How to insulate the roof of a house attic. Insulation of the attic floor in a private house is an effective way to keep warm. Insulation of the attic floor with foam

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

A little 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, living in them was not cold, and the roof frame made of natural wood was always dry. As for the shape of the roofs on such buildings, they were most often erected 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 serve as a natural insulation. In the attic of the building, one, rarely 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.

IN summer period the windows were slightly opened at night so that the temperature in the attic would drop. In the heat, they were closed, and the air did not heat up. This was how the temperature was regulated in the attic.

In winter, when the snow fell, it covered the roof with a solid carpet and thus was a natural roofing 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, thus allowing for inspection and maintenance. Therefore, in such attics, only floors were 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, one must take into account the conditions in which the heat insulator will be used.

A number of requirements are imposed on the insulation:

preservation of their 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 purchasing materials for insulating the floor of an unheated attic in a private household, you need to consider what the overlap is made of. If this wooden beams, then they use bulk, roll or slab insulation. When the slab was made of concrete slabs, bulk or slab insulators, heavy in weight, can be used. Often, a cement screed is poured onto the floor.

In the form of slabs 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 insulation of the attic floor with mineral wool.

Bulk materials include:

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

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

Insulation of the attic floor with mineral wool

This modern and demanded insulation is produced in rolls or mats. Minvata does not burn, does not give in to decay, various microorganisms and rodents are not dangerous to it.

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

First, the lining is laid on the floor. In the case of an economy option, an 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 tape or fastened wooden slatsfixing them with a stapler.
The width of the insulating material is selected taking into account the technical standards for a particular region. Mineral wool between the lags is laid out tightly, leaving no gaps. Scotch tape is used to glue the joints.
After completing the installation of the insulation, flat boards are placed on the logs and this is how the floor in the attic is formed.

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

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

Application of extruded polystyrene foam

Polyfoam (expanded polystyrene) refers to loose materials, therefore 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 on the prepared base. Then, plates of extruded insulation are laid out in a checkerboard pattern. Polyurethane foam is blown into the joints.

After it dries and becomes solid, the thermal insulation slabs are poured with a concrete mixture about 4-6 centimeters thick. After hardening, the screed becomes suitable for use as an attic floor. If desired, the final coating can be laid on the screed.

Insulation of a cold attic with ecowool

Ecowool is a lightweight and at the same time loose heat insulator, consisting of cellulose; it also contains flame-extinguishing agents, for example, 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 equal to 250-300 millimeters is sufficient. When performing insulation, it should be remembered that this material shrinks 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 a solution and the cotton wool is well moistened. After drying, lignin forms on the insulating layer - a crust that prevents the insulation from displacing.

Which way to isolate the attic from the above options to choose depends on the specific situation.

Insulation of the attic is an important part of the overall thermal insulation of a house.

It is necessary to approach the insulation of any structure in a comprehensive manner. All experts say so.

After all, support temperature regime in a house, regardless of its structural material, it is impossible at the proper level, having insulated only the walls in it.

Therefore, both the floor and the ceiling, especially the attic, are subject to thermal insulation. Question: "How to insulate an attic?" is very acute when it comes to a wooden, private building.

Everyone knows the law of physics, according to which warm air has a smaller specific gravity, therefore, it always rises up when cold air remains at the bottom. The same thing happens in the rooms of the premises. Warm air rises to their ceiling, cold air is closer to the floor. If thermal insulation is not carried out ceiling slab or attic space, then warm air freely penetrates through the structural material of the ceiling and gives it part of its energy. In a word, if you do not insulate the ceiling and attic of the house, then about 30% of all heat losses of the building pass through it.

Features of warming the attic of a wooden house

It is necessary to insulate the attic in a liquid house in order to avoid heat leakage.

To properly insulate the attic in wooden structure, you need to remember a few rules:

warm air always contains water impurities, that is, warm air in a room is always saturated with household steam. A tree, being constantly in an atmosphere of high humidity, can lose its specifications or just rot. Therefore, when carrying out thermal insulation of this structure, it is necessary to remember about the waterproofing layer;
the tree is able to let air through itself, that is, it "breathes". Air and steam in it can be on the surface and in the thickness of the insulation material, even if it is located outside the structure, therefore, an additional layer of waterproofing material is also needed here;
wood, in comparison with other structural materials of buildings (brick, metal structures), has a lower bearing capacity, because insulation material for wooden house should not put additional stress on the floor;
the thermal insulation material must have fire-fighting characteristics in order to prevent the spread of fire in a wooden building.

Mineral wool, glass wool

Mineral wool, glass wool - materials belong to environmentally friendly products, fire-resistant, lightweight, easy to install. However, it is distinguished by high rates of vapor permeability and water absorption, therefore, they require a waterproofing or vapor barrier.

Polyurethane foam

Technology of insulation of the attic of the house with polyurethane foam.

Polyurethane foam - obtained from gas-filled plastics, sold in the form of cylinders under pressure, applied by conventional spray to the desired surface. Advantage - forms a seamless coating, which prevents the formation of cold bridges, is distinguished by a high degree of adhesion in wooden surface, therefore, does not require additional fasteners. It is lightweight, therefore it does not exert additional pressure on the floor, it is distinguished by high rates of heat and sound insulation, and does not absorb moisture.

Polyurethane foam does not rot, firmly tolerates the action of an aggressive environment, microorganisms do not develop on its surface. It is characterized by strength and rigidity, it does not absorb water and does not let steam through itself. The disadvantage is the high price compared to similar products.

Expanded polystyrene

Expanded polystyrene - it is mistakenly called polystyrene foam. Expanded polystyrene, in contrast to polystyrene, undergoes several additional processing stages, therefore it is characterized by increased strength. Correctly organized on the basis of its insulation layer in the attic of a wooden house is vapor tight. Expanded polystyrene is moisture resistant, but it does not tolerate the action of organic solvents. It promotes the spread of fire.

How to properly insulate the attic - execution technique

If the attic of a wooden house is not planned to be converted into a living room, it is enough to simply insulate the floor. Insulation process stages:

You can properly insulate the attic of a private house with your own hands.

clean the surface of debris and rot, treat the floor with an antiseptic, if there are gaps, they must be additionally caulked;
the attic is covered with a waterproofing film, but it must let steam through, otherwise the floor will rot;
they erect logs, to which it will subsequently be attached topcoat floor, and lay the thermal insulation in even layers without gaps;
a layer of waterproofing, but it should no longer allow steam to pass through;
if the attic will serve as a living quarters in the future, the insulation is additionally covered with expanded clay, followed by its viscosity;
finishing.

How to properly insulate the pitched roof of a wooden house

first, the entire surface is covered with a waterproofing film. It is laid with an overlap so that no joints are formed with the help of construction tape;
then the insulation is laid. Mineral wool works well in its quality, but only in the form of mats. It keeps its shape perfectly and does not sag when in an upright position. Mineral wool is placed between the rafters and fixed by means of a lathing lathing or a nylon cord mesh;
the vapor barrier layer will not allow the steam in the air to penetrate into the thickness of the insulation, thereby reducing its technical characteristics, but at the same time will allow the thermal insulation to "breathe". The vapor barrier is attached to the rafters on top of the insulation and is fixed with construction tape;
finishing - fiberboard or chipboard plates, you can use drywall.

Over time, every owner of a private house thinks about insulating the attic. Indeed, every year the materials lose their original qualities, which leads to a loss of heat that goes through the attic.

Thermal insulation of a house is a priority that must be addressed before the onset of cold weather. So, as everyone knows that warm house - this is far from the one that is well heated, but the one that does not let all this heat through.

It should also be noted that the insulation of the attic of a private house with polystyrene foam or any other insulation will make it possible to significantly reduce heating costs.

That is why the question of how and how to insulate the attic becomes extremely relevant.

Typically, this kind of insulation is necessary in underutilized rooms. It is also important to note that they must necessarily be equipped with properly equipped roof ventilation.

The attic, together with its floors, performs a very important function, namely, it acts as a border between heat and cold. Here, a large amount of condensation accumulates and this happens as a result of intense exposure to moisture in the attic. And this must be taken into account when insulating your private house.

Many firms and companies offer such services, but very often it happens that the prices for their services are too high and many think about how to insulate the house on their own. You can insulate the house with your own hands. However, for this it is important to take into account all the features of the installation of one or another insulation.

All materials that can be used as insulation for the attic are described in more detail below. All the advantages, as well as their disadvantages, and everything so that at the end you can choose the most optimal option for yourself will be considered here.

But first, you need to determine the main types of insulation:

bulk;
slab;
roll;
sprayed.

It should be noted that each of the options has its own characteristics and can be used as insulation for the attic. It is important to understand that only the main materials that have received the most positive reviews are indicated here.

Thermal insulation with mineral wool, ecowool

Mineral wool is perhaps the most demanded material for warming a mountain today. This is a kind of classic in construction industry... After all, it is used by both professional teams and people who decided to deal with the issue of insulation on their own.

Such widespread popularity of mineral wool was achieved due to its excellent performance characteristics. Especially if you take into account the basalt mineral wool. It does not lend itself to combustion and just fits.

It is also worth considering some more of its benefits, which include:

Ease of use, while working with mineral wool there are absolutely no problems, even for those who insulate the attic on their own.
It has a "breathing effect" and it is due to this that a good microclimate is created.
Resistant to combustion.
Allows you to create good sound insulation.
Environmentally friendly material.
Many people note its property not to lose shape even over a long period of use.
It has a relatively low weight, which does not affect the main structure in any way.
Rodents and other pests cannot spoil it.
The minimum level of thermal conductivity.
One of the cheapest materials that is suitable for insulating the attic of a private house.

It must also be said that mineral wool is sold both in rolls and in slabs. And this makes it possible to choose the most suitable option, which will be easier for you to stack.

Important! If you decide to insulate the attic with mineral wool, then you should take care of both waterproofing and vapor barrier. This is due to the fact that this material is afraid of moisture. And if you ignore this moment, then after a while the mineral wool will lose its original appearance and its performance characteristics.

Insulation of the attic with polystyrene foam, polystyrene foam

Anyone who is wondering how to insulate an attic has an idea to use expanded polystyrene. And this is not at all coincidental, since this material is even more widespread than mineral wool. It is also used by professional builders in their work, and for independent work it fits perfectly.

The main feature that polystyrene possesses is an acceptable price. It is actually the cheapest building material that can be used as insulation for an attic.

It is also important to note that expanded polystyrene is much denser than cotton wool, and therefore it is a pleasure to lay it, since it is an "obedient" material. It can be easily processed and put in the right place.

In addition, a number of its advantages can be noted:

It keeps its original shape perfectly.
Resistant to moisture.
Low thermal conductivity, an order of magnitude lower than that of mineral wool.
The ability to create excellent sound insulation.

But along with a large number of advantages, this material also has significant disadvantages, which include the following indicators:

Highly flammable, just one spark is enough for the foam to smolder.
Does not allow steam to pass through, and therefore it is not possible to achieve the effect of "breathing walls" with this insulation.
If you do not additionally protect the expanded polystyrene, then the rodents will chew it with pleasure, and therefore you can end up without an attic insulation.

Despite all its shortcomings, polystyrene still remains one of the leaders in the field of attic insulation. After all, fires do not happen so often, you can use additional protection of the material against rodents, but the "breathing effect" is not so important on the hill.

Therefore, we can conclude that for such a low price, this is just a great option.

Blown insulation for the attic

This method of warming a hill in a private house is the most fashionable today. It is used by almost all companies that offer similar construction services.

The main advantage that this insulation for the attic has is that it independently fills all the space, voids and at the same time creates a uniform as well as continuous layer. You no longer need to cut blocks to fill all holes.

In Russia today, two blown heaters are used: blown wool and ecowool.

The latter consists of 80% cellulose fibers. They are also made from the most common waste paper, but the remaining 20% \u200b\u200bare a wide variety of additives, which can be boric acid, which acts as an antiseptic and blizzard as a fire retardant.

The blown wool is completely composed of standard minerals, which are intended for thermal insulation. It is important to note that it is highly crushed.

Thermal insulation with bulk materials: expanded clay

If you are still thinking about how to insulate an attic in a private house, then you should pay attention to expanded clay. This is one of the most simple ways insulate the attic and at the same time not contacting specialists.

Expanded clay is balls that are poured onto the floor, trying to distribute them as evenly as possible. As you already understood, they can only insulate the floor, the ceiling - it will not work, in any way.

The advantages of the material include the following:

Not flammable.
Resistant to low temperatures.
Possesses high strength.
Provides excellent sound insulation.
Environmentally friendly material that does not affect human health in any way.
It has a long service life.
Provides good thermal insulation.

The material is poured over the roofing material, the minimum layer should be at least 15 cm. In order to be able to walk in the attic, you will need to make a concrete screed.

Sawdust as insulation for the attic

The technical characteristics of this material are in no way inferior to modern synthetic insulation.

Important! Sawdust for insulation is used extremely rarely, since there is a large selection of other materials on the market that are much easier to work with.

Sawdust benefits:

Sawdust is an environmentally friendly material.
Low cost.
Long operational life.
Low thermal conductivity.
To create such a heater, you do not need any special equipment or special tools.

Polyurethane foam

This material occupies a leading position in the environmental safety table, and therefore you can safely buy it.

Important!This material shows excellent adhesion, and therefore can be used with absolutely any materials.

Characteristic properties of polyurethane foam:

does not lend itself to moisture;
high level of sound insulation;
practically does not give in to combustion.

Stages of attic insulation

In order for the insulation to serve for a long time and there are no problems with it, it is necessary to strictly observe the technology. This is the only way to be sure of the quality of insulation.

Preparing the attic

The first step is preparing the attic.

And first of all, it is necessary to put things in order in it, this means:

cleaning of all unnecessary items;
everything wooden parts should be pre-processed special compositionwhich protects the material from rotting, as well as from the formation of fungus;
if there are metal surfaces, then you should take care of them, or rather, treat them with a special primer or an anti-corrosion compound;
from all cracks, old insulation, rags, and sawdust should be removed.
if cracks are found in the attic, then they need to be repaired polyurethane foam.

The second stage is waterproofing

When insulating a mountain, this stage is one of the most important, since many materials do not tolerate moisture well and may even lose their original characteristics. That is why you need to take care of the good. Also, waterproofing prevents the appearance of corrosion on metal floors.

The third stage is laying the insulation

Depending on the chosen insulation, we begin to distribute it evenly over the floor, as well as walls and ceiling, if, of course, it is not expanded clay or sawdust.

It is important to ensure that all layers are the same, and there is no gap between the insulation. At this stage, you need to be as careful as possible.

The fourth stage is vapor barrier

The vapor barrier is a prerequisite, both for and for reinforced concrete. It must be laid directly on the ceiling, only in this way can it provide protection of the insulation from the generated vapors that can accumulate in the heat insulator passing through the ceiling.

Fifth stage - counter lattice

After the previous steps have been completed, you can proceed to the completion of the wall (roof) decoration. For this you can use various materials: lining, drywall or plywood.

Sixth stage - insulation of engineering communications

To do this, you can purchase mineral wool and wrap it around the pipes, and then wrap everything with roofing material and secure with wire. This is the easiest way to insulate communications.

As you can see, there are no special difficulties in insulating the attic. The main thing is to carefully follow the instructions and do everything consistently, and then you will be able to do this procedure no worse than professionals.

After all, now you yourself can choose the most suitable material as a heater.

From the author: hello dear reader. If you are reading this, I assume that you have a private house, and you decided to insulate the ceiling from the side of the cold attic with your own hands. If so, then further information is what you need to properly insulate the ceiling at home.

What you need to know before starting work

Where to start? .. The topic is quite extensive, and work related to insulation requires, if not professional, then at least basic knowledge about materials available on the market, their properties and methods of their application.

If you do a job without having this knowledge, you can, at best, spend time, effort and money, so to speak, on the wind, because of which, it is just cold, and at worst, provoke a fire due to neglect of fire safety rules and improper installation of insulation material. Yes, insulation is needed to keep warm, but a fire is already an overkill in every sense.

Now we will look at the most popular materials, and also find out with a cold attic using common types of insulation. We will find out what the advantages and, possibly, disadvantages of each of them are.

Insulation with foam

Polyfoam is one of the most popular materials for insulation. It is lightweight and easy to cut even with a conventional cardboard cutter. In short, working with foam is convenient, fast, pleasant and, in principle, not difficult. The main thing is to make the correct measurements and not cut off the excess from the whole sheet. But even if you overdid it, there is nothing fundamentally terrible in this: this place can be easily filled with polyurethane foam. Let's summarize the benefits of foam in a short list:

it is easy to cut;
easy to transport to the top;
it is not afraid of moisture and is not sensitive to temperature;
it is not suitable for consumption by insects and rodents;
if the foam is laid correctly - on a dry base treated with an antiseptic, the likelihood of the appearance of fungal formations (mold) is minimized;
the material has a relatively low cost.

The list goes on, but I think that's enough. We have listed the main positive aspects of the material.

But foam can also be different. Yes, there are different manufacturers, but that's not the point now. The fact is that sheets are produced in different parameters. In this case, we are interested in thickness.

For insulation of living quarters, sheets with a thickness of 5–7 cm are usually used, while their density, as a rule, is 15 kg / m³. of course, the higher the density index, the higher the material's ability to insulate. You can, of course, choose 25 kg / m³, you can lay the sheets in two layers - this is not forbidden.

But, nevertheless, there is a recommendation: if you are going to install an attic floor made of a hard material (for example, fiberboard / OSB-boards), then it is enough to choose foam with a density of 15 kg / m³. If the installation of a rigid surface is not planned, for better thermal insulation it is worth choosing sheets with a density of 25 kg / m³.

In general, if there is such an opportunity, then a hard floor should be installed in any case. This will allow you to store various things in the attic or even turn it into additional living space, if, of course, you equip it properly.

But if there is no hard surface above the sheets, then walking on them often, and even more so, moving objects is not desirable. Simply, they are not designed for this, regardless of what density index they will have.

Insulation from an attic in a wooden or brick one is fundamentally no different: both there and there the process consists in a simple laying of foam on the floor of the attic. More specifically, the following work has to be done:

check the entire wood structure for rot. If you find a rotten area, then it must be cut out and replaced with a new piece of wood, previously treated with an antiseptic. In general, it would be useful to treat all elements of the wooden structure with an antiseptic. Even if these measures were taken during the construction of the house, prevention will never be superfluous. Moreover, in matters related to construction;
clean the attic floor of debris (including small ones) - the base must be clean;
make the necessary measurements, make calculations;
cut the foam sheets according to the calculations;

lay polystyrene on the surface. Be prepared that this material will cost more than the foam itself, but this is fully justified. In fact, there are alternatives, and in some cases they can do without it at all;
lay cooked;
fill the gaps between the sheets with polyurethane foam. Distance between sheets and supporting structures also needs to be foamed.

Here is such a simple way to insulate a home from the attic with foam. Now let's move on to another, equally popular and effective insulation - mineral wool.

Thermal insulation with mineral wool

Mineral wool insulation is another equally popular method. Minvata is widely used for insulating apartments, houses, balconies, loggias. Moreover, both ceilings and facades. The range of its application is not less wide than that of foam.

Just like foam, mineral wool has its own advantages:

relatively low cost;
it is unsuitable for food for rodents and insects;
working with her is easy enough;
the material is considered to be hardly flammable.

But, among other things, mineral wool also has its own characteristic drawbacks, associated, for the most part, with its structure, with the nature of the material itself:

when wet, it loses its valuable qualities. of course, if a few drops of water get on it, nothing terrible will happen, but if your roof leaks with enviable regularity, dampness will accumulate in the cotton wool - then it will not only cease to perform its functions, the main of which is heat preservation, but also with time will become the residence of fungal formations. And the cultivation of such "mushrooms" in the attic is hardly part of your plans;
cotton wool cannot be pressed for the same reasons. No, this will not start mold in it, but its effectiveness will decrease by about 30-40%, depending on how you "try";
people with diseases of the respiratory system (for example, with asthma) should not look at mineral wool at all. But if you happen to work with her, then you need to use personal protective equipment - of course, not a gas mask, but at least a gauze bandage.

I would not say that the disadvantages of mineral wool are significant, so as not to consider it as possible option... Again, mineral wool is an affordable, reliable and widespread insulation. The main thing is to observe precautions and not violate the rules of operation.

As for the thickness, then, again, the thicker the layer, the warmer it will be in the room. Taking into account natural conditions, a layer of mineral wool from 15 cm to 30 cm or more is usually laid in attics.

Another important point: if you use several types of insulation (yes, this is also possible), then the bottom layer should be the least vapor-permeable. In other words, you can put mineral wool on foam plastic, but you cannot use foam on mineral wool. If there is a need for noise insulation, it is recommended to use a mineral wool with a density of 40 kg / m³.

So we come to the essence of this section. Getting started:

be sure (!) check the boards for rot. Outwardly, they may look intact, but if you hear a dull sound when hitting with a hammer - most likely, it is rotten inside. It should be replaced with a new antiseptic treated fragment. In general, the preparation is the same as when using Styrofoam;
checking the roof. If it leaks even a little, the mineral wool will not forgive you. Therefore, be sure to eliminate the leak;
checking communications. Although mineral wool is a hardly flammable material, it is still worth playing it safe;
we clean the surface of debris;
constructing wooden frame;
we lay the vapor barrier material. Just in case, I will say that the vapor barrier cannot be laid on both sides. If you suddenly want to spread it on top, resist this harmful desire. The condensate will have nowhere to evaporate, and then the mineral wool will start to slowly but surely sweat;

roll out the rolls between the beams (well, or lay the tiles);
we mount a wooden base;
enjoy the work done.

You can do without installing a hard floor. This is not necessary, but, again, it will not be possible to walk or put anything on the surface (remember that cotton wool cannot be pressed).

We have already reviewed two popular ways to insulate a house with a cold attic. Now let's look at other options. I must say right away that they are more labor-intensive, but, at the same time, more economical in terms of finance. One of these methods is the use of expanded clay.

Warming with expanded clay

Expanded clay is a material that is obtained through the firing of low-melting clay varieties. The resulting gravel is in the shape of oval pellets, and in color is something between brown and orange. The bulk density of expanded clay is also different - from 350 to 600 kg / m³ and more. Now it is not so important for us.

Consider the characteristic advantages and disadvantages of expanded clay. So, the advantages:

low price (as a rule, it costs several times cheaper than mineral wool or foam);
fire resistance - expanded clay does not burn at all;
high soundproofing ability - if this is, of course, relevant;
expanded clay is an environmentally friendly material: it does not emit any fumes into the air.

It would seem perfect. Yes, indeed, this is a great option for insulating a private house. There is only one specific detail: it is a porous material - and absorbing moisture, its weight increases, and its thermal insulation qualities decrease. If your house has a roof leaking (at least a little), the first thing to do before starting work is to repair the roof. Moisture is harmful, as we have already found out, not only for expanded clay, but also for mineral wool and for other alternative options.

Keep in mind that expanded clay is quite heavy - it is not foam or cotton wool. Therefore, before emptying it, make sure that the attic floor / ceiling of the room below is secure. If the boards are hemmed from below to the beams, there is a possibility that the first ones will not withstand the onslaught and will come off the beams. Then the expanded clay will be right in the room.

To make the under-roof space of a private house warm and even residential, it is necessary to insulate the attic from all sides - along the gables and roof slopes. This business is quite difficult and troublesome, given the slopes of the walls of the attic, to which the insulation will have to be attached. Here it is important to withstand the technology, so that the heat-insulating "cake" will serve for more than a dozen years and at the same time retain heat well. Therefore, the question is how to properly insulate with your own hands cold attic, it is worth considering in more detail.

Insulation options

Before considering the list of materials, it makes sense to clarify what the concept of "insulate the attic" means, since the choice of insulation depends on this. Some homeowners invest in this concept insulation of the ceiling and the hatch to the attic in order to reduce heat loss at home, and the under-roof space itself will remain cold. Others mean the thermal insulation of the roof slopes from the inside with an insufficiently insulated floor, as was done in old houses with clay.

Still others want to make the attic space exploitable and warm, for which, again, it is necessary to insulate the attic walls, which are roof slopes and side gables. It is about such thermal insulation that will be discussed in detail below. If we are talking about insulating the floor of a cold attic, then the choice of materials here is quite large:

expanded clay;
wood waste (sawdust);
glass wool in rolls (type ISOVER or URSA);
slab or rolled mineral wool (ROCKWOOL, KNAUF);
boards made of foamed polymers (polystyrene, extruded polystyrene foam).

Note. The list does not include options for insulation with polyurethane foam and ecowool due to their high cost, but we have given the most popular materials for the attic floor. In addition, it will not work to insulate the attic floor with sprayed polyurethane foam with your own hands without special equipment.

Now, from the list presented above, we will single out those heaters that are most often used to insulate the inclined walls of the attic. At cost, foam will be the cheapest, and its thermal resistance is high, as is the ability to repel moisture. One problem is that the material is flammable. Therefore, for those homeowners who are worried about fire safety your home, it is better to buy mineral wool based on basalt fiber. Only mineral wool absorbs moisture well, so it will be necessary to provide for its removal, which will be discussed later.

A few words about glass wool, which is also quite suitable for thermal insulation of the attic. It also does not burn, but high temperature will not be able to withstand, the material is charred at 200 ° C or more. If it is planned to make the attic space residential, then glass wool is not a place at all, it is harmful to human health.

Mineral wool insulation

As mentioned above, mineral wool is a porous material capable of absorbing moisture, as well as allowing vapors to pass through itself. Even if this insulation is protected on both sides with a vapor-tight film, then due to the temperature difference outside and inside the house, a dew point will appear in the thickness of the cotton wool. As a result, condensation will begin to form from the air that is already in the open pores of the material.

When insulating an attic with mineral wool with your own hands, you need to learn one rule: the insulation is insulated from moisture only on one side - the inside, and outside you need a ventilation gap (air). Thanks to him, moisture from the cotton wool will be removed, thereby preserving its thermal insulation properties.

Also, glass - and mineral wool is afraid of direct water ingress, which is why it instantly gets wet and ceases to be a heater. This means that from the side of the street it must be protected from wind and precipitation, while providing an outlet to the same side of water vapor. That is why it is more difficult to insulate an attic with mineral wool than with foam, which is vapor-tight. The diagram below shows the correct "pie" of thermal insulation of the inclined walls of the attic from the inside:

As you can see in the diagram, the insulation is laid in the openings between the rafters, but first a waterproofing film is laid between the rafter boards and the roof covering - a diffusion membrane. It is she who protects the mineral wool from direct moisture penetration, letting all the vapors out into the air, from where the ventilation air carries them away. The air must be arranged under the entire plane of the roof covering, as shown in the diagram:

Since the diffusion membrane is at the same time a protection against water that can get on its surface from the outside through the slots in the slate, the film sheets should be laid horizontally over the rafters, starting from the bottom. The canvases are laid with an overlap of 100 mm, and the joints are sealed with adhesive tape. When it comes to insulating an old house, where the slate is nailed to the sheathing boards without a membrane, you will have to mount it in strips vertically between the rafters.

Important. It is necessary to fasten the membrane strips to the side surface of the rafter board using a stapler and as often as possible, leaving a 5 cm wide airflow on top.

The next stage is to lay the insulation in the space between the rafters, for which it is cut into strips, whose width is a couple of centimeters wider than this gap. By the way, mineral wool manufacturers make slabs 600 mm wide, and rolls - 1200 mm, adapting to the standard pitch of rafter boards. In this case, additional fastening of the insulation is not required, then a vapor barrier film is laid and mounted interior decoration.

Like the sloping walls of the attic, the gables also need to be insulated. But here the composition of the "pie" depends on building material this roof element. If it is made of brick or timber, then it would be more correct to insulate the pediment of the attic from the outside, guided by the following scheme:

It is clear that such thermal insulation implies external insulation of the entire house, which is not always possible for various reasons. Then we continue to insulate the attic from the inside, vertically installing on brick wall wooden beams for further installation of insulation. Before that, do not forget to lay a diffusion membrane under the beams. The same is done if the pediment has an old structure - a wooden frame with an outer cladding of lining. The "cake" of insulation then looks like this:

Note. The same "pie" is used for internal insulation brick pediment of the attic. The masonry here plays the role of external cladding from the boards shown in the diagram.

Foam insulation

It should be noted that it is somewhat easier to insulate the attic with foam plastic than with mineral wool. First of all, because of the vapor tightness of this insulation, so it is not necessary to arrange an internal vapor barrier. But a diffusion membrane and air are needed in any case, because wood also participates in the "pie", which must also give off moisture somewhere. So the first stage of self-insulation of the attic is repeated as described in the previous section.

Styrofoam with a density of 25 kg / m3 is cut in such a way that it can be tightly inserted between the rafters. Then all joints should be blown out with polyurethane foam, due to which air circulation through the cracks is excluded and additional fastening of the insulation is provided. Then everything is simple: an interior finish made of plasterboard or other facing material is attached to the rafter boards.

Thermal insulation of the gables is done in the same way. It should be noted that this technology can also be used when insulating an attic with extruded polystyrene foam (penoplex). This modern insulation has higher performance than polystyrene, including in terms of strength. If it becomes necessary to lay the penoplex in 2 layers, the second can be attached to the first with ordinary self-tapping screws and glued with polyurethane glue.

Insulation of ventilation pipes in the attic

In modern private houses, the attic is often a technical floor where ventilation units and pipes for moving air are located - air ducts. If the temperature there is significantly lower than in the premises, then the air ducts must be insulated without fail and here's why:

the air passing through them is heated by energy sources paid for by the homeowner. It is unacceptable for the air to waste heat in a cold attic;
due to the temperature difference inside and outside the air ducts, condensation will constantly evolve.

The cheapest way to insulate ventilation pipes is to buy rolled mineral wool and wrap the air duct with it, fixing it with twine.

After that, a layer of mineral wool is covered with a special foil to prevent moisture from entering. But in a compressed form, the thermal resistance of the insulation roll is reduced, so it is better to use ready-made foam shells. They are put on the duct from both sides and are fixed with a knitting wire.

Ventilation pipes of rectangular cross-section are most conveniently insulated with a self-adhesive material made of polyethylene foam. This is an excellent vapor-tight insulation, in which one side is covered with a sticky layer that adheres well to a metal surface.

Conclusion

In fact, there are more materials and methods for insulating the attic, but we have brought the most affordable of them to do it yourself. For example, a layer of polyurethane foam does not require any "pie" at all, but it can be applied only if there are special units. So at the moment, foam plastic with mineral wool remains the most demanded heaters, as well as the technology for their use.