up on protective equipment. They are: a respirator, construction gloves, goggles.
Checking the rafters. This is the next stage of your work. Now you need to check how evenly the rafters are located. This task is carried out using an aluminum long profile. It should be attached to the rafter legs. The bars, installed correctly, will completely come into contact with the profile.
Measuring the distance between the rafters. Take measurements in at least 2 different locations.
Preparation of mineral wool slabs. Now you can start working with the heater. To do this, using the measurements taken earlier, slabs of the appropriate dimensions are cut out of mineral wool. However, remember that the dimensions of such fragments should be approximately 2-3 cm larger than the measurements you took. This will ensure good placement of the plates between the rafters and eliminate the need to fix the insulation with additional fasteners.
Mineral wool installation. To lay the insulation, it is slightly compressed and placed in a niche between the rafters. The mineral wool should return to its original shape. If wrinkles or bubbles form, be sure to level the material. This continues the insulation from the inside of the entire surface. The place where the wall is combined with the extreme rafter is sealed with sealant.
Installing vapor barrier. When laying a special film, fix it with a stapler (in increments of 15-20 cm). Overlap individual fragments, and glue the joints with a special tape.
Decoration of window openings. They are equipped with special structures made of wooden bars, maintaining a distance of 40-60 cm. Vertical slats are fixed with self-tapping screws. Under them, a base is drawn up, which will then become the junction of the drywall with the film. The frame is filled with insulation. On the slopes it is covered with a film.
Insulation of attic walls. It's time to think about frontons. They are insulated in the same way as the roof. Carefully work out the ends of the roof. Now create a metal frame on which drywall will be attached. Insulation is again laid between such parts. From above it is closed with a metal profile.
Mounting It is attached to the frame with electrical tape and glue. Installation of drywall occurs with the help of self-tapping screws.

Attic insulation with polystyrene foam

If you decide to use this material, which is, in fact, a modern, improved successor to foam, then the technology will be slightly different. If your roof is installed correctly, then a waterproofing layer is already provided.

Attic insulation with polystyrene foam consists of the following steps:

Processing of wooden elements. Start from this stage. All wooden structures must be carefully treated with an antiseptic. It is recommended to open such surfaces also with a flame retardant. Be sure to allow time for the product to soak in and dry completely. Moldy or rotten elements must be replaced.
Sheet fastening. Extruded polystyrene foam is placed in the openings between the rafters. To fasten the material, you can use staples, corners, thin slats (they are nailed across the rafters). To ensure ventilation, leave a gap between the sheets and waterproofing of 2-5 cm. Expanded polystyrene is laid very carefully, leaving no distance between the sheets and rafters. If gaps are nevertheless formed, then they are sealed with mounting foam or pieces of the material itself. Sometimes expanded polystyrene is laid in several layers. When the insulation is completely laid out, you should get a flat surface that does not contain any slots or protrusions.
Installation of vapor barrier. For the next layer, a special film is used, which may look like a perforated or foil membrane. Fasten it with a stapler, overlapping. The joints are sealed with a special tape.
Clean finish. This is the final step. Depending on your desires, you can decorate the room with clapboard, drywall, plastic or other materials. This finish is mounted close to the vapor barrier layer. If desired, you can make a thin crate, consisting of slats, and attach the selected materials for finishing on it.

Wall insulation

If in your room the roof does not reach the floor, then the room must have side surfaces. If you do not take care of the walls, then, no matter how well you insulate the roof, the attic will continue to be cold. Of course, work on a vertical surface is much easier than under a roof.

It is quite easy to insulate the walls of the attic on your own. The technology of work is almost the same as for the roof. Therefore, if you were able to insulate the roof on your own, then this task will not cause you any difficulties. So, what algorithm should be followed?

Stages of attic wall insulation:

Initially, fix special rails on the surfaces.
Now lay the thermal insulation layer.
Behind it, a vapor barrier must be provided.
Don't forget waterproofing. For walls, this is no less important than for the roof. Therefore, pre-lay the appropriate material that provides waterproofing.
Fiberboard sheets can be used as insulation for wall decoration. It is easy to work with such material. It is perfectly fastened with screws or nails.

Conclusion

Now, knowing how to insulate the attic roof from the inside, you can easily cope with this task. And even if you do not plan to use the attic for a living room, you still need to take care of the roof. After all, high-quality insulation significantly reduces the cost of heating a house. In addition, it provides a homely microclimate in the cottage. And what is important, it significantly extends the service life of structures.

If the master plans to make the attic room residential, then it is necessary to choose the right insulation for the attic. In this case, it is very important to take into account the basic requirements for the coating and the conditions of its operation. After all, the living space is somewhat different from the cold attic. About which insulation is best for a mansard roof, we analyze in detail in the material below.

If you do not know which insulation to choose for the attic roof (what requirements to apply to it), then pay attention to the following information. In order for the insulation of the attic room to serve not only for a long time, but also not to harm the residents of the house who will live in the attic rooms, the material must meet the following requirements:

Environmental friendliness. Especially when you consider that the attic rooms will be heated. And an increase in temperature provokes evaporation from the insulating coating. In turn, evaporation is what a potential tenant of the upper rooms of the house will breathe.
Lightweight insulation. The mass of material will form the total load of the construction cake on the roof truss system. And accordingly, the smaller it is, the stronger and more durable the roof will be.
Insulation density. The level of possible deformation under the influence of sedimentary load directly depends on its density. So, snow lying on the roof can eventually deform the insulation material with its weight. And even with the descent of the crust from the roof, a soft insulation with a low density will no longer restore its structure. In addition, the deformation of the coating will lead to a decrease in thermal insulation properties. However, in turn, a material with a lower density will retain heat better. Here you should choose depending on the climatic conditions of the region. If snow prevails, then a denser coverage can be preferred. And if winds are a priority, then less dense heat-insulating materials will be relevant.
Low flammability. In particular, for attic rooms it is better to use heaters marked G-1 and G-2. They have the lowest level of flammability.
Good moisture repellency. It is important to understand here that the attic insulation will be exposed to evaporation from inside the room. And if the vapor barrier is not properly laid or deformed, the material can accumulate moisture. And this over time can lead to its deformation, which will reduce the level of thermal insulation.
Good soundproofing properties. This is because the sound of rain on a mansard roof can disturb the occupants underneath. Especially if the roof is covered with corrugated board or metal tiles. Although it is better not to do this for residential upper premises.
Inertness to biological microorganisms. That is, the insulation for the mansard roof should not rot and mold. Otherwise, these same fumes will poison the residents of the upper rooms.
Low thermal conductivity. This is the most important criterion that will limit heat loss from the room through the roof space.

Important: if the insulating coating is laid on the rafter legs, then the ideal option would be a light and dense material. If the design of the upper part of the house involves the use of frame panels, then it is better to use heavier plate heaters.

Overview of insulation for the attic

Below is a rating of insulating materials-heat insulators for the roof of the attic. We will start with the most optimal ones, and end up with more budgetary and controversial ones. So, thermal insulation in the attic can be carried out using the following materials.

stone wool

It is also called ecowool. Such a coating is the best insulation to date. It is the most demanded when warming the attic floor. The material has proven itself well due to the following technical characteristics:

Excellent (low) thermal conductivity. For stone wool, it is 0.039-0.045 W / m K. Thus, heat loss from the attic space will be minimal.
Fire resistance. Stone wool does not burn or melt, which is why it is most often used for roof insulation.
Does not accumulate moisture. This indicator is due to a special water-repellent impregnation, which is applied to basalt fibers during the production of ecowool.
Good sound absorption. Under the insulated stone wool roof, you will sleep soundly and comfortably.
High strength plates. Even a long static load does not deform stone wool.
The ability to pass vapor through itself without moistening the structure of the material. That is, stone wool simply breathes, providing air circulation in space.

Important: if you decide to use a stone wool insulation layer, then you definitely need to make high-quality vapor and waterproofing of the roof.

Extruded polystyrene foam

If you do not know which is the best insulation for the attic roof, then you can use this type of foam. It is worth remembering here that extruded polystyrene foam can have a different density. And the higher it is, the heavier the coating plates will be. It is worth knowing that for high-quality roof insulation, the thickness of the attic insulation should be from 10 cm. From such mixtures, the insulation will undergo deformation, which means that its thermal insulation properties will eventually come to naught.

Distinctive advantages of extruded polystyrene foam are:

Excellent moisture resistance;
Inertness to microorganisms and chemicals;
High sound insulation;
Excellent thermal insulation properties;
Fire resistance.

Important: when insulating the attic with slab materials, all joints must be carefully sealed with mounting foam.

Penofol

Pretty modern insulating material, made in the form of rolls. Gradually, this insulation replaces the usual rolled mineral wool. The features of this coverage are:

Good sound and heat insulation;
Inertness to moisture;
Protection of the insulated room from radioactive waves from the outside.

However, it is worth knowing that such a material undergoes significant deformation under prolonged static loads. That is why penofol is ideal when used in windy but snowless regions.

Liquid polyurethane

This type of insulation is suitable for both walls and floor panels of the house. Its main feature is that liquid polyurethane is sprayed in a continuous layer, which means that the material will have no cold bridges at all.

The advantages of the material are:

Good soundproof properties.
Low thermal conductivity due to the cellular structure.
Inertness to aggressive environments.
Environmental friendliness (however, when spraying and 10 minutes after the procedure, it is worth being in a protective mask). After hardening, the material is absolutely safe for humans.
Service life is about 30 years.
Low thermal conductivity.

However, liquid polyurethane also has disadvantages:

The material may become overgrown with condensate if the vapor barrier is not properly organized;
Under direct sunlight loses its basic properties;
Flammable and capable of smoldering.

Important: with the right installation technology, liquid polyurethane mass fills even the most inaccessible places on the roof.

Styrofoam

This is a budget option for insulating the attic roof perimeter. At the same time, foam plastic plates are easy to install, perfectly insulate and do not require knowledge of special complex laying technologies. However, you should pay attention to the fact that the foam is attractive to rodents, and an open flame leads to smoldering and ignition of the insulation. If your house is a country house (not capital), and you want to better insulate the attic of a small cottage, then this option will be quite acceptable.

Mineral wool

Long-familiar to masters, rolled material for insulating walls and roof space is used less frequently today. However, during installation, the thickness of the insulating mineral wool layer for the roof should be 10-20 cm. However, despite the fact that mineral wool is laid almost waste-free due to the possibility of cutting it, you should always remember that this insulation is able to accumulate moisture. So, when wet, it will increase its mass. Thus, a large load will be exerted on the roof frame. In addition, wet mineral wool insulation can slide down over time, which will form cold bridges.

Important: solid insulation such as polystyrene foam or extruded polystyrene foam must be laid on top of the roof sheathing. If we are talking about mineral wool or ecowool, then they are placed between the rafter legs under the crate. And remember, no matter selected material alwaysneedbut strictly observe the technology of its installation.

Mansard roof insulation is one of the key steps in creating a reliable roofing pie, which is designed for a long service life. To ensure comfortable conditions for year-round living in the attic floor of the house, it is important to choose a high-quality insulation and properly install it.

Functional features of the thermal insulation layer of the roof

Properly executed insulation of the roof structure from the inside makes it possible to provide a favorable microclimate in the attic room. In the cold season, heat will be effectively stored there, and in the heat, thermal insulation will not allow overheating of the air in the rooms under the mansard roof. To create effective roof insulation, you need to understand the intricacies of the roofing pie installation technology and use high-quality materials and tools. An introductory video is helpful.

Insulation of mansard-type roofs is carried out according to the same principles as the insulation of ordinary roof structures, but increased requirements are imposed on mansard roofs. This is due to the design features of the attic rooms, the walls of which are either formed by the slopes of the roof and the gables of the house, or are closely adjacent to the slopes. For this reason, the air in the attic in the summer heat is very hot, and cools quickly in winter.

The mansard roof multi-layer cake consists of the following components (from the inner layer to the outer):

vapor barrier layer;
insulation;
gap for ventilation;
waterproofing;
roofing material.

The presence of all layers is mandatory, since each of them performs a strictly defined function. Increased attention is required for ventilation and the heat-insulating layer of the roofing pie, since the level of comfort when living in the attic floor of the house depends on their quality performance.

When choosing a heater, it is necessary to pay attention to such an indicator of the material as thermal conductivity.. It characterizes the ability of a material to transfer heat into or out of a room. The lower this indicator, the better the material protects against heat leakage, therefore, the smaller the layer of insulation can be used to achieve the required thermal insulation characteristics of the roof.

In a heated room, the greatest heat loss occurs through the roof, since, in accordance with the laws of physics, warm air rises. Heat penetrates through the roofing cake and is transferred to the top coat, which is covered with a layer of snow in winter. Snow has a porous structure, and due to internal air pockets, it acts as an external heat insulator at air temperatures below -2 degrees.

If the heat loss of the house through the roof is large, the roofing material heats up, which causes the snow to melt. When the air temperature drops, the melted snow forms an ice crust. This is dangerous for roofing, as when freezing water has a negative effect on the outer surface of the roof. Ice, unlike snow, is not a heat insulator, moreover, it is denser in structure - the ice crust on the roof significantly increases the load on structures. If the insulation from the inside is done correctly, in winter the snow on the roof does not melt.

In the hot summer period, excess heat is transferred from the roof to the inside of the room. The air can overheat so much that even air conditioners will find it difficult to maintain a normal microclimate on the attic floor. Installing a reliable heat-insulating layer from the inside of the roof will avoid such problems. Of course, the air in the attic will be heated more than in the rooms on the first floor, but the difference will not become uncomfortable.

Features of mansard roof ventilation

Mansard roof insulation requires a special approach. This is due to its design features. If we compare the device of an ordinary roof and an attic, it is obvious that the main difference is the size of the ventilation space between the living quarters and the roof. Ventilation of a conventional roof is provided by the presence of an attic with dormer windows. The ventilation space of the mansard roof is very limited - it is only about 10-15 centimeters.

Properly performed ventilation is extremely important when arranging a mansard roof roofing pie.. The ventilation gap between the waterproofing and the insulation helps to remove excess moisture from under the roof, protecting the entire structure and extending its service life. In winter, ventilation prevents overheating of the roof and the formation of an ice crust on it. In hot weather, due to the ventilation from under the roof, part of the heat is removed, thanks to which it is possible to avoid overheating of the air in the attic floor and the structural elements of the roof.

The choice of insulation

At the stage of preparation for the installation of the roofing cake, you should decide on the choice of material for insulation. The number of layers and the thickness of the thermal insulation depend on the correctly selected type and technical characteristics. A wide range of materials for the insulation of roof structures is presented on the modern construction market. Among the most requested are:

polyurethane foam;
extruded polystyrene foam;
glass wool;

Foamed glass can also be used, various types of natural insulation for installation from the inside (wood chips, seaweed, granulated paper, etc.).

There are four main criteria for choosing a thermal insulation material:

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

Note! To insulate a mansard-type roof, it is recommended to use a material with a thermal conductivity coefficient of 0.05 W / m * K and below.

The higher the moisture resistance of the insulation, the longer it will retain its functional qualities. The index of resistance to burning is an important criterion for ensuring the safety of the house. It is also important to consider the environmental friendliness of the material and its safety for humans. But the last two parameters do not affect the durability and effectiveness of roof insulation.

Mineral wool - a heater made from a melt of rocks. The material holds heat well, does not rot, is resistant to temperature extremes and aggressive environments, and practically does not absorb moisture. Mats of various thicknesses made of mineral wool are especially convenient to use for roof insulation, if the pitch of the rafters matches the width of the mat.

Glass wool is made from molten glass, in terms of its properties this type of insulation is close to mineral wool, but has a lower thermal threshold of -450°C. It has good heat and sound insulating characteristics. Glass wool is frost resistant. Moisture can accumulate between the glass wool fibers, so waterproofing must be done correctly.

Mineral wool and glass wool allow you to insulate the roof with minimal financial investment. The disadvantages include the need to create a thick layer of insulation and several layers of vapor and waterproofing.

It is possible to insulate the roof structure from the inside with the help of polymeric materials - expanded polystyrene or polyurethane foam. The advantages of polyurethane foam (gas-filled plastic) include a high ability to retain heat, lightness, and durability. Polyurethane foam does not pass steam and is not affected by moisture. Extruded polystyrene foam allows you to effectively insulate the roof - its thermal conductivity coefficient is 0.05 W / m * K. The material has hydrophobicity, does not pass steam. Flammability class from G1 to G4, depends on the brand of material. The disadvantages of polymer insulation include their artificial origin and relatively high cost.

If there is a goal to build a house exclusively from environmentally friendly materials, you can insulate the roof with natural heat insulators. Despite good thermal conductivity and environmental friendliness, various types of natural insulation have their drawbacks. Foamed glass is highly brittle. Granular paper, as well as mats made of reeds, straw, seaweed and similar materials are highly flammable and require special skills during installation.

Insulation installation technology

To understand how best to perform the installation of thermal insulation when arranging a roofing pie, you must first familiarize yourself with the step-by-step instructions for the work. In general, it boils down to the following actions:

preparation of space for the installation of insulation;
laying a heat-insulating layer;
material fixation.

At the stage of preparing the project of the rafter structure, the step with which the rafters will be installed should be determined. In this case, it must be borne in mind that the rafter system must be reliable, that is, the step should not exceed the recommended values. If the type of insulation is selected in advance, it is recommended to install the rafters in such a way that the mats or insulation boards fit tightly between them from the inside. This simplifies the insulation technology and minimizes the waste of thermal insulation material.

Above the thermal insulation, between the crate and the rafters, waterproofing is laid. The material is overlapped, laying starts from the bottom edge of the slope. Then wooden counter-battens are mounted - their thickness creates the required ventilation gap of the roof. Reiki can be attached to the rafters with nails, but it is better to use self-tapping screws. Insulation is laid and attached to the prepared structure from the inside between the rafters.

A rafter leg made of metal or wood is a cold bridge, since its thermal conductivity is much worse than that of a heat insulator.

For this reason, when insulating the attic, you should not limit yourself to installing a heat insulator between the rafters - it is better to make a continuous heat-insulating layer on top of the already laid mats and rafters. For a continuous layer, it is better to use a thinner insulation. This method improves the quality of insulation. The disadvantages include the fact that in this case the rafters are hidden, and it is more difficult to use them in the future to fasten other structural elements. To facilitate the progress of further work, the location of the rafters should be correctly noted.

A vapor-permeable film should be laid on top of the thermal insulation. Its use allows you to remove excess moisture. Then the prepared structure is fastened with a crate. At the final stage of work, the inner lining of the ceiling is performed. Properly performed roof insulation allows you to use the attic floor as a living space all year round, in which a favorable microclimate is maintained. For a detailed answer to the question of how to insulate a mansard roof, it is recommended to pay attention to the thematic video with detailed instructions.

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.

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.

Thermal insulation should contribute to maintaining a favorable atmosphere in the room. In winter, the house should be kept warm, and in summer - cool.

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):

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.

Styrofoam- this is a sought-after 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.

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.

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.

Important: installation of glass wool is carried out in closed clothing, a mask and gloves. Contact of material particles with skin and mucous membranes should be avoided.

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.

Tip: the rafters themselves let heat through. It is necessary to lay an additional thin layer of insulating material on top. Be sure to remember the location of the rafters.

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

Video: brief abstracts of proper thermal insulation with mineral wool insulation

Thus, it is not difficult to insulate the roof. To do this, you need to choose the right material that suits you. And then, in accordance with the technology, mount the insulation. As a result, a favorable climate for living will be created in the attic room.

Improving the performance properties of the roofing cake and achieving living comfort can be ensured by high-quality thermal insulation. The event is relevant if the attic floor is used for living or recreation. When planning the insulation of the mansard roof from the inside, pay attention to the need for work, the choice of thermal insulation materials, and carefully study the technological algorithm.

The need for warming measures

Thermal insulation of the attic floor is required due to its location next to the flooring surface. Exceeding the ventilation gaps by 15 cm leads to cooling of the room, and it becomes uninhabitable. Experts identify several reasons why the attic roof should be insulated from the inside:

protection from the effects of weather factors;
reduction of up to 20% of heat losses;
reduction of overheating;
regulation of air humidity and reduction of the likelihood of condensation;
the possibility of performing combined insulation.

It is also necessary to create a heat-insulating coating to prevent incandescence in the summer. Works are carried out using insulating materials, which must be selected in accordance with regulatory requirements.

How not to make a mistake when buying a heater?

The thermal insulation standards that the roof and attic room are subject to are specified in SNiP 2.3.79-1998. The same document recommends how to choose insulation for the attic roof. Quality material features:

low thermal conductivity, due to which a comfortable microclimate is maintained on the floor;
moisture resistance to prevent internal and external leakage. If the selected material is hygroscopic, waterproofing is laid;
small mass, facilitating pressure on the surface. On the top floor, it is appropriate to work with mineral wool fabrics (density 45–50 kg/m3) or fiberglass (density 14 kg/m3);
compliance with the parameters of fire safety, durability, resistance to sudden climatic changes;
the ability to maintain shape when located at a non-standard angle. Otherwise, the fabric slips, and the quality of the insulation of the structure decreases;
optimal thickness for the climate in the region of residence. Products with good density and small thickness will be universal;
environmental safety and long service life.

On the modern market there are a lot of materials with positive and negative characteristics. Each type of thermal insulation coating differs in the installation method, therefore, it is possible to determine which insulation for a mansard roof is better only by studying its features.

Varieties of thermal insulation materials

When planning how you will insulate the roof of the attic floor from the inside, it is important to choose the right heat-insulating layer. In construction, mineral wool, polyurethane, expanded polystyrene and ecowool are actively used.

Features of mineral wool materials

Mineral wool is a thin fiber based on glass or basalt. The insulation well blocks steam, condensate, retains moisture, and does not ignite. A small mass, combined with environmental friendliness and a high coefficient of thermal conductivity, justify the use of mineral wool in private homes.
When buying mineral-based cotton wool, be guided by its type:

Fiberglass can cause itching and irritation if it comes into contact with bare skin. The material is used only on an inclined surface;
basalt fibers do not ignite even at a temperature of 1000⁰С. But the chaotic arrangement of the villi makes basalt wool hard, so it is produced in the form of slabs.

In order to qualitatively insulate the roof of the upper floors, you need a material with a density index of 25. Mineral wool must be laid between the rafter frame with a layer of 15-25 cm, depending on the climate of your region.

Durable Styrofoam

Expanded polystyrene boards can be selected to provide thermal insulation for wall and roof surfaces. The material is placed between the truss system and under it. Manufacturers offer two options for expanded polystyrene:

tile foam with a granular structure. White slabs have dimensions of 0.5x1 and 1x1 m;
penoplex (polystyrene with extrusion), which is homogeneous.

Foam-based polystyrene is an excellent raw material in terms of price and thermal insulation characteristics. However, durable material has a high cost and requires additional finishing with plasterboard sheets or clapboard. When using material for an attic roof from the inside, there are risks of fire, release of toxins and gaps if the wooden frame shrinks.

Polyurethane foam application technique

Thinking over how to insulate the floor under the roof, pay attention to liquid materials - polyurethane in the form of a foamed mixture. Mounting foam is applied from a special cylinder in a dense layer. The use of foamed polyurethane eliminates seams. On large areas, high-tech installations are used, which only specialists can operate.

Ecowool - technical specifications

Ecowool is made from cellulose waste, it is a dense loose cotton wool. The material is the best insulation due to its environmental friendliness and loose structure. Safety for human health, gap closure density and moisture resistance ensure the ease of use of cellulose wool for the roof of the attic floor:

Backfilling material in dry form on horizontal surfaces in the presence of ceiling beams.
Application of a thick wet composition. Ecowool is mixed with an adhesive, and the resulting mass is applied to the frame with a spatula.
Warming by backfilling inside the roofing cake.

Cellulose cotton fractions have the ability to pass air, maintaining a normal temperature regime even in hot weather. The sorption qualities of the insulation provide high-quality absorption of excess condensate, therefore, thinking about the best way to insulate a mansard roof, stop at ecowool.
When insulating the roof of your attic, do the work in a comprehensive manner - start with the purchase of material, planning events, laying hydro or vapor barrier.

Preparing for attic insulation

To understand the process of creating a heat-insulating coating on the top floor of your own house, it is important to imagine a roofing pie. It consists of a material on the roof surface, a waterproofing layer, lathing, insulation, cornice strips, vapor barrier and rafters. When thinking about how to insulate a mansard roof, follow the sequence of work.

Laying waterproofing

Sheets of roofing felt or PVC film are wrapped around the rafters with a sagging of 3-5 cm. Thanks to this technique, moisture rolls off the roof onto a special gutter. Membrane waterproofing provides complete tightness of the structure. It is laid like this:

The material is rolled out perpendicular to the truss frame, starting from the bottom.
The first row is led into the gutter.
The second row is rolled out, observing an overlap of 10-15 cm.
On the ridge, the membrane is cut and fixed.

When working, take into account the direction of the moisture-blocking layer: one side is brought out to the roof covering, and the second - to the insulation material.

We form a vapor barrier

For optimum steam protection, a special foil membrane is required. The algorithm for its flooring is somewhat reminiscent of the previous one:

The material is rolled out, observing the overlap of the panels.
The joints must be glued with adhesive tape (in the side, upper and lower parts);
A stapler is used to fix the membrane film to the lags.

A crate of wooden lining is laid on top of the vapor barrier.

Phased thermal insulation of the attic

How to properly insulate a mansard roof yourself? Start activities some time after arranging the crate! Tasks are performed externally or internally, the use of which is determined by the degree of readiness of the object.

External method of thermal insulation

If you're building your home, then don't ignore building a heat-shielding layer in the attic. When insulating the roof of the attic at home with your own hands, follow the step-by-step algorithm of work from the inside:

Stuff the crate across the truss frame or fasten a strong galvanized wire.
From the side of the roof, lay the heat-insulating material, choosing it according to the climatic conditions of the area. Try to match the seams so that cold air does not penetrate through the gaps.
Roll out the waterproofing membrane and stuff the crate.
Glue a layer of internal vapor barrier.
Perform roofing.

The external method provides ease of laying the insulation on the formed crate wire.

Internal insulation

To insulate the attic roof correctly with your own hands, working from the inside, first install the rafters, on top of which lay the waterproofing, the crate and the roofing material. Adhere to the construction technology:

Make a barrier to prevent material from entering above the acceptable level.
Consider a way to fix ecowool or mineral wool.
Fill the planks between the wooden joists, adhering to a step of 40-50 cm to create a ventilation gap.
Place the thermal insulation, matching the seams with an overlap.
Nail the crate frame - it will hold the insulation layer.
Glue the membrane that isolates the room from steam.
Mount the crate.
Finish the room.

It is worth laying layers of mineral wool with a width slightly larger than the step between the lags. Roll out the rolled material, starting from the bottom. Rise up gradually, fixing the insulation with a stapler crosswise.

How to finish a warm attic floor?

Having warmed the attic, proceed to its interior decoration. You can mask the insulating material and create a surface for further decoration with drywall, GVL, glass-magnesium sheet or clapboard. The last option is successful if you plan to use the attic for living.
Having decorated the wood trim, treat it with fire and anti-rot agents. If you prefer GKL or LSU, screw the sheets, and then go through the places of the seams with a putty mixture or mastic.
Having learned how the attic roof is insulated, you will not only create comfortable conditions for being in the room from the inside, but also reduce costs during the heating season. Insulation, applied not in one, but in several layers, will ensure maximum heat retention in a country house, even in the harsh domestic climate.