How to properly and how to insulate the attic floor. Insulation of cold attic floors: materials and methods Insulation of a cold attic with foam

For comfortable operation of the building, it is necessary that the attic floor is well insulated to prevent the temperature of the ceiling surface from dropping below the dew point. Otherwise, moisture spots will definitely appear on the ceiling and walls, which will only worsen appearance rooms, but will also cause mold growth and the development of fungi, which are problematic to get rid of. Therefore, increased requirements are imposed on the thermal protection of the attic floor.

In accordance with the regulations, the heat transfer resistance for the attic floor must be at least the following value: Ro = 4.15 m 2 ° C / W. Attic floor country house insulated with slabs of mineral (basalt) or glass wool. Insulation boards must be laid between ceiling beams or on floor slabs. Mineral wool is laid on a vapor barrier layer or on a plastic film.

Foiled warmth insulating material placed shiny side down. The space between the beams is filled with a layer of heat-insulating material. To reduce heat loss through cold bridges, another layer of thermal insulation is laid on top of the beams.

To reduce heat loss from light fiber insulation due to drafts, it is protected with a vapor-permeable windproof material. The use of such material allows you to increase the thermal protection of the attic floor and protect the insulation from getting wet if drops of moisture fall on it (in case of damage to the roof or leaks).

From the cornice, the insulation layer must also be protected from the wind by high-density mineral wool slabs or boards that are installed on the edge.

The attic or attic rooms, divided into compartments by partitions, can be insulated in various ways.

The first way: if the attic is non-residential, then only the floors should be insulated - the ceiling of the building.
The second way: if the attic has an attic, then it is necessary to insulate, in addition to the floors, the roof.

To insulate the roof of the attic and rooms are usually used:

Construction felt.
Mineral wool in various designs.
Styrofoam.
Polyurethane foam.
Basalt, glass wool, ecowool.

Floors in the attic can be insulated with the following materials:

Construction felt, mineral wool, glass wool.
Foam boards.
Expanded clay, slag, ash, sawdust, straw, reeds.

Before insulating the attic, the joints of the floor and roof are checked, the cracks are sealed with tow soaked in lime mortar. You can also use mounting foam, silicone adhesives and sealants.

Before performing work, all wooden structures are covered with antiseptic and fire retardant compounds.

When insulating the roof from asbestos-cement sheets, special attention should be paid to gaps that are formed by waves of asbestos-cement sheets. If there are gaps, then they are filled with tow in lime mortar.

The presence of protective covers, collars and aprons is checked at the junction of asbestos-cement sheets to parapets, pipes and walls. Let the coating elements on the protective floors be at least 15 cm.

Insulation of the attic with various materials

To insulate the attic and attic in a private house, different heaters are used:

polystyrene foam
polyurethane foam
expanded clay
felt, etc.

The process of insulation is the same for all materials, so consider the insulation of the attic using the example of mineral wool.

Before starting the attic insulation, it is necessary to waterproof the roof. Mineral wool is versatile and easy to use, has low thermal conductivity and density, and withstands high temperature and insensitive to aggressive environments. Mineral wool is also an excellent sound insulator.

Attic slopes can be insulated with mineral wool slabs and mats. The plates are more rigid, and the mats are elastic, this property helps to lay them better and denser. Foil-coated mineral wool mats are also used for vapor barrier.

Since usually the thickness of mineral wool is greater than the thickness of the rafters, overlays are made on them to increase the thickness. Also pre rafter system impregnated with an antiseptic solution.

Mineral wool is laid in the gaps between the rafters on the crate and covered with a film for vapor barrier. The vapor barrier film is overlapped on the truss system. The width of the overlap of the web is visible on the film - a line is drawn along the edge of the web. The joints of the film are insulated with special glue and adhesive tape.

Floor insulation with expanded clay

Expanded clay should be laid on the floor of the attic on roofing material. The thickness of the expanded clay layer is determined by the thermal conductivity of the floor, but in any case, the thickness of the expanded clay should be at least 15 cm, and preferably 20-25 cm.

It is known that up to 15% of the heat from the house can go through the ceiling. Therefore, to reduce heat losses, the ceiling is insulated with expanded clay and other materials. Expanded clay not only retains heat, but also increases sound insulation.

Expanded clay is usually used to insulate concrete floors. To do this, it is covered with a layer of 200-250 mm, poured on top with a cement screed up to 50 mm thick. The screed will serve as the floor.

The cement-sand mortar for the screed must be of a dense consistency so that it does not flow into the expanded clay backfill.

Warming with mineral wool

Mineral wool should be laid from the farthest point of the attic.
You need to cut the insulation on a hard surface.
Beams, pipes, ventilation shafts, etc. should be covered with insulation.
Mineral wool should be laid in a layer of at least 25 cm.

When working with mineral wool, personal protective equipment is required. These are goggles, rubber gloves, a respirator and long sleeves. Do not work near open food and drinking water. Contact with mineral wool on the skin causes irritation and itching.

Insulation with polyurethane foam

Insulation of the attic with polyurethane foam is carried out by spraying on partitions, roofs, gables and attic floors, so the thermal insulation layer is obtained without seams and joints, that is, a monolithic vapor-tight layer is obtained.

Polyurethane foam has a low coefficient of thermal conductivity, so the thickness of the polyurethane foam layer is several times smaller than the mineral wool or foam plastic layer.

The use of polyurethane foam increases the usable area of the attic space.

An attic insulated with a sprayed layer of polyurethane foam is not affected by moisture, condensation does not form on the walls, because polyurethane foam keeps warm air inside. Moisture does not pass through polyurethane foam and cannot settle on a cold roof.

Floor insulation with sawdust is used only in non-residential attics, since sawdust will gradually compact when walking, which will lead to cracks in the concrete screed. The most common solution recipe using sawdust to insulate the attic floor:

Ten buckets of small sawdust.
One bucket of cement, at least 300 grades.
One bucket of fluffy lime.
Ten liters of water with antiseptic. It could be boric acid, blue vitriol, laundry soap.

The volume of water varies depending on the moisture content of the sawdust. The finished solution of sawdust is laid in layers of 20-25 cm thick and rammed. All building materials that are used in the walls of the house must be vapor-permeable. That is, it is impossible to use roofing material, polyethylene, roofing felt and other materials that do not allow moisture to pass through.

From above, a layer of sawdust during insulation is closed with shields made of plywood, fiberboard or boards. The thickness of the layer of sawdust on the walls should be at least 15 cm, on the ceilings and on the floor - at least 25 cm. When insulating the floor, sawdust is made on top cement strainer 5-10 cm thick.

To reduce heat loss in a private house, one effective heating system is not enough - to minimize them, it is necessary to insulate all elements of the building. The same applies to the roof. If it is not planned to equip the attic, insulation of the cold attic floor will be required.

A bit from the history of roofing

Since ancient times, people have built private households with such high quality that they could stand for 100 years. At the same time, it was not cold to live in them, and the natural wood roof frame was always dry. As for the shape of the roofs on such buildings, they were most often built with two slopes, and had a slight slope.

This choice was explained by the fact that the snow that fell in winter had to linger on the roof and act as a natural insulation. In the attic of the building, one, less often two windows were made. They were closed for the winter and then the air in the under-roof space played the role of a heat insulator.

During the summer, the windows were opened slightly at night to cool the temperature in the attic. In the heat they were closed, and the air did not heat up. So in the attic they regulated the temperature.

In winter, when snow fell, it covered the roof with a continuous carpet and thus was a roofing natural heat insulator. Even in severe frosts, the temperature in the under-roof space did not drop below zero. As a result, the house was warm in cold weather.

At the same time, the roof slopes were not insulated so that the snow on them would not melt. The rafter system was left open, thereby allowing its inspection and maintenance. Therefore, in such attics, only floors were thermally insulated.

If the roof slopes are insulated, then the attic becomes a heated attic, which has a different functional purpose.

Building materials for floor insulation - the better to insulate

A large selection of building materials is presented on the domestic market. To decide how to insulate the ceiling of a cold attic, it is necessary to take into account the conditions in which the heat insulator will be operated.

There are a number of requirements for a heater:

preservation of its original qualities at temperatures from -30 to +30 degrees;
in hot weather, the material should not emit substances harmful to people and freeze in severe frost;
you need to choose a fire-resistant heat insulator if lighting is planned in the attic;
products must be moisture resistant so that when wet, their original properties do not decrease.

Before you purchase materials for insulating the floor of an unheated attic in a private household, you need to consider what the floor is made of. If these are wooden beams, then bulk, roll or slab heaters are used. When the ceiling was created from concrete slabs, bulk or slab insulators that are heavy in weight can be used. Often a cement screed is poured on the floor.

In the form of plates and mats they sell:

mineral wool;
extruded polystyrene foam;
Styrofoam;
straw;
seaweed.

In the form of rolls are made:

mineral wool;
stone and glass wool;
algae ladders.

One of the most popular options for arranging thermal insulation is the insulation of the attic floor with mineral wool.

Bulk materials include:

expanded clay;
sawdust;
straw;
reeds;
ecowool;
granular foam;
slag.

When is insulation installed in the attic? wooden house, you need to use natural, environmentally friendly and breathable materials.

Mineral wool attic insulation

This modern and popular insulation is produced in rolls or mats. Mineral wool does not burn, does not rot, various microorganisms and rodents are not dangerous to it.

Insulation of the attic floor with mineral wool is carried out in stages:

First lay the lining material on the floor. In the case of an economy option, inexpensive glassine is laid on the floor. A more expensive and high-quality device will be a flooring device made of a vapor barrier film, which is mounted with an overlap.
At the same time, the joints of the segments are glued with adhesive tape or fastened with wooden slats, fixing them with a stapler.
The width of the thermal insulation material is selected taking into account the technical standards for a particular region. The mineral wool between the lags is laid out tightly, leaving no gaps. Tape is used to seal the joints.
After the installation of the insulation is completed, even boards are placed on the logs and this is how the floor in the attic is formed.

The above solution on how to insulate the attic of a private house with mineral wool gives the material the ability to "breathe" and ventilate when moisture gets on it. To prevent the penetration of moist air into the insulation, waterproofing is mounted under the roof.

When working with mineral wool, you need to use protective equipment, such as a respirator, goggles, gloves and overalls.

Application of extruded polystyrene foam

Styrofoam (expanded polystyrene) refers to loose materials, so it is used if it is necessary to insulate a floor made of logs and beams. For thermal insulation of plates, extruded polystyrene foam is used, which is denser than conventional foam.

Before laying it, the surface of the base is leveled. On the warm side of the floor, vapor barrier is not needed, since concrete slabs have practically no vapor permeability. A vapor barrier film is laid out on the prepared base. Then, slabs of extruded insulation are laid out in a checkerboard pattern. Mounting foam is blown into the joints.

After it dries and becomes hard, the thermal insulation boards are poured concrete mix about 4-6 cm thick. After hardening, the screed becomes suitable for use as an attic floor. If desired, you can lay the final coating on the screed.

Insulation of a cold attic with ecowool

Ecowool is a lightweight and at the same time friable heat insulator, consisting of cellulose, it also contains flame retardants, such as boric acid and borax. Before starting work, a film is laid on the floor. For laying ecowool, a special blowing machine is used.

The heat-insulating layer is applied continuously, without leaving even the slightest gaps. Ecowool contains a large volume of air, so a layer of 250-300 millimeters is enough. When performing insulation, it should be remembered that shrinkage of this material occurs over time. Therefore, a layer of ecowool is applied with a margin of 40-50 millimeters.

Then the insulation must be moistened with water or with a solution. It is prepared from 200 grams of PVA glue and a bucket of water. The broom is moistened in the solution and the cotton wool is well moistened. After drying, lignin is formed on the heat-insulating layer - a crust that prevents the insulation from moving.

Which method of attic insulation from the above options to choose depends on the specific situation.

As many remember from school course physics, the warm air in the room rises, and the cold air, respectively, falls. It is through an uninsulated attic and roof that a house loses from 15 to 30% of its heat! Usually the attic is insulated during the construction of the house, but if necessary, attic insulation can also be done in a private old house.

Roof insulation

Insulating the attic of a new house

As a rule, they begin to insulate the attic after the work on the arrangement of the roof is completed: the coating is laid, the wind insulation is made. First, the floor is insulated, and if the layer of thermal insulation material is sufficiently reliable, you can take your time with the insulation of the roof slopes and gables.

Keep in mind that for attic insulation wooden house you can proceed only after the building shrinks. Usually this is done no earlier than six months after the completion of construction, although shrinkage can continue for more than a year. Sometimes when shrinking wooden structures warp or cracks appear in them. Before starting work in the attic, these shortcomings should be eliminated.

For work you will need

Insulation (chipboard, mineral wool, expanded polystyrene, polyurethane foam, expanded clay, sawdust with clay, etc.).
Materials for arranging steam and heat insulation:
- vapor barrier foil (polypropylene or polyethylene film, metallized membrane or fiberglass membrane);
- one- or two-sided adhesive tape for sealing seams between sheets of foil;
- felt or polyurethane electrical tapes for heat and sound insulation of floors.
Tool for cutting insulation (mineral wool, expanded polystyrene boards) and finishing materials(chipboard, lining, drywall, etc.).
Boards, plywood, lining or drywall boards.
Nails, hammer.
Construction stapler and staples.
Protective goggles, respirator and gloves for working with mineral wool.

Keep in mind that the attic insulation methods listed below are used in cases where it is not heated and is used as a warehouse, summer workshop, etc. However, if the attic is heated or used as a summer residential attic, slopes and walls should be additionally sheathed with moisture-resistant drywall slabs and paint, and lay slabs of expanded polystyrene or chipboard on the floor.

We warm the space under the roof

Many people probably noticed that in old village houses only the floor of the attic is often insulated, but not the roof. The fact is that the inclined surface gable roof it holds a layer of snow well - it is it that serves as an additional “blanket” for the roof. Even in severe frosts, the temperature under the slopes rarely drops below zero degrees. In the attic, small windows are made that open for ventilation even in the summer heat.

In the attic, which will be used as a utility room, the space under the roof will have to be insulated. For self-insulation it is convenient to use sheet insulation (polystyrene foam, mineral wool mats) or rolled mineral wool. Density of mineral wool insulation - 10-55 kg / sq. m. Sometimes these heaters are also used together: polystyrene foam is attached with the first layer, mineral wool is the second.

Before fixing the insulation between the rafters, a vapor barrier foil is nailed to the crate with a construction stapler. The joints are sealed with insulating tape, but you can also overlap the foil. You can also use foil mineral wool mats. In this case, additional vapor barrier is not required.

Usually the required thickness of the insulation sheets is somewhat greater than the thickness rafter legs. Make thickening “packings” on them and nail perpendicular elements from wooden or steel slats. Between them, place an additional layer of insulation, after which it is fixed with thin slats, and fill the wooden covering on top. In residential attics, you can finish the finish with drywall.

We warm the floor

As in the previous case, before laying out the insulation, a vapor barrier is made (for example, from foil polyisol). When arranging the floor slab, the film is laid on top of it, when the wooden floor is insulated, it is nailed with an overlapping stapler.

Concrete floor insulation. If a reinforced concrete slab serves as a ceiling, materials with a high density (> 160 kg / sq. M) are used to arrange thermal insulation. These are mineral wool or cork mats, extruded polystyrene foam, and expanded clay from bulk materials.
Thermal insulation of a wooden floor. insulation in wooden floors laid between the lags. Usually these are cotton wool insulation with a low density (< 50 кг/кв.м). Поверх утеплителя желательно настелить рубероид, а в качестве чистового пола уложить плиты ДСП.

Thermal insulation of the attic of an old house

Before starting work on warming the attic of an old house, carefully inspect it. Check for cracks in the rafters and gables, what is the safety of the ceiling. It is possible that some beams will have to be replaced, or it may be necessary to additionally insulate the roof. wooden details it is necessary to impregnate with special moisture and fire-resistant solutions and an antiseptic solution from fungus and pests.

It is also necessary to complete a series preparatory work. If the attic of the old house was previously insulated, and the insulation has not lost its properties, additional insulation materials can be laid on top of existing ones. For example, on top of a floor insulated with clay and sawdust, you can install a crate and lay mineral wool. Thus, “the initial level of the floor turns out to be “rough”.

Otherwise, the old insulation should be removed, and a new modern one with a higher set of operational properties should be laid on top of it. After additional insulation, a new finishing floor is laid.

Features of working with common heaters

Basic requirements for insulation materials:

relatively light weight (this is especially important in houses with wooden floors);
non-toxicity;
ease of processing;
fire resistance;
moisture resistance;
good heat and sound insulating properties.

All these requirements are met to some extent by modern insulating materials. The most popular of them are polyurethane foam, expanded polystyrene, mineral (fiberglass and basalt) wool. In brick and stone houses with solid reinforced concrete floors, insulation is sometimes used "the old fashioned way". This can be done using inexpensive environmentally friendly expanded clay or clay mixed with sawdust.

Mineral wool

Insulation of the attic with mineral wool is the most inexpensive and at the same time acceptable in quality way of insulating attic spaces. Mineral wool has excellent heat and noise insulation properties, and its elasticity makes it easy to mount it on rafters. In addition, it is non-flammable and not susceptible to biological pests. Mineral wool is sold in the form of mats or in rolls.

Warming with mineral wool

Mineral wool slabs with so-called "randomly oriented fibers" are considered the most effective heat insulator. A mineral wool board with a thickness of only half a centimeter in terms of thermal protective properties replaces almost a meter brickwork! At the same time, it is quite light and does not create additional load on the floors. Mineral wool is a durable material, its service life is at least 50 years.

When working with mineral wool, you need to remember that it contains a certain amount of formaldehyde. In addition, the smallest mineral wool “needles” are dangerous for the eyes and respiratory organs and irritate the skin of the hands. Therefore, it is necessary to cut and, moreover, lay mineral wool in goggles, a respirator and gloves. Respiratory masks can also be used.

Polyurethane foam (PPU)

Polyurethane foam refers to a liquid heat insulator and is applied to any surface (wooden, brick, stone, concrete) by spraying. Today it is considered the most effective heat-insulating building material. When processed with polyurethane foam, a durable base coating is created, so there will never be drafts in the insulated attic.

Insulation with polyurethane foam

By itself, polyurethane foam is an expensive material. However, before applying it, you do not need to do vapor barrier and waterproofing, and working with it is much easier than with other heat insulators. They can process the space under the roof between the rafters, and the voids between the logs of the wooden floor, and reinforced concrete floors.

Polyurethane foam allows you to reduce heat loss by almost almost 30% (compared to other materials for thermal insulation). Having spent a large amount of money on its purchase, in winter you will save twice on heating.

Styrofoam

Inexpensive, lightweight and durable, extruded polystyrene foam sheets are commonly used in old houses with hardwood floors. It holds heat well and does not weigh down the supporting structures, it is easy to cut (with a sharp clerical knife or saw) and mount it. Its other advantages are moisture resistance (it does not absorb moisture) and environmental friendliness.

To insulate the space under the roof and the floor, plates with a thickness of 10-15 centimeters are used in two layers. The first is fixed between the lags, and the second is laid on top of them. They fix the structure with slats, lay a vapor barrier on top (for example, Izospan), and then upholster it with plywood or clapboard.

It is worth insulating the attic with polystyrene foam if you use it as a technical or utility room. But if you are going to arrange, for example, a workshop in the attic, it is not recommended to use it. This material offers little to no noise protection and is not resistant to organic solvents that can spill onto the floor or evaporate into the air. Some types of expanded polystyrene are resistant to fire, but in general it is considered a combustible material.

Expanded clay

Expanded clay is an inexpensive and quite effective natural heat-insulating material, which is used for thermal insulation of foundations and floors. It can be used in attics with reinforced concrete floors, as it creates a significant load on the beams. Effective Layer expanded clay on the area 100 square meters according to GOST, it is poured with a layer of up to 60 centimeters, while the weight of the bedding is about 30 tons! In non-residential attics, the insulation layer may be smaller (25-40 centimeters), and in this case they do not make a concrete screed, but it often turns out to be unbearable for the attic floor of a wooden house.

Expanded clay insulation

Attic insulation with expanded clay has some features compared to other materials. Since this is a porous material that absorbs moisture, not only vapor barrier, but also waterproofing must be laid under the expanded clay backfill. It can be a roofing felt or an ordinary plastic film, which is better to lay with a single sheet, and not welded from several sheets.

It is not recommended to use polyethylene for a wooden floor, since the tree covered with it will not "breathe" - it is preferable to use Izospan as a vapor barrier.

For insulation, expanded clay of a fraction of 10-15 mm is used, which is poured into wooden frame("box"), made around the perimeter of the room. A vapor barrier membrane is also laid on top of the expanded clay layer. Despite the good thermal insulation properties of expanded clay, experts do not recommend using it specifically for thermal insulation of attics. If the attic is already insulated with expanded clay, its layer is insufficient, but you have no way to completely change the insulation, remove the subfloor and lay mineral wool on the expanded clay (under the upper vapor barrier membrane).

sawdust and clay

In the days of our grandmothers, in order to “do not blow from above”, dry leaves, straw, and hay were laid on the attic floor. But the most common and affordable way to make the house cozy was to insulate the attic with sawdust and clay. Insulate the attic country house or at wooden dacha the old fashioned way is very simple. It is important that this method of insulation will cost you almost free.

Insulation with sawdust and clay

Prepare the solution:

dilute the clay to the density of fatty milk;
Pour enough sawdust into the solution so that the solution can be mixed. In appearance, it will be just wet sawdust, slightly smeared with clay;
pour the mixture on the attic floor with a layer of 15 centimeters, level and tamp.

After the mixture dries, it will turn out very dense, slightly springy. flooring. From above, you can add another five centimeters of wet sawdust and tamp again. A mixture of clay and sawdust keeps heat well, besides, such a floor “breathes”. Fill the floor with a thin layer of lime, and sprinkle straw, chaff or dry sawdust on top.

If you are finishing building a house, almost finishing work has already been done and you don’t know whether to take on the attic or whether this business can wait, and in general what is needed at this stage, this article will help you. Here we will consider the insulation of the attic floor with materials different type, with step-by-step illustrations, expert advice and a helpful video.

We will also reveal many important points why insulation is so necessary and what the attic floor pie should actually be like on wooden beams and on a reinforced concrete slab - step by step.

What insulation is suitable for the attic?

It is necessary to insulate the attic floor when the attic space is not planned to be used for housing. Those. we are talking about a cold attic, the roof slopes of which are not insulated at all. And far from all the same materials are already suitable for overlapping, they are selected for slopes.

Mineral wool: no harmful dust

So, when insulating the attic floor with mineral wool, it is correct to use the so-called tension method. Its essence is that first the insulating material is laid - and so that it registers between the beams.

After that, a slab or rolled mineral wool insulation with a total thickness of about 150 millimeters is laid on it in three layers, and it is covered with a vapor barrier film on top. After that, plywood, which should be no thinner than 18 millimeters.

Expanded polystyrene and foam: ease of installation

High-quality insulation of the attic floor with expanded polystyrene is also obtained, the main advantage of which is that there is no need for vapor barrier, and all gaps are easily sealed with mounting foam.

Inflatable insulation: fashion and rationality

Recently, it has become especially popular to insulate the attic floor by blowing.

The main advantage of blown insulation is that it fills all the voids that exist by itself and creates an even continuous layer. In which there are no joints, no seams and no adjoining, and for which there is no need to cut separate small pieces of prickly insulation to plug something.

Today, for the insulation of cold attics in Russia, two types of blown insulation are mainly used: ecowool and blown wool.

Ecowool up to 80% consists of cellulose fibers, which are produced from ordinary waste paper, and 20% from additives such as snowstorm as a fire retardant and boric acid as an antiseptic. Such a heater has a high thermal conductivity.

But blown wool is obtained by grinding ordinary mineral materials for thermal insulation, which for some reason did not pass the product acceptance.

For example, they did not have sufficient density or the correct structure of the fibers. And such material is crushed and packed under high pressure, and therefore it is easy to transport it to the site of the facility, where everything will be loosened again upon arrival.

But still, ecowool is most often used as a material. The insulation itself in the process looks like this: one person must remain near the installation and monitor its normal operation, while loading the material. And the second person goes up to the attic with the hose, makes a cruciform incision on the vapor barrier (just between the beams), inserts the hose into this incision, and fills the cavity with material.

Plus, relatively inexpensive bulk materials are used to insulate a cold attic:

What parameters of the heater should be paid attention to?

In no case do we urge you to purchase the most expensive heat-insulating materials to insulate your attic floor. But note that the more and longer any well-known company produces materials for this purpose, the more it pays attention to quality, changing their bulk density, improving their products and increasing thermal insulation coefficients. And that already says something.

For the rest, always pay attention to such parameters of heaters that are important for a wooden floor, and have none for concrete - and vice versa.

Parameter number 1. Biostability

We are talking about the fact that in such a heater, which often remains open, bugs or some other living creatures do not start. This is especially true of mice, who love to live in a warm and dry (and, most importantly, deserted) attic.

Another important requirement for attic insulation is water resistance. Raindrops accidentally falling into it or simply moisture should not lead to the process of decay.

Glass wool is recognized as one of the most resistant heaters:

Parameter number 2. Thermal conductivity

The main requirements for insulation for the attic floor is the ability to maintain thermal insulation properties for a long time.

When buying a heater, also pay attention to such an interesting point: modern manufacturers thermal insulation materials always point to technical specification three coefficients of thermal conductivity of the material at once: in a dry state, at a temperature of 10 ° and 25 °, and humidity categories A and B.

You need to look at the coefficient of thermal conductivity in a dry state, or at a temperature of 10 degrees, because this is exactly the normal climatic situation in the attic. For a more accurate and detailed thermal calculation, you will need a SNiP table.

Now let's take a moment. When choosing a heater, you will probably be advised to take a heater with the lowest possible degree of thermal conductivity. But in fact, this only makes sense for residential attics, because when you have to insulate the roof slopes, then too thick materials cannot be laid between the rafters. Therefore, materials are needed here that will conduct heat as poorly as possible, but at the same time have a small thickness.

But for the attic floor, just the thickness of the insulation is not a critical factor, and you can save on this. Just take a cheaper insulation, but thicker, albeit with high thermal conductivity. You are all compensated by the height of the insulation itself.

Parameter number 3. Weight

Depending on the chemical composition, each heater has its own bulk density. So, materials such as basalt, glass and any other inorganic and organic compounds are most often used as the basis for fibers. From their type, the heat-insulating material itself becomes either light or heavy. And the shape of all these materials is provided precisely by the elasticity of the fibers: how much they straighten between the floor beams.

Note that heavy insulation keeps its shape better due to the rigidity of its fibers. And foam insulation has the best stability for attic floor insulation, which in this parameter is equated to hard stone wool. But there is a moment: the same mineral wool insulation that was inserted between the floor beams can be easily straightened and pressed tightly against the wood, but the foam one will not do this, and voids form - the bridges are cold. Therefore, you will have to additionally use a can of foam to close all the cracks.

On the other hand, if the attic floor is insulated on a reinforced concrete slab with foam-based materials, then there will only be pluses. Not to mention the fact that the attic concrete floor itself already has a considerable weight and creates a serious load on the walls and foundation of the house, and the use of light insulation for it is only a big bonus.

And unlike the concrete floor, the attic floor is able to withstand a fairly limited load. Therefore, the weight of the insulation in this regard is also not the last moment. After all, there are already many variations here: the same cubic meter of thermal insulation can weigh as much as 11 kilograms, and all 350 - this is the norm.

One of the heaviest heaters is basalt wool:

Parameter number 4. Moisture resistance

Rain moisture or roof leaks accidentally getting into the insulation should not start the rotting process. It is bad if after six months or a year the new insulation begins to decompose from the inside, while emitting an unpleasant smell of dampness.

Therefore, attic floor insulation on wooden beams and on concrete is quite often done using polystyrene foam or polystyrene foam, which are known for their almost zero hydrophobicity.

Parameter number 5. Environmental friendliness

Another point: the attic insulation should not emit any toxic and pungent substances in terms of smell, despite the fact that, perhaps, no one will walk in such an attic.

It's all about ventilation: sooner or later, the insulation molecules are picked up by the air and brought into the living quarters, which can be unsafe for the residents of the house. Therefore, choose a heater that meets sanitary standards.

Parameter number 6. Shape saving

Another important point- this is the form of stability of the selected insulation. So, special laboratory tests have shown that over time, heat loss through the gaps between the plates or the matte heat insulator can reach 40%. And this despite the fact that the material itself during the same time may not change its thermal conductivity at all, if at the same time it remained dry.

Therefore, the stability of the shape and dimensions of the material over time is very important. For the concrete floor of the attic, such gaps will not be critical, because here the floor itself is quite heat-insulating, which cannot be said about the attic floor.

But the problem is that in the technical information for modern heat insulators such a parameter as shape or stability cannot be found.

Parameter number 7. Fire safety

And the last point: attic insulation must meet all fire safety requirements. Take the same popular ecowool, which is not just made from ordinary waste paper and pieces of newspapers. It would seem that everything is simple and ingenious, why don't you cut the paper into smaller pieces too, and just fill the attic with it? Would it be worse? After all, the principle of friability is also involved here, like in animal hair, when air molecules get stuck between small elements.

Let's just say: yes, the insulating properties of this method will not be worse, but it is the old dry paper and wood that most often leads to an unexpected fire. That is why modern cellulose insulation is necessarily treated with special chemicals against fire.

If we are talking about the combustibility of materials, then it is important that the insulation not only does not burn, but also has attenuation. Just remember that everything is burning at the epicenter of the fire, both iron and concrete, but if attic floor a spark falls, then the heater should not light up. That's what it's all about.

This is what the attic insulation cake itself should look like:

Vapor barrier questions: how, on which side and is it necessary?

For the insulation of roofing made of wood and concrete, the vapor permeability of the insulation is of great importance. So, all heaters that are made today in the form of plates and rolls can be conditionally divided into "wool" and "foam", as building contractors like to do.

To "cotton" we will refer heat-insulating materials made of organic and mineral fibers - this is mineral wool, stone wool and glass wool insulation. All these materials are formed by the hardening of plastic masses of very different chemical origins. And all these materials have approximately the same coefficient of thermal conductivity: within 0.04.

All these materials are made up of fibers that are intertwined with each other. They do not form any closed pores, and water vapor easily enters and escapes through them. Therefore, all wadded heaters are vapor-permeable materials. Why, under production conditions, their fibers are additionally coated with a special water-repellent substance, and the heaters also turn out to be hydrophobized: a water molecule from water vapor is not allowed to penetrate and wet the insulation. It can only cling to its surface, and when a critical mass accumulates, it transforms into drops and rolls down. It turns out that hydrophobized cotton wool insulation is not a wet vapor-permeable material.

Therefore, until now, scientists from all over the world cannot come to an unambiguous conclusion: vapor permeability building insulation- Is this good or bad. Let's just say that if you equip the attic floor on wooden beams, you'd better lay vapor-permeable materials on it so that the wooden rafters, which have taken on moisture from the lower living quarters (and water vapor always rises), can freely give it to the insulation . And they will easily come out of the insulation - through ventilation alone is enough. But in terms of floor insulation on concrete, there is not much difference. But there is such a moment here: when using vapor-permeable heaters, it is important that the ventilation of such an attic is organized in accordance with all the rules, and a separate ventilation system will not interfere.

Note that there are no fibers in foam insulation, since such material is literally made from air. All foam insulation consists of a cellular structure, with closed bubbles and not closed, like a kitchen sponge. Therefore, such heat insulators can be both vapor-permeable and non-vapor-permeable. For example, extruded polystyrene foam, which is better known to us as polystyrene, passes water vapor between the balls, but extruded polystyrene foam does not.

Interestingly, you can use not only one type of insulation, but two at once to compensate for each other's shortcomings. But at the same time, a heat-insulating material with a lower vapor permeability must necessarily lie in front of a heater with a high vapor permeability. That is, first polystyrene foam, then cotton wool. Otherwise, in the opposite case, a material with a lower vapor permeability will become a certain vapor barrier for another material, it will simply begin to rot and there will be nowhere for moisture to go.

How to insulate a concrete attic floor

If we are talking about the insulation of the attic floor of concrete, then the thermal insulation must necessarily be in the form of two or three layers with overlapping joints of each lower layer. Moreover, it is very important that the entire surface be leveled so that there are no irregularities of more than 5 millimeters anywhere - this is not difficult to achieve with modern leveling compounds.

For concrete attic floors, extruded polystyrene foam slabs are ideal as thermal insulation. They don't need a vapor barrier, but if you put styrofoam - it's not extruded polystyrene foam, and then, of course, you need it.

Additionally, if you later need to walk on such a floor, you can make a cement-sand screed up to 4 centimeters and put two layers of drywall sheets. Just be sure to make masonry mesh paths for such a screed that you will walk along. Be sure to glue the joints between the foam polystyrene plates with tape so that cement milk does not leak between the plates.

The attic floor itself can be insulated both at the manufacturing stage and at almost any time during the operation of the house itself. Of course, for the attic it is much more correct to insulate the floor even before you move into your new home.

More details about the process itself:

How to insulate a wooden attic floor

So, there are two main ways to insulate the attic floor: laying a heat-insulating layer inside the structure of the attic floor, and laying insulation on top of it. For a cold and non-residential attic, it is not necessary to cover the insulation with something on top and build a full-fledged floor. But then be sure to leave the running ladders - separate paths from the sparse flooring throughout the attic area, this is necessary for roof maintenance.

Under the insulation, you need to put a vapor barrier, and in the form of a trough, so that it can protect the insulation from water vapor, which comes from the lower living quarters. But there is an exception to this rule: if the insulation was laid with good resistance, for example, it is foam or extruded polystyrene foam, then vapor barrier is not needed here. But if we are talking about an attic with a particularly wet regime, for example, above a kitchen or a sauna, then a vapor barrier layer must be installed here.

Another method is tension, when the vapor barrier only sags slightly between the beams. The disadvantage of this method is that in this way the insulation between the beams is not inserted tightly enough.

And if the overlap is also made from ready-made companies, then this option is not suitable at all, because such voids quickly become the so-called cold bridges. Therefore, in Russia the method is more popular, in which the insulation is first laid, then it is covered with a vapor barrier, and only then - with a finishing floor.

So, this is what the whole process of warming looks like:

Step 1. A vapor barrier is fixed between the beams using a construction stapler.
Step 2. Next, mineral wool slabs are cut so that their width is corresponding to the step of the beams.
Step 3. These plates are carefully inserted into the gap between the beams.
Step 4. For a while, while the ceiling is not yet ready below, so that the insulation does not fall between the beams, it is supported by draft bars or a strong thread stretched especially for this.
Step 5. Next, a diffuse membrane is quickly mounted on top of the insulation - so that steam can easily escape through it, and drops from above from the slopes do not penetrate inside.

But let us also note such a moment about the last step. Many experts believe that no diffuse membranes or windproof films are needed for insulation, because in a cold attic, thermal insulation will dry due to natural ventilation of convection air flows that easily penetrate through holes and dormer windows.

How to leave running ladders in a heater

If you use soft thermal insulation materials to insulate the attic floor, you need to make running ladders above them - but only so that cold bridges do not turn out. Therefore, it is better to take either rigid materials, or insert the legs of the ladders directly into the insulation.

That's all the tricks of warming the attic floor of various types!

Warming the attic floor of the house allows you to save more heat inside the room, and not spend it on heating a cold attic. Well, if it is used as a utility room (technical attic) or as an attic, but if not? Then it is pointless to spend resources on heating an unheated attic space.

That is why it is worth making the insulation of the cold attic ceiling using heat-insulating materials. You can perform insulation from the side of the attic or from the side of the room (inside / outside). It is best to do this during the construction period of the building, or immediately before the final finishing of the room. But even during the operation of the house, there is no reason not to insulate the ceiling from the attic.

The thickness of the attic floor insulation is standardized using SNiP II-3-79 "Construction Heat Engineering". This manual contains detailed recommendations on the choice and formulas for calculating the resistance to heat transfer of various thermal insulation materials. The calculations take into account not only the type of material, but also the average annual temperature, the duration of the heating season, wall material Houses.

The attic floor insulation technology depends on the material chosen.

In this article we will consider the most popular heaters.

Mineral wool is a heater, the fibers of which are arranged in a certain way. Namely, this randomness leads to the fact that an air cushion is formed between the fibers, which informs the insulation of its properties. However, the same feature of cotton wool increases the ability to absorb moisture. To avoid this, you need to know how to properly install mineral wool.

Benefits of mineral wool:

high density;
long service life;
Fire safety;
ease of installation;
the use of mineral wool for insulation of horizontal surfaces does not lead to its caking, slipping and, as a result, the formation of cold bridges.

Among the disadvantages: the ability to absorb moisture.

There are three main ways to lay cotton wool: continuous, in grooves or in cells (see photo). The choice of method depends on what load will fall on the floor in the future. The most stable frame is obtained in the latter case.

First stage

It starts with laying the vapor barrier film. The film will allow you to remove the steam that rises from a warm living space to a cold attic. To lay the film correctly, you need to carefully read the markings applied to it. Be sure to observe an overlap of 100 mm.

If insulation is made on wooden beams, then the film must go around all the protruding elements. Otherwise, the beams may rot.

At the junction of the film and walls or other protruding surfaces, it is necessary to raise it to a height equal to the thickness of the insulation plus 50 mm. and glue it with tape or wrap it on the insulation plate.

Second phase

Insulation (wool) is being laid. This is a fairly simple process. Slabs or strips are easily cut with a construction knife to the desired size.

When laying the sheet, make sure that there are no gaps left or that the mineral wool material is not strongly squeezed. Both will lead to a decrease in the quality of insulation. Common Mistakes on the picture.

a) insufficient thickness of the heat-insulating material;

b, c, d) the thickness of the attic floor insulation is incorrectly selected.

insulation with foil will increase the resistance of the material to heat loss. The sheet is laid with the foil side down.

the insulation should not protrude beyond the beam. If such a situation exists, the beam needs to be lengthened wooden beam or additional lath up to the thickness of the insulation.

a thin insulation laid in two layers retains more heat than one thick one. In this case, the plates must be laid in a checkerboard pattern.

if there are protruding structural elements in the attic, for example, a chimney pipe, you need to raise the insulation to a height of 400-500 mm. and fix it.

Third stage

Waterproofing is carried out if the attic is not supposed to be used, and the truss system is not protected by a waterproofing film. If roofing material separated from the attic with a film, then you can proceed with the final stage.

Draft floor. It is laid over the insulation and serves as the basis for the final finish.

The process according to the installation technology is similar to the insulation of the attic floor with polystyrene foam.

The advantages of these materials:

low cost;
ease of operation;
waterproof.

Among the disadvantages: flammability.

Attic floor insulation technology with polystyrene foam or polystyrene foam

The process of installing rigid insulation based on is more than simple and can be done by hand. The work can be divided into two stages:

surface leveling. To ensure high-quality insulation, there should be no significant irregularities on the floor of the base. You can eliminate such differences by performing a screed with a sand-cement mortar.

slabs are laid butt-to-butt or between beams. The presence of a bar increases the strength of the floor.

Tip: carefully seal any seams, incl. joints with beams. Bypassing the obstacle, try to cut holes as accurately as possible. A homogeneous thermal insulation layer retains heat better.

Rough coating

Styrofoam must be protected from destruction with a film in a non-residential attic. In a frequently used or residential attic, you need to somehow move, so it is better to equip a subfloor from OSB or a sand-cement screed over polystyrene foam or polystyrene foam.

Sawdust is finely chopped wood.

Advantages:

naturalness;
no toxic impurities;
light weight;
material availability.

The disadvantage is flammability.

Attic insulation technology with sawdust

before proceeding with the insulation with sawdust, they need to be prepared. Namely, mix cement and water with sawdust in a ratio of 10:1:1.

Pour the attic floor with the finished mixture and level it. It is worth noting that it is possible to use sawdust as a heater without using a frame only in a non-residential attic. Otherwise, when walking on the floor, sawdust will be compressed, and the concrete screed will collapse.

build a cellular structure from a bar. Pour a solution with sawdust into each cell. The advantage of this method is that a subfloor can be laid along the timber. And the attic will be usable

Expanded clay is obtained by firing clay.

Advantages:

low thermal conductivity;
naturalness;
environmental friendliness;
ease;
availability.

The disadvantage is associated with the difficulty of lifting expanded clay to the height of the attic.

Expanded clay is usually used if it is necessary to insulate the attic floor over the slabs.

Expanded clay attic insulation technology

The work is carried out in three stages:

the plate is inspected for cracks and cracks. They are sealed with mortar or covered with thick paper. The protruding elements do not create difficulties with backfilling of expanded clay.

mount a crate from a bar. A rough floor will be laid on it in the future.

loose insulation is poured onto the stove and leveled with a conventional rake. Layer thickness 250-300 mm. You can move around expanded clay without restrictions.

Tip: when filling expanded clay, it is better to combine granules of different sizes (diameters). This way you can avoid the appearance of voids.

At the end, a subfloor is mounted or poured with a sand-cement screed.

Please note that the insulation of the attic wooden floor has some nuances:

the tree is subject to decay, which means that the steam rising up must pass freely. Improper installation of films or the use of non-breathable materials, such as roofing felt, will lead to the destruction of wood in the future.

using foil insulation, you need to place it with the foil down. So the wood will be protected from water ingress and at the same time, it will not accumulate steam moisture.

"Correct" - use a superdiffusion membrane or vapor barrier film

"Wrong" - to lay a special film without taking into account the marking or in general a regular film

The scheme of insulation of the attic floor for heaters of various types is given below.

Conclusion

In this article, we focused on the main stages and features of warming the attic floors of a private house using heaters various kinds. We hope that this information will be useful to you.