The best insulation for a mansard roof. Insulation of the attic roof: the material used and the features of its installation. Insulation protection from external and internal moisture

The question of which insulation is better for the attic is relevant for those who decided to equip a living space under the high pitched roof of a private house. The attic differs from an ordinary room at home by increased heat loss. This is due to the fact that usually it does not have capital external walls without window openings, and on both sides and from above the room is separated from the street only by a roofing system of small thickness.

Mineral wool insulation

Criteria for choosing insulation for the attic

High-quality insulation allows you to make the attic suitable for year-round living. When choosing a heat insulator, you need to pay attention to the performance characteristics of materials, including compare:

soundproofing properties;
ease of installation;
moisture resistance;
resistance to biological destruction;
lifetime;
profitability;
environmental friendliness;
fire safety.

But the main quality by which the material for insulation is assessed is its coefficient of thermal conductivity, on which the ability to retain heat in the room depends.

From the point of view of ease of installation and use of insulation, preference should be given to universal materials. If the same heat insulator can be used for walls, roofs and floors, the insulation of all structures will last the same period.

Soundproofing properties are an especially important parameter if the roofing flooring is made of metal (seam roofing, metal tile, corrugated board). Gusts of wind, rain and hail make such a roof "sound", and staying in the attic will be uncomfortable.

Plate heaters from a well-known manufacturer

Since the roof frame is usually assembled from wood, it is advisable to use insulation that is resistant to fire and does not spread combustion. Otherwise, an accidental ignition will lead to the fact that the entire attic and roof will quickly be engulfed in fire.

So that condensation does not form on the wooden structures of the truss system and pediments and the insulation does not lose its thermal insulation properties due to moisture penetration, it is necessary to insulate the attic room with a vapor and moisture proof material, or use a reliable hydro and vapor barrier. This affects the speed and laboriousness of the installation of the insulating layer, affects the preferences when choosing a material.

Insulation thickness

Table 1. Dependence of the thickness of the insulation on the coefficient of thermal conductivity

The manufacturer indicates the thermal conductivity coefficient on the packaging of the material. This indicator depends on the production technology and the density of the insulation. The table below shows the average values:

Table 2. Coefficients of thermal conductivity of some heaters

Polyurethane foam and ecowool are modern materials that can be used as a heat insulator for attic rooms, but their installation requires the use of specialized equipment, inviting specialists. The rest of the popular heat insulators are produced in the form of plates or roll materials of various densities and thicknesses.

Insulation is cut along the width of the span between adjacent rafter legs (or the gap between the battens on the walls) and a bullet is inserted. If the estimated thickness of the insulating layer exceeds the width of the rafter leg, bars of a suitable section are packed onto the rafters from the side of the room.

The most effective is two-layer insulation - after the gaps between the rafters are filled with a heat insulator, another layer of roll material (it is possible with a foil vapor barrier outer surface) is attached over the rafters with solid butted strips. This will eliminate the formation of cold bridges.

Laying the heat insulator between the rafters

Let's take a closer look at the main pros and cons of popular heaters that are suitable for thermal insulation of the attic roof and gables.

Fiber roll and slab insulation

glass wool;
mineral wool;
stone (basalt) wool.

Their key advantage and disadvantage at the same time is the ability to pass steam. In theory, humid, warm air from the attic will escape through the breathable inner lining, heat insulator and roof system, which will help maintain a favorable indoor climate. In practice, however, there are the following difficulties:

an increase in the moisture content of fibrous insulation leads to a sharp decrease in its thermal insulation properties;
the insulation that has gained moisture (especially glass wool) is crumpled, deformed, forming cold bridges;
the wood of the truss system begins to rot from contact with moisture.

To avoid these problems, it is necessary to mount a vapor barrier on top of the insulation from inside the room. And between the roofing and thermal insulation, a waterproofing material must be laid.

Roofing cake with waterproofing over insulation

Air exchange through the fiber insulation will be carried out only if the waterproofing and vapor barrier layer is made of special gas-permeable membranes. The vapor barrier should allow air to pass through, but retain moisture from the room. A gas-permeable waterproofing barrier must release moisture from the insulation and prevent water from entering it.

Membrane materials are much more expensive than conventional or reinforced film, roofing material or glassine. But these investments will justify themselves due to the durability of not only insulation, but also the roof truss system.

Super diffusion membrane

If a film is used as a vapor barrier, this will reduce the cost of construction, but this will nullify the important advantage of fiber insulation - gas permeability. Do not use perforated film, as it allows steam to pass through, which will accumulate in the insulation.

Performance characteristics of fiber insulation

Glass wool. Its positive qualities include:

fire safety (2 degree of fire resistance);
environmental safety (does not contain resins);
unattractiveness for mice (do not build nests and passages);
affordable price.

The main disadvantage is that when working with the material, sharp glass dust is formed, the installation of the heat insulator requires accuracy and the use of protective equipment. In addition, over time, glass wool tends to deform, crumple, especially when moisture penetrates.

Mineral wool... The composition of the material includes fibers of various origins (material of manufacture - clay, stone, quartz sand, glass, etc.). Mineral wool is characterized by a multi-layer heterogeneous structure with air lenses. Due to this, the material dampens sound waves well. It is recommended to choose mineral wool (primarily Isover, Ursa) for those who have decided to make metal roofing.

Such a heat insulator is fire-resistant, does not rot, and is easy to assemble. But rodents can settle in it, whose nests, passages and waste products reduce the operational properties of the insulation.

Basalt wool... Consists of fibers obtained by melting rocks. Withstands heating up to 1000 degrees, does not spread combustion. Basalt wool should be chosen carefully, checking the certificates of quality and safety: some manufacturers, in an effort to reduce the cost of products, use resins that emit toxic substances.

Basalt wool

Basalt wool is resistant to fungus, but can be damaged by rodents. This is a good noise isolator, easy to install. But when choosing a material for insulating a rafter system, one should take into account the rather large weight of stone wool slabs.

If you have to choose a fibrous heat insulator, pay attention to the density of the material. The heat insulator should not lose its shape even after prolonged use. For mineral, basalt wool, the density indicator should be about 40-45 kg / m3.

Polymer materials for insulation

Choosing a polymer heat insulator for the roof and walls of the attic. It can be polystyrene, extruded polystyrene foam (these two types of insulation are produced in the form of sheets and plates of different thicknesses), as well as polyurethane foam, which is applied to structures by spraying.

The advantages of polymer insulation include low weight and low thermal conductivity. Such insulation will not overload the rafter system and will successfully cope with the task of retaining heat.

The disadvantages of polymer insulation include extremely low vapor permeability. Gas exchange is not carried out through the insulated structures, therefore, one cannot do without a well-thought-out ventilation system in the attic.

Attic insulation with polyurethane foam

Thermal insulation made of extruded polystyrene foam (foam) and polyurethane foam will not allow heat and steam to pass to the roof truss frame, therefore, there is no need to install a vapor barrier from the side of the room. Despite the fact that the dew point during the internal warming of the gables will shift towards the heat insulator, moisture that is dangerous for wood will not condense.

All joints and abutments of foam insulation must be filled with polyurethane foam and (after removing excess foam) glued with reinforced tape so that the insulation layer is airtight.

Manufacturers produce penoplex of various densities. For pitched roofs and attic walls, where heat loss is high, it is advisable to use slabs with a density of 30-35 kg / m3.

If you decide to choose an inexpensive foam plastic, it is better to install insulation according to the same principle as fiber board materials. Unlike extruded polystyrene foam with a continuous closed-cell structure, the foam consists of many individual granules pressed into a board. Technological pores remain between the structural elements, which are capable of passing steam to wooden structures.

The suitable density of the foam is 35 kg / m3, at a break, the material should not crumble into individual balls. Since the foam smolders during a fire with the release of toxic substances and it is easily gnawed by mice, this is not the best material for internal insulation.

Polymeric insulation for the attic should not be considered as a soundproofing material for the roof - it will not save rain drops from knocking. But if you insulate the floor with it, it will reduce the vibration load from steps, creating acoustic comfort in the rooms under the attic.

The chosen insulation option will last for many years if you purchase good material and take into account all the subtleties of its installation.

The attic floor is often used for housing, so it is necessary to carry out the insulation correctly in order to create comfortable conditions. The technology is similar to similar work in any other room, but the peculiarity is that the attic is separated from the street by gables and a roof, and not by main walls. All surfaces need to be insulated, and since they differ in the device, the installation of the insulation is carried out in different ways.

The better to insulate the attic roof

Usually, on the attic floor there are no load-bearing walls with high thermal insulation characteristics, therefore, the insulation of the roof and gables should be carried out especially carefully and efficiently. This is the only way you can feel comfortable and cozy in the attic both in summer and in winter.

If we compare the roof of the attic room and the main walls, then it is clear that it cannot compete with them in thermal insulation. In addition, the roof cannot withstand heavy loads. All this must be taken into account when choosing a heater.

Correctly insulated attic space can significantly increase the living area of the house

In order to maximize the useful volume of the attic floor, the following rules must be adhered to during its construction:

to reduce the load on the rafter system, light roofing materials are chosen, in this case it is not recommended to use natural tiles;
to reduce the layer of roofing cake, modern and effective thermal insulation materials are chosen;
special attention is paid to the organization of ventilation of the roofing space, otherwise moisture will accumulate in the room and the thermal insulation properties will deteriorate.

Correctly performed ventilation and waterproofing of the attic roof allows moisture to be removed from under the roof space, which ensures effective thermal insulation and a long service life of the materials used.

For a mansard roof, it is necessary to choose lightweight materials.

The number of layers required and the thickness of the heat-insulating "pie" depend on the choice of insulation. The attic has its own design features, so the insulation must meet the following requirements:

have low thermal conductivity, experts recommend using materials with a coefficient below 0.05 W / m * K;
due to possible roof leaks, the insulation must be moisture resistant and lose a minimum of its properties after getting wet;
have a small weight so as not to overload the rafter system, it depends on the density of the material, which should be in the range of 14-50 kg / m 3, it is not recommended to use denser insulation;
should not burn and support combustion;
since the thermal insulation material is laid on the roof, this requires that it keep its shape well and does not slip over time, forming gaps;
withstand significant temperature changes, not be afraid of frost;
have a long service life.

Insulation materials

For the insulation of the attic roof, the following materials are most often used:

Mineral wool. This is an excellent solution, it does not burn and does not support the combustion process, it is easy to fit, has a low weight, and high thermal insulation characteristics. In addition, mineral wool has an affordable cost, therefore it is popular and in demand. Depending on the region where the building to be insulated is located, the thickness of its layer can be from 150 to 300 mm. The main disadvantage is that this material absorbs moisture well, so you need to make high-quality waterproofing.
Mineral wool can be in rolls and mats, it is more difficult to insulate the roof with roll materials
Styrofoam or expanded polystyrene. This material has a low weight, good thermal insulation characteristics, low moisture permeability, but its main drawback is a high degree of fire hazard. During the laying of the foam, it crumbles, so there are gaps that must be additionally repaired. After a while, the foam, unprotected from external factors, begins to gradually deteriorate, therefore experts do not recommend insulating the attic with this material.
To insulate the attic, it is necessary to use polystyrene with a thickness of at least 50 mm, if necessary, it can be laid in several layers
Extruded polystyrene foam. This is a good insulation for carrying out these works, since it is durable, not afraid of moisture, does not burn and keeps its shape well. A sufficient layer of material is 5–10 cm. Extruded polystyrene foam has low vapor permeability, therefore, in order to create comfortable conditions in the attic, it is necessary to correctly supply and exhaust ventilation, and this is additional time and costs. In addition, the price is higher than that of conventional foam.
When insulating a roof with extruded polystyrene, good ventilation is required
Polyurethane foam. For installation, special equipment is used, which allows you to apply the material without cracks and gaps. It has good thermal insulation characteristics, light weight, does not burn, moisture-proof, but its disadvantage is low vapor permeability. Without the organization of forced ventilation, it will be uncomfortable to be in such a room due to high humidity.
It will not be possible to carry out the work on insulation with polyurethane foam on your own, since you need professional equipment
Ecowool. This is the most suitable material for attic insulation. It is also applied without gaps, penetrates into all cracks and fills them well, is not afraid of moisture, does not burn, has a low weight and good vapor permeability, and is environmentally friendly. In addition to the high cost of this material, it will not be possible to insulate the attic with ecowool on your own, therefore, you will have to invite specialists to perform the specified work.
Special equipment is used to apply ecowool
Foil materials. They not only insulate the room, but also reflect heat. In order for such materials to effectively fulfill their purpose, the mirror layer must be directed towards the inside of the attic. A gap of about 5 cm is left between the insulation and the vapor barrier.
Foil insulation is used for hydro, heat and noise insulation

In each case, the choice of the most effective insulation for the attic must be approached individually. When using mineral wool, the heat-insulating "pie" can be disassembled, the condition of the rafters can be assessed and, if necessary, repair work can be carried out, and then everything can be put back in place. If sprayed materials were used, then it will not work to inspect the rafters.

The better to insulate the roof of the attic from the inside

When choosing materials for insulating the attic from the inside, the climatic conditions in which the house is located are taken into account. Each material has its own pros and cons. The most popular and affordable material with which the attic is insulated from the inside is basalt wool. Installation is carried out in several layers, while the seams are overlapped. Usually a layer 15–20 cm thick is sufficient.

Basalt wool is laid in several layers

Professionals often use polyurethane foam. It has high adhesion, so there are no gaps left after application. Polyurethane foam has high thermal insulation characteristics, so it is applied in a smaller layer, unlike other materials, which will need much more. But keep in mind that the cost of the specified material is high and installation will not work without special equipment. Polystyrene foam plates are often used, the thickness of the required layer will depend on the density of the material used.

If you carry out the insulation of the attic roof from the inside on your own, then it is best to use expanded polystyrene, basalt or mineral wool, since they are easy to install. Often they are combined: first, mineral wool is laid, and then expanded polystyrene plates.

How to properly insulate the roof of the attic

The technology for carrying out these works is not difficult, especially if the insulation is carried out with mineral wool. During the installation of thermal insulation, personal safety measures must be observed: be sure to wear tight and closed clothing, use glasses, gloves and a respirator.

Sequence of work:

Preparatory stage. All wooden surfaces are well treated with antiseptics, metal parts are coated with anti-corrosion impregnation.
Treatment of wooden roof elements with an antiseptic can significantly increase their service life
Fastening waterproofing. A waterproofing film is fixed on the rafters, and a crate is mounted on top. The waterproofing material is laid with an overlap between the battens and the rafters, all seams are glued with a mounting foil, for example, "Ondutis BL" or "Ondutis ML". First, the tape is attached to the canvas located at the bottom, this is done 5–6 cm from the edge, then the protective layer is removed from the tape and the upper canvas is fixed. The material is laid from the lower roof slope. First, the film is fixed with a stapler, and then wooden counter-battens are installed to create a ventilation gap. You can fasten the slats to the rafters with nails or powerful staples, but it is better to do this with self-tapping screws. Then proceed to the installation of insulation.
Insulating layers are laid in a certain sequence.
Insulation installation. Insulation is laid between the rafters, work starts from the bottom and gradually moves up. In order for the insulation to fit snugly, its size should slightly exceed the distance between the beams. To fix the insulation, use special anchors or frost-resistant glue. This applies to roll and panel insulation, such as mineral wool, polystyrene foam and expanded polystyrene. Ecowool and polyurethane foam are applied using a special installation, so there are no empty voids left.
Mounting the vapor barrier. After laying the last layer of insulation, the vapor barrier is installed. It is mounted on a wooden lathing, laid on a heat-insulating layer. It is not necessary to tighten the vapor barrier membrane too much, it should sag by 2-3 cm, this will ensure the presence of a ventilation gap between the thermal insulation and the outer finish.
The final stage is the installation of finishing materials. To do this, a crate is made over the laid vapor barrier, you can use wooden slats or a metal profile, and already on it, using special screws, sheets of drywall, plywood, chipboard or lining are fixed.
Installation of drywall is carried out on a metal or wooden crate, which is attached to the rafters on top of the vapor barrier

When installing the insulation, the slabs should be tightly adjacent to each other, and to eliminate cold bridges, it is recommended to lay a second layer with overlapping joints.

Useful tips for choosing and installing various types of insulation:

if mineral wool or fiberglass is used, then to ensure high thermal insulation characteristics, their layer should be 15–20 cm;
basalt wool can withstand temperatures up to 1000 ° C, does not absorb moisture, but it is damaged by rodents;
A 2.5-centimeter layer of polyurethane foam in terms of its thermal insulation characteristics corresponds to an 8-centimeter layer of mineral wool;
A 15-centimeter layer of ecowool in terms of thermal insulation characteristics corresponds to a 50-centimeter layer of wood;
in order for the rolled or slab material to lie tightly between the rafters, its width should exceed the distance between them by 1–2 cm.

Features of installation of insulation for the attic roof

When designing a building with an attic floor, it is necessary to correctly calculate the distance between the rafters in order to ensure maximum structural strength. When installing insulation between the rafters, it is necessary to lay the material end-to-end so that there are no gaps, otherwise cold bridges will form.

Only the correct laying of all elements will allow you to effectively insulate the attic

During the installation of waterproofing, all work is carried out from the lower roof slope and the material is overlapped. It is recommended to lay another continuous layer on top of the insulation mats, which will completely cover the rafters. Wooden or metal rafters have a higher thermal conductivity than insulation and are cold bridges. If you close them with insulating material, it will be inconvenient to mount the finishing elements. To simplify this task, it is necessary to mark the location of the rafters during the installation of the last layer of insulation.

If we talk about the insulation of the attic roof from the inside, then not all materials are convenient to mount, roll insulation is almost impossible to install normally. To strengthen the rafter system, various connections are often used, which complicate the installation of the insulating layer.

Video: insulation of the attic roof from the inside

Insulation of the attic pediment from the outside

When insulating the gable from the outside, most specialists and home craftsmen use extruded polystyrene foam or ordinary foam. To carry out these works, scaffolding will be needed, since it will be difficult, long and tedious to do everything with the help of a ladder.

The gable insulation technology from the outside consists of the following stages:

First, the walls are prepared. To do this, they are cleaned of dirt, and then primed. The primer will allow the adhesive to perform better. It is recommended to prime in two layers, the second is applied after the first has dried.
If you plan to use a finishing material such as siding, then to fix it, you need to make a crate. It can be made of wooden beams or galvanized profiles. The height of the lathing should correspond to the thickness of the insulation used.
To make it easier to install the foam, the step of the crate should be equal to the width of the sheet, then the material will fit tightly and waste will be minimal
A sheet of foam in the corners and in the center is lubricated with glue and pressed for 30-35 seconds to the surface of the pediment.
If the foam is plastered, then it is better to additionally fix it with plastic dowels.
If the foam is plastered, it must be fixed with dowels, and if siding is being mounted, then fixing with only glue is enough
After laying the insulation, a waterproofing film is attached. If the lathing is wooden, then this is done with a stapler, and it is fixed to the profile with a counter lattice, on which the siding is then attached. To create a gap between the waterproofing and the decorative finish, the thickness of the battens should be 20–30 mm.
At the last stage, the siding is installed or the foam is plastered and then painted.
Both metal and vinyl siding can be used to finish the gable.

Video: insulation of the attic pediment

It is not difficult to insulate the attic with your own hands, it is enough to have basic knowledge and skillful hands. If we talk about the warming of the pediment, then when using a curtain facade it is better to take such an insulating material as mineral wool. If the facade is wet, then it is better to insulate with foam. Only with the observance of the developed technologies and the correct implementation of the stages of work on the attic insulation will the expected result be obtained. If everything is done correctly, then you can use the attic as a living space throughout the year.

Equipping the roof with insulation is one of the most important stages in the construction of a roof, which is designed for long-term operation.

External insulation

This process is not complicated and is carried out according to the following algorithm:

Primarily the rafters from the bottom side hemmed with plywood or edged board.
After that carry out the laying of a layer of thermal insulation... The surface of the layer and the joints are glued with foil tape. It is very important to lay the vapor barrier on the right side, because this material is able to function in one direction.
Next, the insulation material is laid... In this case, free space should be avoided, it is necessary that the insulation should lie tightly.
The next step is layout of the hydro-barrier on top of the rafter structure... Bonding is also carried out with a specialized tape.
Penultimate make ventilation gaps... This process is carried out using a rail, which is placed on top of the hydro-barrier. The height of the rail is selected depending on the parameters of the roofing. If the roof is of a corrugated type, then the standard of the slat is 20-30 mm, if the roof is of a flat type, then 50 mm.
The last carry out the installation of the lathing and lay the roof.

Considering that the material does not have protection from precipitation, the work should be carried out only in clear weather.

External insulation

Insulation of the attic roof from the inside

At first glance, it can be decided that this method of insulation is more reliable and practical due to the fact that precipitation does not fall on the material, because protected by a roof covering.

However, this method has disadvantages.:

It is very inconvenient to install most of the material from the bottom side up, and it is impossible to fix roll materials in some places;
In the rafter system, there are elements to strengthen the structure, the mating points of which are not protected by heat-insulating material.

Stages of installing a heat-insulating layer internally:

Installation starts from the bottom of the roof and a film with waterproofing properties is laid with an overlap, held together with adhesive tape. In places located near walls, the coating should have a larger margin, which is adjusted after the completion of the entire process.
Equip the structure with counter rails, which are attached to the rafter system with nails. This is necessary to ensure the ventilation gap and tight adhesion of the layers to each other.
After that carry out the installation of insulation.
The last step is vapor barrier membrane equipment, which is fixed with overlapping construction brackets.

CAREFULLY!

It is not recommended to seal cracks and gaps with construction foam. In order to avoid unnecessary distance between the sheets, it is best to stack them with a margin of 5 m.

Internal insulation

Conclusion

Which installation method to choose for arranging an insulating structure for a mansard roof largely depends on the individual parameters of the structure. Initially, you should fully study all the nuances and conditions.

Useful video

In this you will learn how to properly insulate a mansard roof:

In contact with

The modern building materials market is replete with a variety of insulation materials. But when the question concerns full-fledged thermal insulation for a house, you need to know the main requirements for insulating materials. In this article, we will tell you which insulation is better for the attic and what characteristics of the material you need to take into account so that in winter your house is warm and cozy.

Your insulation must be durable and resistant to external factors.

Any builder with experience in roofing work will tell you that the roof of the house must be properly insulated. When choosing a material, focus primarily on the characteristics and needs of the structure. We live in a temperate climate, the characteristic features of which are heat in summer and severe frost in winter. This means that your insulation must be durable and impervious to external factors.

One of the key criteria in the choice is the thickness of the insulation for the attic, on which the reliability and durability of the structure depends. For the cold northern regions, you will have to choose heat insulators as thick as possible, but for residents of the southern regions, where the air temperature does not drop much below zero in winter, you can choose those that are thinner and lighter.

Video about attic insulation

The most versatile insulation is based on mineral wool. It is relatively inexpensive, but suitable for almost all weather conditions. Although in some cases it is worth using polyurethane or another more expensive material that is able to fill the empty space more densely.

We do not recommend using a backfill heat insulator for roof insulation. Its thermal conductivity is quite high, which is why it simply cannot fully protect your home from the cold. It is much better to choose a roll or slab insulation for a mansard roof with low thermal conductivity.

Manufacturers, as a rule, set their own recommendations for installing insulation. If you follow them, you can significantly increase the service life and reliability of the structure. All currently available materials differ in the way they are installed, depending on their weight, appearance and other characteristics.

It is best to choose insulation that weighs little, but at the same time is strong and tough enough. You also need to remember the density of the material.

It is best to choose insulation that weighs little, but at the same time is strong and tough enough.

In our climatic zone, snowfalls are very frequent in winter, so it is necessary to take into account the load from the snow cover. Heavy weight on the roof can lead to significant deformation. As a result, the thermal insulation deteriorates greatly. As a result, you will have to deal with the work on the insulation of the home again. And this is not only a big waste of time, but also money.

You also need to take into account the slope of your roof. The smaller the angle, the more snow will accumulate on it in winter, and when it rains, the more likely it is to leak.

The roof is one of the most important structures in the house. We advise you to make the choice of material strictly according to the following criteria:

Expect severe frosts in winter. At the same time, the thermal insulation layer must withstand them. When there is a sharp change in temperature, the material should not distort, crack or sag.
Take seriously the indicators of moisture resistance and fire safety. Even with direct exposure to fire, it should not ignite. Today on the construction market you can find materials with fire retardants that prevent combustion and slow down the spread of fire. We strongly recommend using just such. If we talk about the dangers of moisture, then when the insulation is saturated with water, its properties are greatly deteriorated. Water itself is an excellent conductor of temperatures, so a wet insulation simply will not perform its functions. In addition, when soaked, the material is strongly deformed and gains weight, and the entire roof structure is under heavy load.
The chosen insulation should keep its shape as efficiently as possible. It is better for the material to be complete, without unnecessary seams, than to insulate the mansard roof of the house with piecewise debris in order to save money. See that you don't have to pay twice - such material will not be able to fully fulfill its functions and even the most beautiful room in the attic will be uncomfortable due to blowing from under the roof.

The selected insulation should keep its shape as efficiently as possible.

There are really a lot of materials on the market. Among the most popular are fiberglass, mineral wool and polystyrene boards. But they are already quite outdated. We do not recommend using them. Today, much better quality products and liquids are being created that tightly fill the voids and isolate the room from the cold.

Basically, the heat loss when using modern means is reduced by 50% or more. Plus, it saves you money on other materials. For example, foam glass is extremely resistant to moisture, which eliminates the need for a waterproofing layer. Foam glass is also characterized by a very low thermal conductivity and impermeability to vapor particles. But consider other options.

Video about the attic insulation process

Polyurethane. It is sold in a liquid state, but when you apply it to a surface, it hardens and becomes very durable. As with foam glass, waterproofing is also not required. It is very convenient for mansards with complex structures, where it is almost impossible to work with standard materials. All empty space is completely filled with foam, ensuring low thermal conductivity. Excellent performance properties, long service life and general ease of application are the hallmarks of modern polyurethane. The polyurethane board is blown out with the help of a special machine and they are waiting for it to harden. It's easy even without building experience.
Ecowool. One of its main advantages is environmental friendliness. It is made from exclusively natural materials. This is mainly ordinary cellulose. In addition, many manufacturers add fire retardants and active antiseptics to the material, which make the ecowool protected from fungus and mold. And it must be said that in comparison with other materials, it costs an order of magnitude cheaper. Even a layer of 20 cm can cope with the worst weather conditions. If you cannot decide how best to insulate the attic from the inside, then this is one of the most affordable and practical options. When using ecowool, it must be precisely adjusted to the dimensions of the compartments between the rafters. It fits in two layers for better heat conservation. But do not forget that it is sensitive to moisture, which is why a waterproofing layer must be installed.
Polystyrene and other hard materials. Working with them is somewhat more problematic. They need to be laid on a crate or rafter structure. But with proper blowing, it is polystyrene that provides the best thermal insulation of the attic.

With proper blowing, it is polystyrene that provides the best thermal insulation of the attic

Remember that improper insulation can cause many additional problems - roof icing, icicles, etc. Therefore, it is very important not only to choose the right way to insulate the attic from the inside and outside, but also to competently carry out all the work on installing thermal insulation.

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 its operating conditions. After all, the living space is somewhat different from the cold attic. About which insulation is better for the attic roof, we analyze in detail in the material below.

If you do not know which insulation to choose for the roof of the attic (what are the requirements for 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 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 the potential occupant of the upper rooms of the house will breathe with.
Low weight of insulation. The mass of material will form the overall 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.
The density of the insulation. The level of possible deformation under the influence of sedimentary load directly depends on its density. So, snow lying on the roof can deform the insulation material with its weight over time. And even when the infusion descends from the roof, the soft insulation with low density will no longer restore its structure. In addition, 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. It is worth choosing here depending on the climatic conditions of the region. If snow predominates, then you can give preference to a denser cover. And if the priority is winds, then less dense thermal insulation 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 flammability level.
Good moisture-repellent properties. It is important to understand here that the attic insulation will be exposed to fumes from inside the room. And with an incorrectly laid vapor barrier or its deformation, the material can accumulate moisture. And this over time can lead to its deformation, which will reduce the level of thermal insulation.
Good sound insulating properties. This is because the sound of rain on a mansard roof can be disturbing to occupants underneath. Especially if the roof is covered with corrugated sheet or metal. Although it is better not to do this for upper living quarters.
Inertness to biological microorganisms. That is, the insulation for the attic roof should not rot and mold. Otherwise, the same vapors will poison the residents of the upper rooms.
Low thermal conductivity. This is the most important criterion that will allow you to limit heat loss from the room through the roof space.

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

Overview of attic insulation

Below is a rating of thermal insulation materials for the attic roof. We will start with the most optimal ones, and end 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 for the insulation of 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 under-roof space will be minimal.
Non-flammability. 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 moisture-repellent impregnation, which is applied to basalt fibers in the production of ecowool.
Good sound absorption. Under the insulated stone wool roof, you will sleep soundly and comfortably.
High strength of the slabs. Even a long-term static load will not deform the stone wool.
The ability to pass vapors through itself without wetting the structure of the material. That is, stone wool breathes in a simple way, circulating air in space.

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

Extruded polystyrene foam

If you do not know what is the best insulation for the roof of the attic, then you can use this type of foam. It is worth remembering here that extruded polystyrene foam can have different densities. And the higher it is, the heavier the coating slabs will be. It is worth knowing that for high-quality insulation of the roof, the thickness of the insulation for the attic should be at least 10 cm. At the same time, it is strictly forbidden to use nitro-based paints and varnishes for insulation with expanded polystyrene. From such mixtures, the insulation will undergo deformation, which means that its thermal insulation properties will come to naught over time.

Distinctive advantages of extruded polystyrene foam are:

Excellent moisture resistance;
Inert to microorganisms and chemicals;
High sound insulation;
Excellent thermal insulation properties;
Non-flammability.

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

Penofol

Quite modern insulation material made in the form of rolls. Gradually, this insulation replaces the usual roll of mineral wool. The features of this coating 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 for use in windy but snowless regions.

Liquid polyurethane

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

The advantages of the material are:

Good sound insulation properties.
Low thermal conductivity due to the cellular structure.
Inertness to aggressive environments.
Environmentally friendly (however, when spraying and 10 minutes after the procedure, you should be 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 can become overgrown with condensation if the vapor barrier is improperly organized;
Loses its basic properties in direct sunlight;
Flammable and smoldering.

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

Styrofoam

This is a budget option for insulating the attic roof perimeter. At the same time, polystyrene plates are easy to install, perfectly insulate and do not require knowledge of special complex laying technologies. However, it is worth paying attention to the fact that 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

Roll material, which has long been familiar to masters, is used less often today for insulating walls and roofing space. 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 installed practically without waste due to the possibility of cutting it, you should always remember that this insulation is capable of accumulating moisture. This means that when wet it will increase its mass. This puts a lot of stress on the roof frame. In addition, wet mineral wool insulation from rolls can slide down over time, which will form cold bridges.

Important: solid insulation such as expanded polystyrene or extruded polystyrene foam must be laid over 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.