How to make a warm roof on the house. Complete instructions for installing a warm roof. Attic floor insulation

The role of the roof of the house in providing heat and a dry microclimate in the house is certainly great. However, it would be a mistake to assume that only by choosing the right material for the roof, quality can be ensured. In fact, they only cover a multi-layer system of various materials, and how to make a warm roof depends on the characteristics of each of them.

Roof types: cold or warm

Roofs can be classified as cold and insulated. The first ones are in houses that have a non-residential attic space, the thermal insulation of which is located on the attic floor. Therefore, the issue of insulation does not arise, since this is simply not necessary. On the contrary, the attic must be turned into a poorly ventilated area in order to allow vapors from the insulation to evaporate freely and to avoid condensation. quite simple: as a rule, these are rafters with a crate stuffed on them, on which they attach, and even then not always, waterproofing, and a roof.

But if there is a residential attic space right under the roof, it is necessary to insulate it. Moreover, it is necessary to perform insulation even in the case of a summer house. In summer, thermal insulation protects from the heat of the roof heated by the sun, and in winter, on the contrary, it does not allow the internal heat of the house to escape. Insulation also serves as sound insulation, especially if the roof is metal.

Before you make a warm roof, you need to clearly understand that it is a rather complex system of interconnected elements, in which each of them is important.

Insulated roof structure

The roof insulation device resembles the creation of a multilayer pie, only consisting of layers of hydro, steam and thermal insulation. The efficiency of the elements and their durability can be ensured subject to a certain sequence of arrangement of its layers.

thermal insulation

In a residential area, and the attic is just that, the temperature and humidity levels should be the same as in the entire building. This means that the thermal insulation of the walls and ceiling of the attic should not be inferior to the insulation of the main external walls of the building.

It is very important that the thermal insulation is done correctly, otherwise, damage to the supporting structure and loss of aesthetics of the interior finish can be expected.

Requirements for laying thermal insulation material

The insulation should not have cavities or cavities for the free passage of air.
It must completely fill the space provided for insulation.

Let's look at some typical insulation errors:

too small thickness of the insulating layer, the appearance of "cold bridges";
small insulation width, due to which the inter-rafter space is not filled;
a large thickness of insulation, due to which part of it overlaps the ventilation gap;
too large insulation width, as a result of which the insulation is squeezed out towards the ventilation gap.

Materials for thermal insulation

The heater is chosen, guided, in particular, by the following requirements:

good thermal conductivity,
environmental and fire safety,
soundproofing,
vapor permeability.

Styrofoam boards can be used for thermal insulation of both pitched and flat. When using this material, the vapor barrier can be omitted.

Glass wool has good sound, electrical and thermal insulation properties. However, it is hygroscopic and, due to the unstable mechanical structure on pitched structures, slides down over time. Fiberglass is therefore more often used in the thermal insulation of flat roofs.

vapor barrier

In order for the insulation to show its insulating qualities, it must be in a dry state. Any ingress of moisture into it can cause partial or complete loss of insulation properties and its decay in just one season. As a rule, it is humidified due to diffusion and further condensation of water vapor penetrating from the interior. Therefore, from the side of the room is necessary. For these purposes, a special metallized three-layer film is more often used. During installation, absolute tightness must be ensured. The joints of the canvases, the areas of interface with the walls are carefully glued using adhesive tape or sealing tape.

Hydro-windproofing

To protect the insulation from condensate, which is formed on the inner surface of the roofing, blowing, dirt, as well as the removal of vapors from the insulation, a layer of hydro-wind insulation is laid on top of it. These functions can perform

polypropylene films with microperforation;
films with anti-condensation coating;
diffusion vapor-permeable "breathing" membranes:

Reinforced films are distinguished by their high strength characteristics for tearing and puncture, however, the vapor permeability of the material is low. For this reason, with an excess of moisture, the perforation of the film is clogged, and it stops releasing water vapor from the roofing pie to the outside.

Next generation, films with anti-condensation coating are free from this shortcoming. Excess steam is absorbed into the pile and, without forming drops, is retained there until the effect of moisture stops. Then the anti-condensate layer dries in the air flow.

It should be noted that these materials cannot be laid in close proximity to thermal insulation. If during installation a ventilation gap is not provided for the passage of air, then the moisture accumulated in the insulation due to their insufficient vapor permeability will condense in it. And as a result - moistening of the rafters and battens, mold formation, etc.

breathable membrane- this is both a serious obstacle to external moisture and an almost transparent outlet for steam. The non-woven material underlying it has a high vapor permeability, therefore, unlike other similar materials, it can be laid directly on the insulation. Due to the absence of a ventilation gap, part of the under-roof space is freed up, and the space between the rafters can be used more rationally.

ventilation gap

The ventilation system is necessary to remove moisture from the under-roof space and the roof structure itself. The ventilation gap, which provides air circulation, forms a counter-lattice. If the roof is arranged correctly, then the air saturated with moisture from under it easily exits through the venkanals through the vents or aerators.

Roofing pie device

The first layer of waterproofing is laid. It is fixed over the crate and attached to the bars of the counter-crate with brackets. The material is laid with a slight sag, but not more than 10 cm.
Next, a heater is placed on top of the waterproofing. Installation of thermal insulation is carried out between the rafters, without gaps.
Depending on climatic conditions, you can lay another layer of thermal insulation. In this case, the seams of both layers should not coincide with each other.
The insulation is on top and fixed to the crate using a construction stapler. Sheets of film should be overlapped and glued with adhesive tape.
When laying layers between them, observe small distances.
From above, the roofing "pie" is closed, for example, with plywood sheets.

At present, a large number of Russians are tired of living in cities, building country houses and settling there. Many build these houses themselves, but not everyone knows how important a warm roof is in a house. It serves as the main part of the thermal insulation of the house and provides great energy savings.

Roof pie with insulation

The presence of a warm roof for the house is more important than the foundation. A house can stand on a poor and even bulk foundation, but you cannot live in a house without a roof.

Roofs are divided into two types. Cold and warm roofs. If the house has a non-residential attic, then it does not need to be insulated. If you are going to live in the attic or equip some kind of functional room, then you cannot escape the installation of a warm roof.

Warm roof waterproofing

A warm roof prolongs the life of the house, minimizes the occurrence of emergencies, and reduces the cost of maintaining the house.

Roof insulation

For the device of a warm roof, manufacturers produce various roofing insulation.

Most popular:

Roof insulation

Expanded polystyrene foam. Lightweight material belonging to the class of foams. Many experts consider it more effective than mineral wool. Operating time 50 years.
Polyurethane foam. It has a good indicator of thermal insulation and waterproofing, low vapor permeability. Service life is more than 50 years. It is applied to warming of a roof and a roof.
Stone wool. For the manufacture of plates using mineral wool. Apply to the device of a warm roof of roofs. The main advantages are: it does not burn, has a good level of thermal insulation, is little affected by rodents and microorganisms. The service life is more than 60 years.
Glass wool is one of the varieties of mineral wool. It serves as an excellent material for thermal insulation and arrangement of roof insulation. Has a long service life.

Consider several options for installing a warm roof:

insulation is located between the rafters;
insulation is located under the rafters;
the insulation is located above the rafters;
All these methods can be combined with each other.
Among the combined options for a warm roof device, the following are popular:
insulation is located above and between the rafters;
insulation is located under and between the rafters;
the insulation is located above and between, under the rafters.

To install a warm roof, we need various roofing and power tools:

Cutting tools - circular saw, electric jigsaw, hacksaw, roofing scissors.
Drill.
Screwdriver.
Hammer, rubber mallet.
Roulette.
Marker.
Sealant and polyurethane foam.
stapler.
Cord.

Individual features of each roof insulation option

Insulation is placed between the rafters.

roof insulation

The simplest and most popular option for a warm roof is the location of the insulation between the rafters. This method is used with complete thermal insulation of the rafters. From the beginning we produce waterproofing of the roof with a roofing film. It serves as protection against atmospheric moisture, for insulation and rafters. We fix it with a stapler. Staples choose a length of 10 mm. We mount the insulation along the entire height of the rafters. When installing thermal insulation, make sure that the insulation fits snugly against the rafters. Cut the roof insulation boards 15 mm more than the distance between the rafters. The insulation plate has good elasticity and fits snugly between the rafters.

This device of a warm roof is attractive for its simplicity and low cost. Roof insulation work can be carried out in any weather after you have installed the roofing film.

A significant drawback of this option for roof thermal insulation is the possibility of forming cold bridges.

Insulation is placed on top of the rafters

When using this option of roof insulation, the interior trim is mounted. A vapor barrier is laid on it, all its joints are glued. The insulation laid on top forms a thermal circuit. A waterproofing film with high vapor permeability is laid on top of the thermal insulation.

Roof with heater

This option of roof insulation reduces the formation of cold bridges to a minimum.

disadvantage This option of roof insulation is the difficulty of providing work with roofs of non-standard configuration.

The heater is located under the rafters. This option of insulation is almost never used in suburban construction.

Combined roof insulation

The device of an insulated roof using a combined method, when the insulation is located under and between the rafters, is the most popular and is often used in practice. This looks like an option when the insulation is mounted between the rafters with their full insulation, with an additional inner layer of insulation that is mounted between the transverse bars. The rafters completely overlap. The transverse beam has dimensions equal to the dimensions of the insulation.

Lay a vapor barrier film between the layers of insulation. One nuance should be taken into account here - the thermal resistance of the roof insulation from the inside should not exceed 20% of the thermal resistance of the insulation laid between the rafters. If this balance is disturbed, then condensation will be deposited on the vapor barrier film.

Alternatively, the vapor barrier film can be mounted from the inside of the roof, but then there is the option of damaging it during other work.

Simple flat roof insulation

The device of a warm roof according to this scheme is optimal if you do not have great financial resources. Such a warm roof device is characterized by ease and accessibility of installation and allows you to achieve effective thermal insulation of the roof due to inexpensive materials.

The option of installing insulation above and between the rafters is the most expensive and time-consuming. It is possible that you cannot do without assistants and professionals. Most often it is used when building a new roof and replacing the old roofing.

A successful installation of a warm roof requires a special understanding of the purpose and properties of all materials used. A constructive approach to their choice, special knowledge and skills are important. If the homeowner has a clear idea of how to arrange a “roofing cake” on the roof of a country house, then he will not only be able to build a quality roof, but also create comfortable conditions for living in the house for a long period of time.

Image 1. The device of a warm roof.

When creating a warm roof, it is necessary to take into account not only the climate of the region, but also the shape of the roof, the angle of inclination of the structure, the strength of the floors, etc. Creating a “roofing cake”, that is, a warm roof, requires a number of layers, as shown in the figure (PICTURE one). The design should include vapor barrier and waterproofing, ventilation gap, lathing, rafters, as well as roofing.

When choosing a heater, you can opt for mineral wool, expanded clay, basalt slabs, glass wool, polystyrene foam, polyurethane foam. To facilitate the installation of the structure, you can choose the width of the slab, which corresponds to the gap between the two rafters. For residential attic spaces, the roof is insulated not only from the outside, but also from the inside. Otherwise, it is not necessary to do so.

Ways to insulate roofs of various shapes

Shed roofs are supported by two parallel walls of the building, supporting an inclined surface. Gable roofs can have the shape of a regular rectangle. If the roof is hipped, its slope has the shape of an isosceles triangle. This requirement assumes that in most cases the roofing elements are rectangular in shape. This facilitates the installation of thermal insulation, eliminating the possible appearance of an unclosed wedge, to close which will require cutting and fitting the roofing material. This method is incorrect, since the installation of a warm roof requires sufficient material and time resources. As a result, the appearance of the building will be spoiled.

For isosceles slopes of the hip roof, the use of cutting material for the roof in one or two templates is required. For a good economy of materials, you can use their halves, laying these elements on opposite sides of the slopes. Individual cutting of roofing materials for two slopes will be needed when, by mistake or due to negligence, the roof slopes will be at different angles of inclination. This will entail an increase in the time to complete the work twice, but not saving materials.

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Warm roofing technology

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Required materials and tools and the procedure for performing work

In the process of installing the roof of a wooden house, you will need:

axe;
level;
plumb;
roulette;
a hammer;
plywood;
film;
construction stapler.

The work is carried out in the following order:

The waterproofing layer is attached to the bars of the counter-lattice with the help of brackets, taking into account its sagging.
The insulation is laid in such a way that there are no gaps between the rafters.
If necessary, a second layer of insulation is laid in such a way that the seams of the two layers cannot coincide.
The vapor barrier film is fixed with a stapler to the crate.
The film is overlapped, which is fixed with adhesive tape.

It should be remembered that a warm roof is mounted by hand so that there is little space between the three layers so that condensation does not occur.

The resulting "pie" is closed with plywood.

For a long time in Russia, there were no problems with roof insulation at all: straw was knitted or reed was dried, and that’s it - the roof of the house was reliably protected from both rain and cold. But modern coatings do not have heat-insulating properties at all, and with all the development of progress, up to 30% of all heat flows through such a roof.

Therefore, if you do not want to warm the atmosphere, study the roof insulation from the inside in detail - in this article we will reveal all the points!

Conventionally, roof insulation in the construction world is divided into attic, when the roof slopes are insulated, and attic, when the ceiling is thermally insulated.

Like this? We can say that attics also have their own attic - this is a ventilation gap between the internal insulation and the laid roofing. The fact is that according to all the laws of physics, heat always rises and looks for its way out into the atmosphere. It passes both through the insulation and through the vapor barrier, and together with water vapor. And then, in the eaves plumb line, outside air is drawn in, which passes to the ridge and along the way picks up with it both vapors and excess heat. Through aerators or the same skate, all this is safely removed and does not cause any problems.

Those. in an ordinary, unused roof, the attic occupies the entire space from the ridge to the attic floor, and in the attic, the attic is just a small space under the slopes between the insulation and the roofing. And in the insulation of both, the type of roof is its own approach, which we will now study.

Cold roof insulation technology

If your roof is cold, then the heat-insulating layer should not be on the slopes, but on the floor of the attic. It is here that it stops the heat flow coming from below and prevents the cold from the roof from descending into the lower living space. As a result, the temperature in the attic is kept within + 1-2 degrees, the roofing material is not heated. In fact, such an attic serves as a necessary air gap between the living rooms of the house and the thin roof slab.

All rolled, slab and loose heaters are suitable for attic flooring. Because the overlap of the slope does not have, it does not have any special requirements for the heat-insulating material used: nothing will crumble and will not be exposed.

Pay attention to the fact that after the insulation of the roof, properly organized ventilation remains in it: there must be dormer windows opposite each other, ventilation ridges and aerators, and in the cornices - round-the-clock access for outside air suction. As a result, the temperature in a non-residential attic space should be as close as possible to the street temperature, and the living space is already separated from it below - competent thermal insulation of the floor.

Now let's take a closer look at the insulation of a cold roof.

Warming with mineral wool

When insulating the attic floor with mineral wool, first of all pay attention to the distance between the slats or logs - it should be slightly less than a roll or mat of insulation.

Usually, the thermal insulation of the internal space of the roof is complicated by the uneven surface of the attic floor, its height differences, a large number of rails and bars, not to mention ventilation pipes and electrical wiring:

Ecowool insulation

If you want the house to breathe and the steam to easily go up, then insulate the attic floor with modern ecowool:

Insulation with blown wool

Recently, blowing - roof insulation with blown wool has become increasingly popular. The Japanese "insulation" Esbro-Vul II is used here, which does not emit dust, and therefore does not create problems. And the blowing method itself is actually quite simple:

Step 1. We put a vertical ruler on the floor and mark the required height for spraying mineral wool.
Step 2. Apply insulation in an even layer to the desired level.
Step 3. We lay the insulation so tightly that it has 25 kg of weight per cubic meter.

Note that this type of insulation in Japan is the most popular, and has already found many supporters in Russia.

Glass wool insulation

And finally, glass wool - if you do not use the attic at all. The fact is that even glass wool closed under the crate sometimes causes irritation of the ENT organs. Why do you have to wear a respirator and goggles when working with it:

Insulation with sawdust

When insulating the roof with sawdust, follow these instructions:

Step 1. First of all, you need to protect the wooden structure. To do this, we first apply an antiseptic composition, then fire-bioprotective mixtures, and on top - water repellents.
Step 2. The next step is to put a substrate (you can use cardboard) and close the seams and cracks, if any, with foam (large) or sealant (small). At the end, we cut the foam that has come out and equalize it with the beams.
Step 3. Now we fill up the sawdust, in two layers: first a larger fraction, as well as chips, and then a fine one, so that dust does not form in the room.
Step 4. But so that rodents do not start on the attic floor, in addition to sawdust, mix dry lime and small broken glass.

Warm roof technology

The mansard roof is a special design. Here, too, there is a cold attic, only it is very small, because. the insulated attic ceiling is almost closely drawn to it with the help of an additional crate. In fact, there is only space for ventilation, and no more. And ventilation serves to ensure that the heat from the attic does not touch the roofing, on which the snow in winter should remain as a heat insulator, and not melt.

Here is a vivid example of the most standard situation of improper insulation of the attic: they install the cheapest 15 cm rafters, put fluffy mineral wool in two layers of 5 cm each and cover it all with roofing. Ventilation - only 5 cm, without inflow and exit, because There was no expert around to advise. As a result, in summer - unbearable heat, from which even air conditioners do not save, and in winter - generous frost on the roof. And all because street air is heated most of all in this scheme. In other words, the very small attic that we talked about must be, and far from 5 cm.

And especially carefully in such a roof you need to think over the vapor barrier:

And further. The material for the manufacture of rafters is always designed for a certain weight. So, a roof under soft tiles can also be built from drywall profiles, only it cannot be insulated with heavy basalt wool. Also, the mansard roof needs good forced ventilation so that the insulation does not rot and deteriorate. Therefore, carefully read all the points of the master classes prepared by us:

Warming with mineral wool

Follow this simple guide:

Step 1. We install hydro and wind protection. If possible, use modern membranes - they are stronger and more durable. In any case, fasten the material with an overlap, and glue all the joints with construction tape.
Step 2. Now we measure the distance between adjacent rafters.
Step 3. Using a regular or clerical knife, we easily cut the insulation into the desired pieces and insert it between the rafters.
Step 4. We install an additional crate between the membrane and the inner lining.

Please note that you need to fasten the vapor barrier membrane with the smooth side to the insulation, and the fleecy side already inside the room.

If the distance between the beams is not more than 60 centimeters, it will be more convenient for you to use square insulation mats:

Step 1 Inside, under the rafters, it is desirable to finish off the rough crate - so that the insulation has something to rest on. Make the distance between the bars about 20-30 cm. Ordinary uncut wood with medium-sized nails is quite suitable for this purpose, it is only important that the bars are of the same thickness.
Step 2. After installing the rough crate inside the structure, remove all dust and dirt with a construction vacuum cleaner.
Step 3. Next, we process everything wooden with a special remedy for fungus, rot and mold. Just use for this purpose not a spray gun, which is less effective, but an ordinary paint brush. With its help, you can achieve deep penetration of the product into the wood, and this is important.
Step 4. Let the product fully absorb and dry for two to three days.

As a result, all your sheets should lie tightly - a little denser than you need at first glance. This is the only way to avoid the presence of cracks and subsequent freezing of the roof.

And one more thing: ordinary mineral wool boards are not very suitable for insulating roof slopes, because. they do not hold well between the rafters, but the pediments can be insulated with them.

Glass wool insulation

To insulate the roof slopes, get the best glass wool from well-known manufacturers. Such glass wool practically does not contain dangerous glass dust, which most of all annoys workers. Also, even after laying, it does not emit harmful substances, which is even confirmed by the Finnish Institute of Health. After all, it is one thing to throw this “thorn” on the floor of an unused attic, and another thing to cover it with clapboard in a billiard room or private office on the attic floor.

Combined insulation

If desired and expedient, it is possible to insulate the roof from the inside with two different types of heaters at the same time. But one important point must be taken into account - vapor permeability. The fact is that when choosing different heaters for an effective combination, we usually only summarize their heat-insulating properties. But their steam capacity is completely different!

And, if, for example, you put mineral wool down during insulation, and then foam plastic on top, then the water vapor that got into the cotton wool will begin to tend to the colder part of the roof and bury itself in an absolutely non-breathable foam plastic. As a result, all the insulation will simply suffocate and “please” with mold. But on the contrary, it is possible: first we put polystyrene on the bottom of the rafters, and on it already - mineral wool. If some steam passes through the vapor barrier and the gaps between the foam plates, it will easily overcome the mineral wool and enter the ventilation duct. Therefore, there is such a rule: the top layer of insulation should always have high vapor permeability and thermal conductivity.

And, finally, if a warm roof is to be used as a sauna or an additional bathroom, the insulation and roofing cake in it must be thought out especially carefully.

When building a house, it is important to create warmth and comfort, which helps a lot with a warm roof.

The creation of a heat-insulating layer is a very important stage, which, in addition to the main function, also performs soundproofing.

How to choose a heater

The technology itself, according to which the roof insulation will be carried out, depends on various climatic factors of a particular region.

So, the thickness of the material for insulation is calculated based on the lowest temperatures in this area. To get the maximum effect, during the roof insulation with your own hands, it is recommended to combine materials.

When making a choice of those, it is necessary to take into account such nuances as:

the climate of the region;
the thickness of the walls of the structure;
the level of strength of the roof, as well as its shape and angle of inclination.

To insulate a mansard roof, it should be covered with good thermal insulation materials. But in order to create thermal protection for the attic floor, it is already possible to use cheaper bulk options in the form of sawdust or expanded clay. At the same time, it is important to remember that proper thermal insulation of the roof will help to maintain a reliable state of the structure of the entire building for a longer time.

Roofing cake features

The most popular option for roof insulation, and at the same time very easy for self-construction, is considered the “Canadian sandwich”.

This technology involves the creation of a multilayer coating. The arrangement of such a roof does not require the involvement of specialists, the main thing is to follow the correct sequence of laying all layers.

It is important to prevent moisture from entering the insulation. To do this, it is necessary to create conditions under which condensate will not appear. To accomplish this, just such elements as wind and moisture protection, vapor barrier, hydrobarrier, as well as the creation of small gaps between these layers for ventilation are needed.

You also need to create air circulation in the gaps from the bottom to the top. Due to this, all the resulting moisture will not fall on the heat-insulating layer, as it will evaporate and be removed due to ventilation in the gaps.

This is important to do, since mineral wool or any other similar insulation must always be kept dry so as not to lose its properties.

Roof preparation

First of all, for the work it is necessary to draw up a clear work plan, as well as select the materials that will be used.

Any roof, regardless of its type, has several parts, external and internal. So, its outer part is directly the roof, and the inner part consists of floor slabs, as well as a frame of rafters.

In order for the roof to serve for a long time and provide high-quality insulation, it is necessary to first carry out certain preparatory work.

First of all, you need to get rid of moisture, as well as any other negative elements on its design, such as rust, mold and even fungus. To do this, the surfaces are cleaned with a metal brush, after which it must be coated with anti-corrosion agents.

Note: those sections of the roof and walls that were affected by mold or fungus must also be treated with antiseptics.

Overview of heaters

Regardless of the type of roof in the house, if it has not been insulated, the house will lose on average up to a quarter of the heat generated. Therefore, you need to wisely approach the choice of thermal insulation material.

To simplify installation, it is better to choose plates that correspond to the existing distance between the rafters. Otherwise, areas will be formed through which cold will pass, which will significantly reduce the quality of insulation.

In the case of using rolled heaters, their width must also be selected based on the distance between the rafters.

In total, the insulation can be chosen from a large number of options, each of which has its positive and negative sides:

. This material is relatively cheap and very easy to install. It has excellent thermal insulation properties. However, glass wool should only be used together with some kind of waterproofing, since if moisture gets on it, it loses most of its insulating properties.
. It has almost identical properties as glass wool, but its service life is much longer and is almost 50 years.
. This material is highly resistant to fire. However, similarly with glass wool, it loses its properties if it gets wet.
. It is one of the most affordable heaters, but it is very effective. It is produced in the form of plates of different sizes, which makes it possible to use it for arranging almost any type of roof. The main disadvantages of this material are its fragility, as well as susceptibility to rodent habitation.
. Its main advantages are environmental friendliness, as well as fire resistance. In addition, this material is resistant to various biological influences. However, its use is possible only on horizontal surfaces, due to its shape. At the same time, expanded clay has a greater weight than mineral wool.
Polyurethane foam. It is a liquid insulation with very low thermal conductivity. It is applied by spraying on pre-prepared waterproofing. Indispensable for quick and easy thermal insulation. (Read about roof insulation with polyurethane foam).

Operating procedure

The insulation technology of the “Pie” type will be the same regardless of the type of building. In this case, all work should be done after the roof has been made and roofing materials have been laid on it.

All work is carried out from within:

First, waterproofing is laid in one layer. It must be fixed to the crate to the bars, using brackets for this. The material may sag a little, but not more than 10 cm.
Next, the heater is installed. In this case, there should be no gaps between it and the rafters.
If necessary (if the weather in the region is very severe), you can lay another layer of insulation. At the same time, its seams should not be next to the seams of the first.
Now the insulation needs to be covered with a vapor barrier film, for this it can be fixed to the crate using a stapler. In this case, the sheets must be overlapped and connected with construction tape.
There should be a certain distance between each layer of such a cake so that moisture does not linger in the roof.
From the inside, such insulation must be covered with plywood sheets, and if it is used as a living space, it can be upholstered with a decorative coating.

How to avoid mistakes

Any well-insulated roof should also have the right appearance. To achieve this, you need to accurately measure in advance all the indicators of the structure from the width and length to its height, as well as the diagonal.

Usually, in this case, unpleasant moments are revealed that prevent the creation of the correct roof. This may be a big difference between the sides of the house or in the distance between the lags, due to which the building has received an irregular shape.

Therefore, to ensure proper thermal insulation of the roof, it is necessary to eliminate various structural defects in time. It is necessary to carry out the installation of the rafter system only after the evenness of the slope, as well as the roof ridge, has been achieved.

If this is not done, then in the future, so-called cold bridges will appear in the “roofing cake”, through which heat will leave the house. They are areas where the integrity of the insulation is broken.

It's important to know: when a lot of icicles begin to form on the roof in winter, this will mean that there are gaps in the insulation of the building, due to which the roof is heated by warm air and the snow melts on it. To eliminate this, you need to additionally insulate the roof with felt.

Dry, and most importantly, a warm roof is the key to a comfortable and cozy atmosphere in the house. At the same time, the insulation does not only keep the house warm in winter, but also allows you to keep cool inside it in the heat.

Watch the video in which the specialist explains in detail the nuances of warming the roof of the house: