Do-it-yourself roof insulation from the inside. Proper insulation of the roof of a house: technology and video How best to insulate the roof in a private house

A well-calculated and high-quality installed rafter system, a durable, reliable, non-leaking roofing covering – all this is wonderful. But we must not forget about one more thing - about effective thermal insulation of your home from the upper direction, that is, from the side of the roof and attic floor. Insufficient or improperly performed insulation of these building elements not only causes less comfortable living conditions in the house, but also, most importantly, sharply reduces the normal service life of many building materials and structures constructed from them.

Typically, issues of roof thermal insulation are thought through at the design stages of the rafter system or attic floors, and the insulation system itself is installed in parallel with construction. But if suddenly, due to certain circumstances, it turns out that the roof in a house purchased, for example, is not insulated at all, or the effectiveness of thermal insulation is clearly insufficient, the owners will have to seriously address this issue on their own. That’s when the information on how to insulate the roof of a house with your own hands, given in this publication, will come in handy.

Why is it necessary to insulate the roof?

First of all, you need to have a very precise idea of how important it is to insulate the roof outside or inside.

The climatic conditions in most regions of Russia cannot be called “mild” - even in the southern regions there are often very harsh winters. Heating costs during the cold season usually become prevalent and “eat up” a considerable part of the family budget. But with poor-quality insulation, spending on energy literally turns into “money for air.”

Look at an approximate diagram of heat losses of an uninsulated or insufficiently insulated private house:

A roof with a roof that does not have effective thermal insulation simply “steals” almost a third of the energy costs spent on heating a home. Of course, we can’t even talk about any kind of efficiency. But even with such a completely unjustified expenditure of funds, it will be almost impossible to create a truly comfortable microclimate in the house.

With the arrival of the summer heat, the lack of thermal insulation also becomes a serious problem. A large roof area acts as a kind of “solar collector”, heating up in the sun and then transferring this flow of thermal energy down to the premises of the house. As a result, there is nothing to breathe in the rooms, or climate control equipment works with increased intensity, which, again, leads to completely unjustified costs.
The lack of thermal insulation has a very negative impact on the condition of building structures. Normal human activity is always accompanied by the release of large volumes of water vapor, which condenses at the boundary of heat and cold, at the so-called “dew point,” turning into water. Oversaturation of wooden parts of the roof structure with moisture leads to the activation of rotting processes, to the destructuring of wood due to freezing and thawing cycles with the appearance of deep cracks, to the appearance and development of colonies of pathogenic microflora - mold and mildew, and to the appearance of insect nests.

Many home owners are wondering whether to insulate the roof of their house from the inside with their own hands. An insulated roof has several advantages over a cold one. In this article we will talk about how and with what to sheathe the inside of the roof, and what is required for this.

Advantages of an insulated roof:

Thanks to insulation, heat loss can be significantly reduced, up to 15% of the total losses. In view of the periodic increase in the cost of electricity and the constant desire to reduce the volume of its use, this solution will come in handy.
After insulation, the house will have additional living space located under the roof, which can be used for your own needs.

Insulation of the roof from the inside can be carried out when, for some reason, the owners made such a decision during its operation.

It is worth noting that it is possible to achieve high-quality insulation, maintain warmth and comfort in the house, and also extend the service life of the roof if you use only high-quality materials.

If, according to the project, insulation is provided initially, then it is best to do it from the outside, even before the roofing material is laid. As a rule, you cannot do without this if you decide to build a house in an area with unfavorable weather conditions.

What is a house roof pie?

A roofing pie is a layered structure that includes roof insulation elements. At the heart of this design is a rafter system that holds the remaining elements. In cross-section, such a pie has a clear sequence of elements, the first of which is the roofing material.

The roofing pie consists of the following layers:

roofing;
lathing or continuous covering;
counter-lattice to form a ventilation gap;
waterproofing;
thermal insulation;
vapor barrier;
lathing for internal cladding;
internal lining.

The finished structure will reduce heat loss in winter, and in summer it will eliminate overheating of the space under the roof. It will also prevent precipitation from reaching the thermal insulation from the outside, and water vapor from penetrating from the inside of the room.

What materials are needed for the roofing pie?

How effective the insulation of the roof from the inside will be depends not only on the thermal insulation material, but also on the hydro- and vapor barrier. All other components of the roofing pie do not have a significant effect.

It is worth noting that the roof structure is constantly exposed to the following types of loads:

the mass of the entire roof is a constant factor;
precipitation and method of roof operation;
temperature changes;
ultraviolet radiation;
chemical reagents dissolved in the air;
windage of the roof and resistance to air flows passing through the attic;
moisture and condensation accumulating inside the attic.

Functions of waterproofing and vapor barrier materials

The purpose of waterproofing is as follows:

Prevent moisture from penetrating the insulation from the outside.
Help remove excess moisture from the insulation that has penetrated from the room.

For waterproofing, special film and membrane materials are used. If we are talking about waterproofing film, then it is a three-layer material with micro-perforation, the central layer of which is a polypropylene mesh, laminated on both sides with polyethylene.

Membranes are non-woven materials in which hydro- and vapor barrier is provided by the central layer, and the outer ones are designed to impart strength. Such materials are usually called superdiffusive. The advantages of membranes over films are that they are better permeable to vapor, therefore, there is no need to create an air gap before installation.

If, before insulating the roof, a waterproofing film is installed inside, it should be laid with some clearance so that excess steam can be freely discharged. Without such an indentation, the insulating material will quickly begin to get wet and cease to perform its direct functions. The durability of membranes is significantly greater than that of films.

As for vapor barrier materials, their main function is to create a barrier for moist air from inside the room so that it does not enter the insulation. As a rule, a vapor-proof film is used for this.

Types and characteristics of materials for do-it-yourself insulation

Before insulating a finished roof, you should decide on the material for interior work.

The choice should be made taking into account the following characteristics:

Density. This indicator directly affects the quality of heat transfer of the material. The lower the density, the higher the porosity. As porosity increases, the thermal conductivity of the material decreases, which means its thermal insulation properties increase.
Heat transfer. This indicator affects not only the degree of porosity, but also the temperature and humidity level of the material. As these indicators increase, heat transfer also increases.
Ability to absorb moisture. To prevent the insulation from absorbing and retaining moisture between the fibers, it is treated with special hydrophobic substances. In particular, the presence of such treatment should be clarified when purchasing mineral and glass wool.
Flammability.
Ability to withstand low temperatures.
Chemical resistance.
Environmentally friendly.

Based on the indicated characteristics, the optimal materials for insulating a metal roof from the inside are the following varieties:

Mineral and glass wool. You can purchase such materials both in the form of individual slabs and in rolls. In terms of fire resistance, mineral wool is slightly superior to glass wool.
Polystyrene foam or polystyrene foam. Available in slabs or extruded products. This material is quite flammable and releases toxic substances when burned. Therefore, it requires additional fire protection.
Polyurethane foam. This material can be presented in the form of panels or liquid compositions. The latter are applied to the roof surface using special equipment, so specialized teams of builders are engaged in such work.

Method of insulating a roof from the inside - how to insulate it correctly

There simply cannot be a single approach to the process of roof insulation, since each case will have its own subtleties. It all depends not only on the roof configuration, but also on the roofing used. In particular, if a soft roof is used for the roof, the roof should be insulated from the outside, even before laying the material. In addition, the technology for fixing the insulation in the case of flat and folding roofs will also vary. That is why it is very important to know how to properly insulate a roof from the inside in one case or another.

If the waterproofing film has not been laid beforehand, insulation must begin with its fastening. Please note that the ventilation gap must be at least 2 cm. Alternatively, additional slats can be nailed to the rafters or sheathing.

A superdiffusion membrane will be the best choice, since there will be no need to create an additional gap between it and the insulation.

To ensure reliable insulation, the material is fixed in several layers - at least two. In this case, you can avoid through seams between pieces of material. The thickness of the insulating layer will be about 15-20 cm. If the thickness of the rafter legs is less than this value, then the insulation is also mounted on top of the rafters. In this case, the lathing for interior decoration will press both the insulating material and the vapor barrier.

It will be more difficult to attach insulation to a flat roof. Since there is no additional support for the insulation, several bars need to be nailed to the ceiling so that the distance between them is less than the width of the insulation material, and the height is equal to its thickness.

Next, rolled material or special plates are tightly inserted between these bars. In addition, they can be attached with mastics or special glue. At the next stage, the insulating layer and vapor barrier film are fixed with lathing for internal finishing material.

Of course, a high-quality insulated roof will not only save money on heating and retain as much heat as possible, but also make your stay in the house cozy and comfortable. True, thermal insulation materials must be of high quality, so that you do not have to replace them soon and spend additional money.

It is necessary to insulate the roof of a house only when it is planned to make the attic spaces residential. If an attic is not provided, then it is not the roof that needs to be insulated, but the ceiling. The quality of roof insulation has almost no effect on the microclimate in the rooms; this is an unnecessary waste of time and large financial resources.

Currently, the construction industry has mastered the production of a wide range of products with excellent performance indicators. Such a wide choice often puts inexperienced developers in a difficult position. They only read manufacturers' advertising brochures, and based on this information it is difficult to make a specific choice. All companies describe only the positive aspects of their products and do not talk about the negative ones. The article will provide objective comparative characteristics of various materials used for roof insulation. This information will allow you to make an informed decision in each specific case.

By what physical parameters are insulation materials classified?

Insulation property	Short description
	You should first pay attention to this indicator. Heat loss occurs in two ways: infrared rays and convection. The lower the body temperature, the less rays it emits. Significant energy losses by infrared radiation occur at high heating temperatures of solids. For a roof, such losses can be ignored due to the low temperature. But the thermal conductivity coefficient is crucial. The parameter is determined in W/m×K. The thermal conductivity values of different bodies differ by several orders of magnitude. For example, the thermal conductivity of wood is approximately 0.15 W/m×K, and that of foam plastic is 0.015 W/m×K. This means that it retains thermal energy ten times better than wood.
	A very important indicator for all buildings, fire safety regulations have strict requirements for the safe operation of buildings. All materials are divided into several groups, from non-flammable (NG) to highly flammable (G4). The classification is carried out according to SNiP 21-01-97 standards and depends on several parameters: gas temperature, degree of damage along the length and weight and duration of spontaneous combustion. The non-flammable category includes mineral wool and expanded clay, and low-quality foam plastic belongs to the highly flammable category. The resistance class must be indicated on the packaging. It should be noted that the most modern polystyrene foam insulation, due to various additives, has a reduced flammability class (G2 and G3) and is allowed for limited use in residential construction.
	A conventional value used to classify potentially hazardous materials. It is established on the basis of changes in the amount of harmful fumes, assigned taking into account the concentrations dangerous to the human body. The classification is made taking into account the provisions of GOST 12. 1. 007-76 and SanPiN 2. 1. 4. 1074-01. Construction materials are subject to strict regulatory control; substances of class III (moderately hazardous) and class IV (low-hazardous) are allowed for limited use. Mineral wool, expanded clay, and glass wool are completely safe. The fourth class includes only some types of foam plastic and liquid insulation; it is recommended to use them carefully.
	The thermal conductivity of water is much higher than that of insulating materials. Accordingly, the more water they can absorb, the lower the final heat saving indicators. Another disadvantage of high water absorption is that wet materials in prolonged contact with wooden structures cause the appearance of rot and fungi. As a result, the wood loses its original properties, and the rafter system and cladding have to be repaired prematurely. The situation with the rafter system is especially unpleasant; its restoration not only requires a lot of time and money, but can also be done in warm and dry weather. And this greatly complicates repair work. Unfortunately, mineral wool has high water absorption; in order to prevent it from getting wet, it is necessary to carry out a complex of complex and expensive special construction measures. This is its significant drawback. Foam-based insulation materials absorb moisture the least.
	The higher this indicator, the more heat is removed from the insulation, the lower the heat saving values. And in this indicator, mineral wool is significantly inferior to foam plastic; it is freely blown by the wind. Even pressed mineral wool has this drawback, although to a slightly lesser extent than rolled mineral wool. To reduce energy losses, mineral wool insulation must be protected from the wind, and the shelter must allow steam to pass through. If the steam cannot escape, condensation processes will begin and the cotton wool will get wet with all the negative consequences. Modern diffusion membranes are used for shelter; they are quite expensive.
	The parameter characterizes the resistance of insulation to the effects of various active chemical compounds. There is always smog in city air, and it contains various chemical compounds. More stable than all mineral wool insulation materials, polystyrene foam at certain concentrations can react negatively to certain compounds. But this is only possible in cases of a critical increase in concentration; in practice, these situations happen very rarely.
	The rafter system of a house constantly changes its linear dimensions. The reasons may be violations of construction technology and calculations, excessive snow and wind loads, changes in the relative humidity of wooden elements. Insulation materials must constantly compensate for their dimensions without losing their strength. Mineral wool works best in such conditions. Foam materials can compensate for vibrations up to certain limits; if they are exceeded, the sheets are destroyed.
	For roof insulation, this parameter is not of great importance. But there is one caveat. Mineral wool ranks last among the insulation materials used in terms of strength. If the angle of inclination of the slopes is large, then over time it can shrink or sag under its own weight, cracks form, the effectiveness of thermal insulation decreases, and very unpleasant cold bridges appear. If the angle of inclination of the slopes exceeds 20°, then it is recommended to take measures to fix the mineral wool.

As can be seen from the table, there is no ideal roof insulation for all cases; each has its own strengths and weaknesses. They must be taken into account before making a final decision.

Performance characteristics of roof insulation

Let's consider the most used modern materials; there is no point in talking about the currently rather exotic bulk insulation materials. Not only are they almost never used, but they are also far inferior to modern technologies in all respects. What is the most common way to insulate a roof today?

Prices for mineral wool

Mineral wool has now almost completely replaced glass wool.

What are its advantages over traditional insulation?

Lower thermal conductivity values. Mineral wool has a thermal conductivity of 0.03-0.05 W/m×K, glass wool has a thermal conductivity of 0.41 W/m×K. The higher the density of mineral wool mats, the higher the thermal conductivity. In practice, the difference in thermal conductivity can be neglected; it is leveled out due to the gaps in the places adjacent to the rafter system.
Elasticity and manufacturability. These indicators are interconnected, so it makes sense to consider them simultaneously. Glass wool manufacturing technology assumes that the diameter of the fibers will be approximately 15 microns, the diameter of mineral wool fibers is much smaller and does not exceed 2–8 microns. This explains the difference in terms of manufacturability and elasticity. It is difficult to work with glass wool; thick glass fibers damage and irritate the skin; you need to use gloves and a respirator. Mineral wool is much softer and does not have such disadvantages. In addition, it is more elastic; after removing static loads, it completely restores its original thickness. Glass wool cannot be completely restored; thick glass fibers break.
Weight. It has a significant effect in the case of a large slope of the pitched roof. If the slope is large, the material may deform under its own weight. According to this performance indicator, mineral wool is ahead of glass wool.

With regard to environmental friendliness, fire resistance, hygroscopicity and chemical resistance, the materials are almost no different from each other. But there is one note - the cost of mineral wool is much higher than glass wool.

The service life of mineral wool is practically unlimited, but provided that the material is not damaged by rodents.

Mineral wool can be rolled or pressed. How do their performance characteristics differ?

It has a thickness from 5 cm to 15 cm. The width of the sheets is standard 60 cm, the length may vary for each manufacturer. The advantages of such cotton wool are the speed of installation. The sheets are tightly inserted between the rafters and are kept from falling out by taut ropes; no additional fixation is required. Cotton wool can be easily cut with an ordinary mounting knife.

The material is tightly rolled into rolls, and after removing the packaging, the factory thickness is restored. It has two advantages: low price and the ability to insulate rafter systems with complex geometries.

Prices for expanded polystyrene

Widely used modern insulation material. The density, depending on the specifics of the manufacturing technology, ranges from 16–30 kg/m3; the higher the density, the greater the load the insulation can withstand.

There are brands of polystyrene foam that do not support open combustion; they melt, and fire occurs after a strong increase in temperature. Such expanded polystyrene can be used for insulating flat roofs of multi-story buildings; there are no restrictions for private houses. For example, paper ignites when heated to +2300°C, wood at +2600°C, and modified polystyrene foam spontaneously ignites at a temperature of +4900°C.

Expanded polystyrene is very afraid of hard ultraviolet radiation, but for roof insulation this does not matter, the material is located under the roof covering. Service life is approximately thirty years. The slabs are easy to cut; all roof insulation work can be performed without special expensive tools and devices.

To reduce the number of cracks, they need to be foamed with construction foam.

Practical advice. Professional builders strongly recommend using high-quality imported foam; it has high elasticity. Domestic materials crack when compressed - the fixation strength of the plates decreases, and thermal conductivity increases.

Expanded polystyrene is almost non-hygroscopic; in two days of direct contact with water, it absorbs no more than 2% of the volume of moisture. Such low values have no observable negative impact on performance.

Thermal conductivity depending on density 0.028–0.034 W/m×K.

Polyurethane foam

One of the least flammable plastic insulation materials, it can be used in liquid form. But such insulation of the roof of a private house has more disadvantages than advantages and is not recommended by professional builders. It is much more profitable to do insulation with ready-made slabs. Up to 99% of the pores are closed, which almost completely eliminates moisture absorption, thermal conductivity, depending on the type of polyurethane foam, is 0.019–0.028 W/m×K. Service life of at least 20 years if manufacturers' recommendations are followed, withstands frosts down to -160°C.

The material is technologically advanced; the release of harmful chemical compounds into the air does not exceed the norms controlled by state standards. Weight no more than 60 kg/m3, has excellent adhesion to all building materials, which simplifies the process of finishing the internal surfaces of attic spaces. One of the important advantages is that it is little damaged by rodents. For example, slabs of foam plastic can be completely turned into dust by a mouse within one year.

Penoizol

It is characterized by very low weight (from 10 kg/m3), thermal conductivity in the range of 0.036–0.038 W/m×K. The difference between the material and other types of polymers is a large number of open pores, which increases vapor permeability to 0.21. Vapor permeability is a positive parameter for roof insulation - excess moisture is removed without problems, and the risks of condensation are minimized. But there are also problems. Condensation not only increases thermal conductivity, but also destroys the insulation when it freezes.

It does not support an open fire on its own; the service life is at least 50 years, but subject to several conditions:

penoizol must be reliably protected from UV rays;
relative humidity should not exceed the current tolerance ranges.

Penoizol insulation with a thickness of only 5 cm provides the same thermal protection of structures as 7.5 cm thick foam plastic, 12.5 cm thick mineral wool or 34 cm thick wood.

The material is easily cut with an ordinary hacksaw, but in the process a lot of small crumbs are formed. It is necessary to take measures to prevent it from getting into all areas of the house.

Liquid insulation

Some polymer materials can be sprayed onto the roof in a liquid state. This method has no advantages, but only some disadvantages. Let's list just a few of them.

These are not all problems, you can add to them an increase in time and cost, a large influence of the human factor, etc.

Modern and fashionable insulation, manufactured from recycled materials. More than 80% of the composition is recycled cellulose, the rest is fillers and binders. To insulate the roof, it is recommended to use pressed ecowool; it is easier to work with, and its performance indicators are much superior to powder wool. Thermal conductivity is in the range of 0.032–0.040 W/m×K, density up to 75 kg/m3, vapor permeability 0.3 mg/m×h×Pa.

Relatively large weight can create difficulties when insulating the roof; additional loads must be taken into account at the design stage of the rafter system. To increase fire resistance, a fire retardant is added to the material; inhibition of the development of microorganisms is achieved by adding boric acid. As can be seen from the composition, there is no reason to call such a material absolutely environmentally friendly.

A wide selection of insulation materials by name, unfortunately, does not mean an equally wide selection of performance properties. Minor differences in thermal conductivity do not play a noticeable role. They are nullified during certain deviations from the recommended insulation technology, and such deviations will always exist.

Practical advice on choosing insulation for the roof of a private house

Prices for windproof membranes

Windproof membrane

There are several practical tips that will provide real assistance when planning work on insulating the roof of a private house.

Correctly calculate the estimated cost of work. The costs must include not only the price of the insulation, but also the cost of its delivery. If the work is carried out independently, then it can be ignored. But if construction companies are involved, the estimated cost of insulation increases significantly. Most of them simply price their services - they are equal to at least half the cost of all materials. But these are minimum values; there are companies whose cost of services exceeds the cost of purchasing insulation materials.

Wind protection for roofing

These are synthetic modern membranes with a fairly high cost. In addition to the membranes, you need to make a counter-lattice for natural ventilation - add the cost of lumber and hardware.

Compare the technical characteristics of various insulation materials. At the same time, you should not pay much attention to thermal conductivity indicators; it differs only slightly. The weight and elasticity of the material are important for longevity. Information should be taken not only from manufacturers’ websites about the benefits; look for practical user reviews. Especially those who, for one reason or another, had to deal with roof repair work after it was insulated.

Soberly assess the complexity of the recommended technologies with your capabilities. The roof is not a building element with which you can experiment. Even seemingly insignificant violations of technology can cause very big problems for the structure as a whole.

Before starting work, you need to prepare materials and tools in advance. Do not allow interruptions in insulation due to a shortage of insulation or other materials. After work resumes, some previously installed structures will have to be dismantled, and this costs money.

Always try to buy insulation of the required thickness. If, taking into account the climatic zone of residence, the thickness of the insulation should be 15 cm, then it is much more profitable to buy sheets of the same thickness, rather than making three layers 5 cm thick. You can come across assurances that if three layers are laid with offset joints, cold bridges will be eliminated. This is not true, there are no cold bridges where there are completely no joints, that is, in the entire slab. In addition, one slab of polystyrene foam or mineral wool 15 cm thick costs less than three 5 cm each. And lastly. It is much faster to install one layer of insulation than three.

It is not recommended to begin insulation immediately after the construction of the roof is completed. We need to wait for the first rain and make sure there are no leaks. Noticing and eliminating problems that have arisen due to a violation of the roof’s tightness after insulation is much more difficult and will always cost several times more.

Video - Insulation for the roof of a private house

A house built and furnished with one’s own hands is the real pride of any owner. An integral stage in the arrangement of any residential building is the internal insulation of the roof. And if in most cases no problems arise with the thermal insulation of walls, then the insulation of the roof structure can confuse an untrained craftsman. Therefore, before starting the practical part, study all the theoretical recommendations proposed below.

After installing the insulation and all related elements, the roofing system will look like a layer cake. The design is based on a rafter system. All other elements are laid and secured onto it.

Modern roofing “pie”

In the classic version, the layers of the pie, starting from the finishing roofing, are placed as follows:

roofing;
lathing for installation of finishing material. Can be solid or sparse;
counter-lattice bars. Needed to create a ventilation gap under the roofing material;
waterproofing film;
thermal insulation material;
vapor barrier material;
lathing for installation of insulating materials and internal cladding;
inner lining material.

A properly installed roofing pie will significantly reduce heat loss in cold weather and prevent overheating of the space under the roof in hot weather. Waterproofing will protect the insulation from atmospheric moisture, and the vapor barrier material will prevent the formation of condensation and the occurrence of all related problems.

How to insulate?

The modern market offers a huge range of materials that can be successfully used for internal roof insulation. Try to avoid excessive savings - materials must be of high quality.

Insulation parameters

When choosing a suitable insulation, you need to pay attention to a number of basic characteristics of the material, namely:

weight. The heavier the insulation, the more significant load it will place on the roof. This imposes a number of additional requirements on the rafters and sheathing - their configuration and strength must correspond to the characteristics of thermal insulation;
thermal conductivity. It is better for this parameter to be as low as possible, if possible no more than 0.04 W/m*C;
resistance to adverse external influences.

Preferred insulation materials

Not many materials meet the above requirements. Among all the existing insulation options, professionals recommend giving preference to mineral wool insulators and foam panels. All other things being equal, mineral wool is more preferable.

Additional insulation materials

In combination with insulation, the roof will need to be additionally insulated using vapor and moisture insulation materials. For roof waterproofing, polyethylene and roofing felt are usually used. These materials are highly resistant to moisture.

The vapor barrier layer is best equipped using special membranes, glassine or modern foil materials.

Regardless of the chosen insulation (installation is still carried out in the same sequence), during the work process you must adhere to a number of basic recommendations, without which you cannot count on high-quality internal insulation of the roof.

All the rules can be combined into one brief summary of tips, namely:

Thus, even before starting thermal insulation work, the master needs to study a fairly large amount of information and remember a number of important requirements. The work must be done to the highest possible quality. Properly equipped insulation will make living in the house as comfortable as possible and will significantly reduce the cost of heating the premises.

Use the recommendations received and remember: insulation must be done with the obligatory installation of vapor barrier and moisture barrier layers. Only such a complex will make it possible to obtain a reliable, durable roofing system that is resistant to any adverse external influences. It’s better to immediately do everything according to the rules and live peacefully in a safe home than to patch holes in the roofing pie after every heavy rain.

Preparing for roof insulation

The insulation procedure remains almost the same regardless of the type of roof, materials used and other points. Having understood the main points of thermal insulation work, you will be able to successfully apply them in practice.

First of all, carefully prepare the roof for the upcoming internal insulation.

First step. Inspect the rafter system. If you find rotted or damaged elements, replace them with new parts.

Second step. Treat all wooden elements with an antiseptic.

Third step. Check the condition of pipelines and electrical wiring if these communications are laid under the roof.

Guide to internal roof insulation

Start working on the internal insulation of the roof. The event is held in several stages. Go through each of them sequentially, not forgetting the recommendations received earlier.

It is assumed that the rafters, sheathing and other necessary elements have already been installed and all you have to do is install the insulating materials and then lay the final roofing covering.

The first step is vapor barrier

Lay the film with a 10-centimeter overlap. To attach the vapor barrier to the bars, it is convenient to use a construction stapler with staples. Double-seal all joints with duct tape. Be especially careful and thorough when sealing various difficult areas, such as the junction of the film with pipes, walls and other structural elements.

The second step is insulation

EKOTEPLIN - roof insulation

Place the selected insulation into the cells of the sheathing. Usually the sheathing is assembled so that the step between its bars is a couple of centimeters less than the width of the insulation, so you can place the insulating boards as tightly as possible. The sheathing bars themselves must be nailed to the rafters perpendicular to them.

If you really want, you can do without lathing - you hammer nails along the edges of the rafter legs and stretch the wire between them. It will hold the insulation boards. However, it is better not to give up the sheathing - it is safer with it.

The insulation itself is usually laid in 2 layers. In this case, the top layer must be laid with a certain offset in relation to the bottom one - it is impossible for the joints of the insulation boards of both layers to coincide.

Third step - waterproofing

Place the waterproofing film so that it completely covers the insulation, sheathing and rafters. To fix the film, it is most convenient to use a construction stapler with staples.

Place waterproofing under the roof overhang - this will create the conditions necessary for effective water drainage in the future.

At the end, all you have to do is lay the selected roofing material on the roof.

Thus, although independent internal insulation of the roof is a very important and responsible undertaking, there is nothing overly complicated in its implementation. Do everything in accordance with the instructions, and very soon your home will become truly cozy and warm, and heating costs during the cold season will significantly decrease.

Happy work!

Video - Do-it-yourself roof insulation from the inside

Experienced builders know that it is better to think through all technological issues related to roof construction at the stage of creating a private wooden house project. An accurate plan of construction work allows for high-quality and quick insulation of the external insulation of the slope, if required. In real conditions, you often have to insulate the roof from the inside with your own hands after completing the roof installation. In this article we will talk about the internal thermal insulation of slopes, how much it costs, and how it is done.

Internal thermal insulation is the process of home insulation from the attic side using materials that have low thermal conductivity. This measure to optimize the temperature regime of a wooden private house is used only if the roofing work has already been completed, since it is impossible to cover the slopes with insulation without dismantling the roof covering. The internal method of installing heat-insulating materials has the following features:

The minimum thickness of the insulation layer to stop heat loss through the slope is 150 mm. Therefore, insulating the roof from the inside reduces the usable area of the roof space, which is considered a disadvantage when equipping residential attics of a private wooden house.
The insulation during internal thermal insulation of the roof is located directly under the wall lining material, so more vapors saturated with moisture penetrate into it, despite the vapor barrier layer. For this reason, the material gets wet, losing its thermal insulation properties, and then wrinkles and settles.
Insulating the roof from the inside is considered a less convenient method, since when installing the slab of thermal insulation material, you have to hold it above your head. The difficulty of the work significantly increases the cost of internal insulation of the roof of a private wooden house.
The internal thermal insulation of the slopes allows the use of only the safest materials that do not harm human health during installation and operation. Considering how much environmentally friendly and hypoallergenic insulation costs, external thermal insulation would cost 1.5-2 times less.

Note! Thermal insulation materials for insulating the roof of a private wooden house are used in combination with waterproofing and vapor barrier membranes or films. Since without protection from the penetration of moisture or steam, they quickly become damp, which increases thermal conductivity and sharply reduces the effectiveness of insulation. For heated mansard roofs, in which these processes occur more intensely, professional builders recommend using forced ventilation.

Materials

The modern construction market has hundreds of different types of insulation, the cost and performance characteristics differ significantly. Vapor-permeable, moisture-resistant and non-flammable materials with low thermal conductivity are suitable for thermal insulation of the roof of a private house made of wood. The most commonly used types of insulation are:

Mineral wool. A fibrous material produced in the form of rolls, mats or slabs, the composition of which is based on threads of glass, gabbro-basalt or slag. Low cost, fire resistance, efficiency and ease of installation make these insulation materials the most convenient for doing the work yourself. The only drawback is that small particles that get on the skin, respiratory tract, or mucous membranes cause severe irritation. Therefore, installation is carried out in full equipment - with safety glasses, gloves, a respirator and a robe.
Expanded polystyrene. Insulation based on polystyrene foam is known to most people as polystyrene foam. It is often used for internal insulation of slopes, due to its light weight, high degree of protection against vag and low thermal conductivity. Foamed polystyrene foam is called polystyrene foam, in which air occupies more than 95%. Thermal insulation materials based on polystyrene foam are easy to install, they are easy to cut and fasten, however, they almost do not allow steam to pass through, which during internal insulation causes dampness in the room. This negative effect of using polystyrene foam can be reduced by using forced ventilation system equipment.
Polyurethane foam. Polyurethane foam is produced in the form of panels or a liquid mixture, which is foamed using a special installation that supplies carbon dioxide, and in this form is applied to the inner surface of the slope. This type of insulation is often used for roof thermal insulation, however, it has a significant drawback - complete vapor permeability. This property excludes the possibility of using this material for insulating wooden houses. In addition, due to the use of expensive installation, polyurethane foam installation is rarely done with one’s own hands.

Important! Use inside a residential building tightens the safety requirements for insulation for the health of home occupants. Ecowool is one of the tested safe materials. It consists of cellulose or flax fiber with the addition of antiseptic substances and fire retardants. Ecowool has thermal insulation and noise-reducing characteristics similar to mineral wool.

Installation methods

Installing thermal insulation material from the inside is more difficult and takes longer than from the outside when laying the roofing. However, if the roof is already ready, then homeowners have no other choice. To insulate the slope you will need insulation, a vapor barrier membrane, a construction stapler, a sharp knife, a marker, wooden slats, a screwdriver and self-tapping screws. There are two methods of internal thermal insulation:

Important! If the angle of the roof slopes is 25 degrees or less, problems may arise with laying insulation between the rafters, since the slabs will simply fall out of the opening under their own weight. To hold the material on the slope, it is secured with slats or fishing line stretched perpendicular to the rafters in several rows.