To understand how to insulate the roof of a house, you need to know how it is structured, the features of its design and operation. For flat roofs alone, the domestic company TechnoNikol offers almost forty schemes of technical solutions. For pitched roof There are fewer such solutions, but there are different options here too. And if you consider that this company is not the only one that produces roofing materials, and each other has its own established schemes, then a non-professional may get confused. But regardless of the technical nuances and characteristics of the materials, the principles of roof insulation are general.
Principles of insulation
There are two broad classes of roof construction: flat and pitched (or attic). And if we talk about functions, then there are also two of them: protection from atmospheric phenomena and thermal insulation.
In a flat roof, both functions are combined in one “pie”, which has the following arrangement of layers: ceiling, thermal insulation, roofing.
Insulation of a pitched roof can have three fundamentally different options:
cold attic with insulated ceiling;
exploited or a residential attic with an insulated roof:
combined roof with a warm contour of a dedicated attic.
But regardless of the design and location of the thermal insulation, all schemes have a common fundamental rule on how to properly insulate the roof of a house - on the side of the warm room, the insulation must be covered with a continuous and unbroken layer of vapor barrier materials. And the design itself must ensure the weathering of moisture from the insulation.
There are two main reasons for protecting insulation from getting wet - loss thermal insulation properties and an increase in the weight of the roofing pie. And if the loss of thermal insulation properties, apart from discomfort, does not threaten anything serious, then an excessive increase in the load on the supporting structure of the roof can lead to its collapse. In addition, vapor barrier in a pitched roof protects wooden structural elements from rotting and loss of load-bearing properties.
Insulation of a flat roof
Insulation technology flat roof depends on the floor materials and operating conditions.
Insulation of a flat wooden roof
Usually flat wooden roofs considered as a "sign" frame house. This is precisely the scope of application that is indicated even in the “proprietary” description of roofing systems of companies producing thermal and waterproofing materials TechnoNikol. But also in brick houses a wooden flat roof is not uncommon, since with a relatively light weight of the structure it is possible to ensure sufficient rigidity and strength of the roof of a low-rise building.
The insulation scheme looks like this:
Base. Moisture-resistant OSB board (class 3 or 4).
Vapor barrier film. Spread the strips overlapping by 15-20 cm on the long side and on the short side (when increasing in length). Along the perimeter, the vapor barrier should rise to the parapet and adjacent surfaces by the same 15-20 cm. Polymer-bitumen vapor barrier films are attached to the base using glue or telescopic fasteners (together with thermal insulation). Polypropylene or polyethylene film can be spread without attaching to the base, fixing it around the perimeter to the walls of adjacent surfaces using self-adhesive vapor-tight tape.
Insulation for the roof of a house. Three types of materials can be used for thermal insulation of a flat roof: stone wool mats, extruded polystyrene foam, and rigid polyisocyanurate foam boards.
Roof covering.
Perhaps the most common example of a flat insulated roof over a wooden floor is a terrace with access from the second floor. But in this case, the design of the roofing pie is closer in structure to the insulated ceiling of a cold attic.
On our website you can find contacts construction companies who offer roof repair services. You can communicate directly with representatives by visiting the “Low-Rise Country” exhibition of houses.
As roofing flat roofs use roll roofs waterproofing materials, which allow you to perform continuous and continuous upper layer. But, as with the insulation of a pitched roof, the waterproofing layer must be “breathable”. There are two main options for installing a breathable flat roof:
application polymer membranes with high mechanical strength and resistance to direct exposure to ultraviolet radiation;
two-layer bitumen coating– fused rolled insulation on top, a substrate with ventilated channels on the bottom (for example, Uniflex Vent).
The advantage of a wooden flat roof is that a slight slope is created due to the position of the floor beams. And it is needed even on a flat roof to drain precipitation into the drain.
Insulation of a flat roof over a concrete floor
This type of insulated flat roof accounts for the most options for constructing a roofing pie.
To begin with, there are unused and used flat roofs. Moreover, “exploitation” can be completely different character– from the terrace as a recreation area to the arrangement of the so-called “green roof”.
If we do not take into account the different options for roofing, then on a concrete floor the same sequence of layers is used as on a wooden one, except for one nuance - organizing a slope to drain precipitation into an external or internal drainage system. And here several solutions can be used:
device for covering screeds with a slope;
installation of a bulk slope-forming layer of expanded clay on the concrete base, separated from the insulated roofing pie reinforced screed;
installation of a bulk slope-forming layer of expanded clay over a layer of extruded polystyrene foam or mineral wool, followed by laying screed and roofing;
installation of a slope-forming layer from special slabs or thermal insulation mats, in which one surface is located in relation to the other with a slope.
Insulation of a pitched roof with a cold attic
Insulation of a pitched roof with a cold attic occurs along the ceiling. And depending on the flooring material, the patterns differ slightly.
Insulation of concrete attic floors
The layout of the layers is partially reminiscent of the insulation of the floor of the first floor:
A layer of vapor barrier is spread over the ceiling (overlapping strips, with gluing of joints and abutments to the enclosing surfaces).
Install logs (lathing) for laying the heat-insulating layer.
Lay thermal insulation. Typically, non-combustible materials are used as thermal insulation for the roof of a house - stone wool mats or loose expanded clay.
Lay a layer of waterproofing with high vapor permeability. According to the standard, laying a strip 1 m wide from the line of intersection of the ceiling with the external walls is required. When insulating the attic floor of a private house, the procedure is simpler - lay a waterproofing membrane over the entire area.
A spacer strip is attached along the joists (needed for a ventilated gap).
Installing the attic floor.
Insulation of the wooden floor of a cold attic
The insulation scheme for a wooden floor differs fundamentally in the location of the vapor barrier. The vapor-proof film is not attached to the floor beams from above, but is hemmed from below.
Video description
How to properly make hydro- and vapor barrier insulation of a cold attic floor, see the following video:
If you do the opposite, then water vapor from warm air will penetrate into the pores of the wood, but will not be able to erode - there is a vapor-proof barrier on top. This will cause you to get wet. wooden elements load-bearing structure and no treatment with antiseptics will save the wood from waterlogging and rotting.
The scheme for insulating the wooden floor of a cold attic looks like this:
On the side of the room there is a vapor barrier, on top of which there is lathing for decorative finishing of the ceiling. Vapor barrier can be of several types: simple film, with an anti-condensation surface, with a reflective (reflective) surface. In addition to protecting the thermal insulation from getting wet, it protects the room from insulation particles getting inside.
Thermal insulation between beams is stone wool mats or expanded clay.
A layer of waterproofing superdiffusion membrane.
Distance bar.
Attic flooring.
Insulation of pitched roofs
This type of insulation of the roof of a house is used for arranging attics or if it is installed in the attic engineering equipment(for example, a hydraulic accumulator, expansion tank, fan coil or ventilation system recuperator).
The standard roof insulation technology has the following scheme:
On the rafter legs, a waterproofing superdiffusion membrane is stuffed from bottom to top in overlapping strips. Vertical joints when extending the membrane in length must overlap and be on the rafters. Subsequently, the lower edge of the waterproofing is glued to the drip line (to drain condensate into the gutter).
On top of the waterproofing, a counter batten is nailed to the rafters, which provides a ventilation gap between the membrane and the roofing. To seal the fastening line, an elastic tape can be laid between the lath and the waterproofing.
Mineral wool mats are laid between the rafters.
WITH inside rafter legs are attached with a continuous layer of vapor barrier. If it has an anti-condensation or reflective surface, then it is turned towards the attic.
Place a spacer strip on top of the vapor barrier. It is necessary for the “correct” functioning of the anti-condensation or reflective layer. The second purpose of the slats is the sheathing for internal lining attic space.
A combined insulation scheme is used when highlighting “ warm circuit» attics. The principle of this scheme is to insulate the vertical fences inside the attic and only that part of the roof that is adjacent to the attic.
Video description
The following video is a demonstration of insulating an attic roof with two layers of stone wool:
Conclusion
Roof insulation is perhaps the most complex look among all thermal insulation works on enclosing surfaces. Only a professional can understand the variety of schemes for different types of structures and materials. And the choice of insulation and the calculation of the thickness of the thermal insulation layer depend on the design. In addition, it is necessary to provide and arrange your own roof and attic ventilation system, without which the insulation will get wet and lose its properties, and the wooden structural elements will begin to rot.
The most important condition for comfortable living in your own home at any time of the year and with the lowest possible costs for energy resources used for heating and air conditioning is a reliable Moreover Almost all areas of the building must be insulated. Roofing is no exception, which, by the way, is not always remembered by inexperienced novice developers.
If you look at the percentage of heat losses of any building that does not have proper thermal insulation, you will see that the “lion’s share” of them falls on the attic floor and roof. The specificity of this section of the overall structure of the house also imposes special requirements on the materials used for its insulation. Let's try to understand this issue to help the reader eliminate possible mistakes and make right choice. So, what is the best roof insulation?
The need for roof insulation
First of all, it is necessary to dispel doubts about the need for roof insulation. Let's start with this.
The limited area of land for building a house, and simply considerations of the most efficient construction with the lowest possible costs, often encourage owners to make useful use of the attic space. Attic “floors” are very popular these days, when the attic turns into a full-fledged living space, no different from other rooms in terms of convenience and comfort. You can also place a utility room in the attic, for example, a warm pantry, office or workshop.
It is clear that with this approach to beneficial use in the attic, there is no doubt about the insulation of the roof. Whatever type of roofing is chosen, none of them will provide the required protection from winter cold. And in the hot summer, the roof slopes heat up to such an extent in the sun that staying in an uninsulated attic becomes not only uncomfortable, but even completely intolerable from the heat. This, by the way, should never be discounted - insulation, or more correctly, thermal insulation of the roof helps to ensure an optimal microclimate in the attic at any time of the year.
But what about those whose immediate construction plans do not include converting the attic into a useful space? Maybe limit yourself to only high-quality thermal insulation attic floor?
How is the attic floor insulated?
The ceiling of a room bordering on top of an unheated and uninsulated attic becomes not a “bridge”, but an entire “highway” for heat losses. This can be eliminated by performing a whole range of thermal insulation works. – read in a special publication on our portal.
Of course, we can limit ourselves to this. But it would be better to listen to the arguments in favor of insulating the roof slopes, even if this is associated, of course, with additional costs:
- All details of the rafter system and the internal arrangement of the attic will be protected from the destructive effects of temperature and humidity changes. Therefore, the durability of the entire roof structure as a whole will increase.
- Energy efficiency increases sharply when considered on a building-wide scale. That is, the insulation of the roof, even with high-quality thermal insulation of the attic floor, will still make its “mite” in achieving the most comfortable conditions during minimum costs from an external energy source.
- Most modern insulation materials have the ability to effectively absorb sound vibrations. Insulated roof slopes will not become “resonators” during heavy rain or hail. This is especially true for roofing materials traditionally considered “noisy” - metal or slate.
- Finally, what seems unnecessary or temporarily unfulfillable today may turn into a pressing need in the future. This means that current circumstances may lead the owners of the house to think about the need to expand usable area due to the attic space. It’s better to have a warm attic right away than to do it from scratch later, which can often involve remodeling or replacing individual elements rafter system that has already experienced long-term negative influence of external factors. Sometimes such work cannot be carried out without temporarily removing the roof covering. In short, it will be much more expensive. So it makes sense to think ahead in advance.
Criteria that roof insulation must meet
To make the right choice, you need to know the criteria by which this material should be evaluated. There are many of these criteria, and it should immediately be noted that not a single insulation material fully meets all of them. So you often have to choose which advantage to give preference to.
So, the “ideal” material for thermal insulation of a roof seems to be one that meets all the following requirements:
- Of course, thermal insulation qualities should be placed in the first position. The material must have low thermal conductivity, that is, create the maximum possible resistance to heat transfer under specific application conditions. This indicator can be assessed by looking at the thermal conductivity coefficient, which must be indicated in the list of thermal insulation characteristics. To insulate the roof, where you can’t really “scatter” with the thickness of the insulation and the weight of the thermal insulation structure, they try to use materials with a thermal conductivity coefficient of no more than 0.05 W/m×C°. And the lower this figure, the better.
- The second most important thing is the density of the material. Nobody needs unnecessary overloads on the rafter system. So the less the insulation layer that is sufficient to create comfortable conditions weighs, the better.
- The problem with many insulating materials is their excessive hygroscopicity, that is, the ability to absorb moisture literally from the air. And overmoistening always leads to at least a loss of thermal insulation qualities. This means that ideally the insulation should have a minimum moisture absorption, and even better – pronounced hydrophobicity. This is especially important in roof conditions, where exposure to moisture cannot be avoided.
- The insulation material must maintain its qualities over a wide temperature range. That is, thermal insulation should “work” equally well both in extreme frosts and in the peak of summer heat.
- The most important qualities of a material, especially used for roof insulation, are indicators fire safety. This concerns fire resistance, the ability to become a flame spreader, smoke generation, toxicity of combustion products. Ideal material it seems completely non-flammable, but, alas, in this matter many insulation systems are far from doing well.
- The stability of the material, that is, its durability under real operating conditions. An ideal insulation should not change shape or volume, be resistant to chemical or biological decay, spontaneous or due to external negative influence of one type or another.
- The insulation should not serve as a breeding ground for microorganisms, nor should it be an attractive place for nests of insects, birds, and mice. And this, by the way, is also a very difficult problem to solve.
- Thermal insulating material during operation should not pose a danger in terms of the release of fumes harmful to human health or other environmental pollutants.
- For those who are going to carry out thermal insulation work on their own, the clarity and simplicity of working with the material is important, which does not require excessive effort, special experience, or special equipment.
- Finally, important criterion for anyone building material, including for insulation materials, there was and remains affordable price.
As you can see, the quality assessment criteria thermal insulation materials- so many. And now we will begin to “try on” them with insulation materials that are suitable for thermal insulation of a pitched roof.
What insulation can be considered the best for roofing?
This publication will mainly focus on the most widespread V private construction pitched roof. Flat roofs have their own specific thermal insulation properties, and the materials used for this purpose may be different. Thus, bulk insulation, special mortars with special filling, high-density mineral wool slabs and other materials are widely used. This issue requires a separate detailed consideration, so it will be omitted in this article.
And for pitched roofs, where on The insulation itself will not have a significant mechanical impact; they still try to use materials with a low specific gravity. They can be divided into three groups:
- Insulation with fiber structure.
- Rigid insulation with a gas-filled porous structure.
- Sprayed insulation.
These groups are also heterogeneous - materials can vary significantly in both basic composition and performance characteristics.
Insulation materials with fiber structure
This group of materials has one thing in common - they all represent an interweaving of thin fibers, due to which a layer of immobilized air is created enclosed in them. And this, in turn, becomes a thermal insulation layer. But the starting materials for the production of fibers can have serious differences, even down to their “nature” - mineral or organic. The first includes all types of mineral wool, the second subcategory includes cellulose-based ecowool.
Mineral wool
For thermal insulation of building structures in residential buildings, two types of mineral wool are used. In the first of them, fibers are formed from a melt of quartz glass, in the second, rocks of the basalt group serve as raw materials for production. Hence the names - glass wool and stone (basalt) wool.
There is another type of mineral wool - it is made from waste from metallurgical enterprises, slag. But it has not become widespread in residential construction, since it is inferior in both insulating qualities and durability. Yes and from the point of view environmental safety Not everything is all right with her either. In a word, there is no particular point in focusing your attention on it.
Prices for mineral wool
But you should take a closer look at glass wool and basalt wool.
Mineral wool based on glass fibers
For the production of glass wool, broken glass and purified quartz sand are used as raw materials. After the mass is melted in ovens, thin fibers are drawn out of it using a special technology, which are then pressed into “carpets” using binding additives. At the final stage of production, the products are cut into blocks or mats of standard sizes.
The production process has been worked out for a long time, there is also no shortage of raw materials, and therefore the cost of glass wool is quite affordable, which predetermines its wide popularity. The inlet form is blocks (slabs), mats in rolls, and recently, easy-to-install slabs in rolls have also been practiced.
TO dignity m of glass wool include the following:
— The specific gravity of the insulation is small, and therefore its installation does not require much physical effort, and the thermal insulation system does not exert a significant load on the roof structure.
— Glass wool blocks or mats have good elasticity. That is, they can be laid in spaces that are somewhat smaller in size - after straightening, they fit quite tightly to each other and to the enclosing elements (in this case, most often to the rafter legs).
“The same quality allows us to significantly reduce the volume of material when packaging it on the production line. This property allows you to reduce overhead costs for transporting insulation. And after removing the packaging, the blocks or mats, expanding, take on the specified dimensions.
— The material is flexible, that is, it can be used for thermal insulation of complex, for example, curved or broken areas without additional cutting into smaller fragments.
At the same time, glass wool also has certain flaws which must not be forgotten:
— This insulation has a fairly high hygroscopicity. Therefore, when using it Special attention addresses the creation of a reliable vapor barrier from the attic side, and the possibility of free evaporation of moisture from the roof side. Otherwise, the insulation will quickly become damp and lose all its thermal insulation qualities.
— Glass fibers are quite fragile. This means that vibrating effects are completely contraindicated for glass wool. Small broken particles of fibers become a serious irritant to the skin, eyes and mucous membranes of the respiratory system, that is, thermal insulation work should be carried out in compliance with special measures protection. Measures should be taken to completely eliminate the possibility of these particles entering the atmosphere of the living area of the house during operation, as they cause allergic reactions.
— The emission of formaldehyde, which is part of the binders, is also one of the disadvantages of the material. But this is more typical for cheap insulation materials of unknown brands (or even those that do not have any brand name at all - this happens too!) Leading manufacturers are trying to reduce emission rates to nothing, and many modern types of glass wool are approved for use not only in residential and public premises , but even in educational and medical institutions.
A few more words can be added about the “branding” of glass wool. The fact is that the construction market is filled inexpensive materials of very dubious origin. In the production of such glass wool, either outdated technologies are used, or the process of technological control is completely absent. Such mats are characterized by high fiber fragility and strong shrinkage, and glass wool can turn into dust in just a few years. Naturally, there can be no question of any quality of thermal insulation of the roof here. So the pursuit of cheapness often results in considerable additional costs.
If you have already decided to use glass wool for roof insulation, then you should pay attention to quality products, for example, from the companies Ursa or Isover.
For example, let's take a closer look at the insulation from the line « UrsaGeo". For roof insulation from this series are suitable « A private house» , "M -11" And "Pitched Roof", whose name speaks for itself.
The basis of all these materials is glass fiber with the addition of special mineral components that reduce the disadvantages characteristic of glass wool. Products from this range are considered completely safe for both humans and the environment.
The products of the Ursa company are characterized by a number of special advantages:
— The material belongs to the group completely non-flammable insulation materials. Not only does the insulation not ignite on its own, it can become a barrier to the spread of flame.
— The company’s technologists managed to reduce the emission of binding organic compounds to such a low level that it can not be taken into account at all - it does not in any way affect the cleanliness of indoor air.
“Thanks to special mineral additives, which are the company’s technological secret, the glass fibers received additional elasticity, that is, it was possible to reduce their characteristic fragility.
— In many types of thermal insulation “Ursa Geo”, in particular, in “Pitched roofing”, it is used interesting technology"URSA Spannfilz". This expression can be literally translated as “elastic felt.” The special structure of the fiber board gives it increased elasticity, and the insulation blocks fit very well between the rafters, which makes it possible to do without even additional fastening. And the tight fit eliminates the formation of voids, unfilled with insulation.
— Insulation materials are produced in a form that is very convenient for installation. For example, the “Pitched Roof” material consists of slabs in a roll, which greatly simplifies cutting in right size, if necessary.
— The manufacturer guarantees long term correctly laid thermal insulation without loss of its insulating qualities, without shrinkage and destructuring– at least 50 years.
The main characteristics of fiberglass insulation from the Ursa Geo line, which is excellent for thermal insulation of a pitched roof, are given in the table.
| A private house | M-11 | Pitched roof | |
|---|---|---|---|
| Thermal conductivity coefficient, W/m×°С | 0,045 | 0,044 | 0,040 |
| Vapor permeability, mg/m×h×Pa | 0,65 | 0,64 | 0,64 |
| Fire safety class | KM0 | KM0 | KM0 |
| Flammability group | NG | NG | NG |
| Operating temperature range, °C | 60÷+220 | 60÷+220 | 60÷+220 |
| Water absorption in 24 hours, kg/m², no more | 1 | 1 | 1 |
| Release form | mats on a roll | mats on a roll | slabs in roll |
| Dimensional parameters, mm | |||
| - length | 8350 | 7000; 9000; 10000 | 3900; 3000 |
| - width | 1200 | 1200 | 1200 |
| - thickness | 50 | 50; 10 | 150;200 |
| approximate cost | 1100 rub/m³ | roll 1200×10000×50 mm - 1220 rub. | 980 rub. with a thickness of 150 mm; 1070 rub. with a thickness of 200 mm. |
Basalt-based mineral wool
Fibers obtained from molten rocks gabbro-basalt groups have a number of advantages over glass ones. They become thinner and longer, they have more elasticity and much less fragility. All this gives mineral wool on this basis higher performance qualities. All the advantages inherent in glass wool are also inherent in basalt wool, and there are, in addition, a number of advantages.
Prices for basalt wool
basalt wool
It is even visually noticeable that high-quality basalt wool has a clearly homogeneous structure; it is given clear geometric shapes. It is much easier to work with such insulation - it is certainly not worth neglecting skin and respiratory protection, but it does not cause as much irritation as glass wool.
Basalt wool is also better at being hygroscopic - special treatment sharply reduces moisture absorption, and the products of some manufacturers even have properties close to hydrophobicity. But this still does not give grounds to refuse vapor barrier. Vapor permeability is high, that is, when the necessary conditions are created, even moisture that accidentally penetrates into the material will easily evaporate through the ventilation gaps of the roofing pie.
Products famous brands Everything is going well with formaldehyde emission indicators - insulation materials have sanitary certificates with approval for safe use in any residential premises. By the way, it would never be a bad idea to check for a copy of such a certificate when purchasing any insulation material.
Basalt wool slabs are extremely easy to install - both due to their precise “geometry” and due to their pronounced elasticity. And besides, manufacturers provide other “chips”. For example, “ROCKWOOL LIGHT BUTTS SCANDIC” slabs, popular among builders, have an edge “spring-loaded” using a special technology, which ensures their precise and reliable fixation at the installation site - between rafters, beams,
Perfect solution for roof insulation - ROCKWOOL LIGHT BUTTS SCANDIC slabs with a springy edge zone, which makes installation simple and very reliable Basalt wool has few significant disadvantages (if we are talking about really high-quality products from well-known brands). Perhaps this can only be attributed to the higher cost of the material.
The range of basalt insulation materials is quite wide. Along with the “heavyweights” in this area of production - the companies ROCKWOOL, PAROC, TechnoNIKOL, the companies Basvul, Isobel, Izovol and others offer quite worthy products. Before purchasing, it makes sense to take a closer look at the brand you like - trustworthy companies always have informative Internet portals, and a network of representative offices has been organized throughout Russia.
As an example to familiarize yourself with the physical and operational characteristics, you can take the already mentioned above insulation “ROCKWOOL LIGHT BUTTS”. By the way, another advantage is that during packaging in production it is compressed by more than half due to vacuum technology. But when the packaging is removed, the slabs take on the specified dimensions without any loss of their performance.
| Name of the main operational parameters of the material | Indicators |
|---|---|
| Thermal conductivity coefficient (W/m×°C): | 0,039 |
| Specific gravity (kg/m³) | 30 |
| Flammability group | NG |
| Fire safety class | KM0 |
| Vapor permeability (mg/(m×h×Pa), not less | 0.03 |
| Moisture absorption when partially immersed | no more than 1kg/m² |
| Dimensions | 800 ×600 mm (XL slabs - 1200× 600 mm) |
| thickness | 50 or 100 mm (XL slabs - 100 and 150 mm) |
| approximate cost | - with a thickness of 50 mm - 145 rub./m² - 100 mm - 285 RUR/m² - 150 mm - 430 rub/m² |
The service life of such thermal insulation is estimated at no less than 50 years.
Organic-based fiber insulation – ecowool
This insulation appeared in widespread use not so long ago, and is even unknown to many. Meanwhile, it shows very good thermal insulation qualities.
The basis for the production of ecowool is ordinary cellulose fibers obtained from wood waste, paper and other waste raw materials. The total cellulose content in this insulation reaches 80 ÷ 85 percent. The rest is additives that ensure the biological resistance of the material (boric acid) and special flame retardants that increase the resistance of cellulose to fire.
Thermal performance indicators of ecowool are very decent: the thermal conductivity coefficient is approximately in the range from 0.038 to 0.043 W/m×° WITH, that is, quite comparable to mineral wool.
The material is famous for its environmental cleanliness (hence its name), and antiseptic treatment reliably protects it from decay and decay, and from damage by pathogenic microflora. Rodents and insects do not make nests in ecowool.
According to the degree of flammability, the material belongs to group G 2 - low-flammable, self-extinguishing. Combustion products do not contain toxic substances, which is typical, for example, of synthetic insulation.
Ecowool is quite hygroscopic, so issues of reliable hydro- and vapor barrier will definitely have to be thought through. But due to the capillary structure natural fibers, moisture also easily evaporates from the material without disturbing its qualities. Interestingly, in this way, ecowool insulation stands are able to “automatically” maintain optimal humidity balance in the room.
Prices for ecowool
Ecowool is laid using “dry” and “wet” technologies. But application by the “wet” method, that is, by spraying, is not particularly justified on roof slopes that have a negative slope on the attic side - there will be too much waste. Therefore, most often this insulation is blown into cavities that are created using vapor barrier membranes or the internal lining of the attic.
Insulation of roof slopes with ecowool - the material is blown into the created cavities using a special installation The density of the insulating layer, depending on the application method, ranges from 40 to 75 kg/m³.
TO shortcomings Similar insulation includes the following:
— Even the “dry method” of laying ecowool (with the exception of floor insulation) requires a special installation. In addition, for high-quality execution Such work requires well-developed skills.
— The process of laying ecowool is very dusty in any case. You cannot start it without personal protective equipment.
The cost of ecowool ranges from 20 to 35 rubles per kilogram. Usually she comes on sale in sealed plastic bags, packaged in 15 or 20 kilograms.
It seems - not so much. But if you look at the price lists of services provided by manufacturers or distributors of such insulation, you will see that you will also have to pay approximately the same amount for installation. And without special equipment it is extremely difficult to do this. This, perhaps, is the most important “minus” of such thermal insulation.
Sprayed insulation
One of the most effective ways to insulate a roof is to spray foam insulation on the back side of the roof slopes. With this approach, the thermal insulation layer becomes almost seamless, that is, without leaving cold bridges.
There are several types of such materials. But the closest thing to “ideal” in terms of all criteria for thermal insulation quality is polyurethane foam.
Perhaps the most reliable and effective method thermal insulation of pitched roofs - spraying polyurethane foam The thermal conductivity coefficient of polyurethane foam is very low, estimated at less than 0.03 W/m×°C. The material shows excellent adhesion to almost all surfaces. A closed cell makes the insulation layer vapor-tight, which means that in some cases you can do without additional costs for vapor barrier.
However, all the advantages of the material are also combined with quite at a high price on him. Moreover, polyurethane foam is synthesized directly on site from two initial components, for which special installations are used. That is, “lovers of independent creativity”, one way or another, will have to resort to calling a brigade. And this also costs a lot of money.
There is, however, a caveat - disposable mini-installations for spraying polyurethane foam have recently appeared in construction stores. However, their price is no lower than the cost of professional services.
If you look at the price lists of construction companies in the Central region of Russia, the cost of spraying polyurethane foam 100 mm thick on an area of 1 m² ranges from 1100 to 1400 rubles, depending on the manufacturer of the initial components. Agree, it’s very expensive.
We can talk a lot about polyurethane foam, but we will limit ourselves to the brief information given above. The fact is that on our portal a special publication is devoted to this type of insulation. By the way, it also talks about another type of foam insulation - penoizol, which can also be used for thermal insulation of roofs.
Prices for polyurethane foam
polyurethane foam
Special thermal insulation technology - foam insulation
These differ from all other insulation materials, first of all, in their special application technology. Read about the advantages and disadvantages and the features of working with them in a special article on our portal.
Synthetic-based rigid insulation boards
Polystyrene based materials
This group of insulation materials includes the familiar white foam and extruded polystyrene foam. Despite the relatedness chemical composition, difference in performance qualities of these materials is very large.
- Let's start with foam. And here we will immediately express a categorical judgment, with which some may not agree. However, using foam plastic for thermal insulation of roof slopes is extremely undesirable.
There are no words - foam plastic captivates with its low price, quite decent thermal insulation characteristics, lightness, and ease of installation. What more could you want?
But let's take a closer look at its shortcomings:
— The production of polystyrene foam is a fairly simple process that does not require highly complex equipment. And they do this business everywhere, very often without complying with any technical requirements. So talking about any quality standards is simply ridiculous.
— The main disadvantage of polystyrene foam is its flammability. And this material not only spreads flame very well, but also emits deadly toxic substances when burning. Literally a few breaths - and a person receives powerful poisoning, leading to the most tragic consequences. Statistics of fire tragedies show that if polystyrene foam catches fire, people have little chance of surviving even in a not very large fire. Is it worth planting such a “bomb” on such a vulnerable part of the building from the point of view of fire danger as the roof?
Prices for PIR boards
The main component of such boards is polyisocyanurate foam (abbreviated as PIR). It is a gas-filled rigid structure with isolated cells.
Thanks to the special production technology and the specifics of the polymer itself, insulation boards are still considered unsurpassed for its thermal insulation qualities. Thus, the manufacturer claims an absolutely fantastic thermal conductivity coefficient of 0.022 W/m×° WITH! In reality, in real conditions, it may, of course, be more, but even 0.025 is a very good indicator.
The material has high mechanical strength - up to 120 kPa at 10% deformation. At the same time, the density of the slabs does not exceed 40 kg/m³
Wide operating temperature range: from – 70 to + 110 °C.
Almost complete hydrophobicity – closed cell prevents moisture from penetrating inside.
PIR boards can be covered with foil, which gives them additional slickness against moisture. Other types of coatings are also practiced.
Many slab models have convenient tongue-and-groove locking connections, allowing large areas to be covered with a seamless coating.
One of the “pioneers” in the production of such thermal insulation was the Russian company Technonikol. Its product range includes slabs for insulating any areas of the building, including the roof. At the same time, the company offers ready-made solutions– sets of materials for thermal insulation of the roof between the rafters, under them and on top of them – at the choice of the consumer.
Standard sizes watering - 600×1200 mm. The thickness is selected according to need - there is a range of slabs with a thickness from 25 to 150 mm.
There is no doubt - such thermal insulation materials have a great future. But so far they have not become widespread - simply because of the high cost. So, depending on the specific type, on the type outer covering and depending on the thickness of the slabs, their price varies from 11 to 15 thousand rubles per cubic meter.
TechnoNIKOL is not the only company that has mastered the production of these innovative materials. Watch a video about the insulation of a pitched roof with PIR boards from the company " PirroGroup."
Video: Insulation of roof slopes with innovative thermal insulation - PIR-boards “PirroGroup”
Appendix: How to determine what thickness of insulation is required?
If there is certainty with the choice of insulation, then the question will inevitably arise - what thickness of thermal insulation should be made to ensure comfortable conditions in the attic. We will need to make a small calculation, and a convenient online calculator will help us with this.
The calculation is not particularly complicated. The algorithm is based on the fact that the thermal insulation system being created must create a total resistance to heat transfer no less than that established by the standards for a particular region, taking into account its climatic features. Find out normalized thermal resistance You can use the attached diagram map. Please note that in this case we are interested in the red numbers - for coatings. This figure in the “three” is always the largest.
The second quantity required for calculation is the thermal conductivity coefficient of the insulating material. Already included in the calculator database operational values these coefficients for insulation materials, about which discussed in this publication.
If desired, you can also take into account the lining of the attic space, if it is solid. The materials of such cladding also have certain thermal insulation qualities. And this can, although not particularly large, still reduce the required thickness of the insulation. However, this item is optional, and if the skin is not taken into account, simply leave its thickness at the default value of 0 mm.
The final result will be shown in millimeters. All that remains is to lead him to standard thicknesses selected insulation, rounded up. For example, it turned out to be 132 mm. You can use two-layer insulation with slabs 100 and 40 mm thick, or use slabs 150 mm thick. Here you can already choose for reasons of economics of one or another possible option and according to the planned insulation installation scheme.
Heat loss in the cold season, 15–20% of total heat loss reaches through the roof.
This means that if the floor and walls are well insulated, but the ceiling or roof is not insulated, then with total heating consumption 2000 kg of coal per season, 300–400 kg is spent on heating the street.
Thus, with an insulated roof, it will be possible to buy 1600–1700 kg of coal per season instead of two tons.
However, the matter is not limited to saving money. Roof without thermal insulation heated by warm air from below. Snow falling on a warm roof melts and sticks to it in a thick layer. This increases the stress on the roofing material and can lead to damage. During a thaw, a layer of snow melts from below and slides off the pitched roof, damaging the drainage system.
Roof with good thermal insulation stays cold. Dry snow is blown away from it by the wind, practically without stopping. There are almost no icicles on the edges of such a roof.
Obviously, the difference is significant enough to consider insulating the roof. This kind of work does not require highly qualified , so with certain knowledge and skills you can do it yourself.
You can insulate the roof from heat from below during its installation. This is what they usually do now. Work in this case are carried out from above in this order:
- A vapor barrier membrane is attached to the lower surfaces of the rafters. To do this, the panels are unfolded and, slightly stretched, stapled with a stapler. Work begins at the bottom of the rafters and ends at the ridge. The panels overlap at the joints, gluing the edges with construction tape.
- From below, the vapor barrier film is nailed to the rafters with bars with a cross-section of 30×40 mm across the rafters in increments of 30–40 cm. This lathing will hold the insulation, and the finishing material is attached to it from below.
- Insulation boards are laid on top between the rafters to the level of the top edge.
- When the slabs of heat-insulating material are level with the upper edge of the rafters, they are covered with panels of waterproofing, vapor-permeable material. This hydrobarrier is secured with staples using a stapler in the same way as a vapor barrier with an overlap of 15 cm.
- A sheathing is constructed on top of the hydrobarrier, onto which the roofing material is secured.
However, for one reason or another, insulating materials are not always installed together with the roof. In this case the roof have to insulate later. The same is done in old houses after renovation.
Do-it-yourself insulation of a finished roof in a private house
Laying thermal insulation into an already constructed roof happens in reverse order. If the insulation “pie” during construction is formed from above, then finished roof insulated from below.
Before work starts need to find out how well the roof is installed.
In an old house need to check strength of rafters and floor beams. Rotten load-bearing elements are replaced with new ones, treated with preparations that protect against rotting and fire. After this, they begin laying thermal insulation:
- After measuring the thickness of the rafters and the distance between them, the sheets of thermal insulation material are cut with a slight excess in width (about 1–2 cm). This is necessary so that the elastic plates fit into place tightly, without gaps.
- A hydraulic barrier is needed between the roof and the insulation, protecting against water drops but allowing steam to pass through. If the roof is new and was installed according to all the rules, you will not have to lay it. Otherwise, you will have to purchase waterproofing. The best candidates for this role are the so-called superdiffusion membranes, do not allow liquid water to pass through, but at high air humidity they allow water vapor to pass through. This material is laid without undue tension and secured with a stapler to the rafters, and in the spaces between them - to the roof sheathing. The panels at the joints are secured with an overlap of 15 cm, gluing one panel to another with construction tape.
- Cut slabs of thermal insulation material are inserted between the rafters, pressing them against the membrane. All cracks that arise are sealed with construction foam. It is preferable to lay the slabs in two layers, overlapping the joint of the previous layer with the slab of the next one. After completing this stage, the level of the slabs should be equal to the inner end of the rafters.
- Along the inner end of the rafters it is stretched and secured with a stapler. The panels are unfolded horizontally and laid from bottom to top with overlapping edges of adjacent panels 15 cm wide. The edges are glued with construction tape.
- On top of the film, at right angles to the rafters, sheathing bars with a cross-section of 30×40 mm are stuffed in increments of 30–40 cm. The lining or fiberboard slabs will be attached to them. After completion of work between vapor barrier film and finishing creates a ventilation gap to evaporate possible condensation.
- The more carefully the vapor barrier is laid, the better the insulation retains heat.
Flat roof insulation
Flat roof too can be insulated. However, in this case there is no attic. External insulation of such a roof is done during the process of laying the roof. A vapor barrier film is glued to the floor slab.
Insulation is laid on top of this film. The best thing suitable for these purposes. After laying, the top of the stone wool is covered with roofing felt, which serves as a vapor-permeable waterproofing.
So that you can walk on the roof, without damaging the roofing material, the covering is done in the same way as on the sidewalk. To do this, a layer of expanded clay is poured onto the roofing felt, then a cement-sand mixture is placed on which paving slabs. After getting wet in the rain, the cement-sand mixture sets and holds the tile.
Expanded clay underneath plays the role of drainage. There are no ventilation layers in such a roof. Internal insulation of a flat roof is done using the technology of internal thermal insulation of the ceiling.
So that living conditions in winter are quite comfortable, it is necessary to ensure a certain level of thermal insulation of the room. This level is determined by heat transfer resistance. It doesn’t matter how many layers and what kind heat-insulating material packed.
How to do the calculation required thickness insulation, you can read in the article “”. If you correctly lay thermal insulation materials when installing the roof, you can save 15–20% energy, spent on heating a private house.
The technology of roof insulation is simple. Any home handyman can handle it subject to technology. You can insulate the roof during the installation of the roof and after it. However, the technology for carrying out such work will be different.
For detailed instructions from ISOVER on how to insulate a roof in a private house with your own hands, watch the video:
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 classic version The layers of the pie, starting from the finishing roofing, are placed as follows:
- roofing;
- lathing for installation 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?
On modern market There is 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 and resistant to any adverse external influences. roofing system. It’s better to immediately do everything according to the rules and live peacefully in safe home than patching holes in 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 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 in 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 according to the instructions, and very soon your home will become truly cozy and warm, and heating costs during the cold season will be significantly reduced.
Good luck!
Video - Do-it-yourself roof insulation from the inside
The huge space under the roof of the house is now being turned not into a warehouse, but into a comfortable and spacious living space. But in order to keep the attic warm in winter and cool in summer, it should be insulated in accordance with the technology. We will help you choose a budget-friendly, durable and easy-to-use heat insulator and familiarize you with the nuances of its use.
The building materials market offers many options for thermal insulators, but sellers usually talk only about the advantages of the material and rarely warn about the disadvantages. Therefore, it is important to understand which material and in which situation will be more preferable.
The effectiveness of insulation differs greatly: a more modern material can have tens of times less thickness with the same thermal insulation ability
The “correct” insulation must meet the following requirements:
- easy to install (since the roofs in our region are pitched rather than flat, preference is given to materials that can be held on an inclined surface);
- be safe to install and use (for example, glass wool chips unpleasantly during installation, and polystyrene foam releases carcinogens when heated);
- do not support combustion (since the main structure of the roof is made of wood, the use of flammable insulation can lead to rapid destruction of the house);
- be lightweight (any heat insulator is an additional load on the roof structure, walls and foundation);
- differ in small thickness (the larger the layer of heat insulation, the lower the height of the ceiling in the attic).
Polystyrene foam is one of the most popular thermal insulators because it is one of the cheapest. The slab material is easy to transport and install, does not overload the roof structure, and is completely unaffected by moisture, so it is not afraid of rot and mold.
Polystyrene foam is the best option for external insulation, so it is worth choosing if the roof of your house is flat. It will help to insulate the roof without losing internal space. If you bought the attic above your apartment in multi-storey building, then you can increase its height from 2.2–2.3 to 2.5–2.6 m only by transferring the heat insulator to the outer layer. True, for this you will have to agree on similar work with other residents top floor or with the management company.
This material is quite dense, it is not afraid of water, so builders also use foam plastic for thermal insulation of floors. Expanded polystyrene slabs are poured into the screed when arranging the floor in the attic.
You'll have to spend a lot construction foam to process all the cracks
However, when internal insulation the roof between the rafters reveals the disadvantages of foam plastic:
- the slabs are not elastic, so there are gaps between them that need to be filled with foam;
- expanded polystyrene interferes with the ventilation of rafters and other wooden frame elements, which can lead to their destruction by rot or fungus;
- polystyrene foam has a fairly low degree of sound insulation, so if it is important for you to cut out unnecessary sounds, it is better to choose less dense insulation;
- if the thickness of the material is incorrectly calculated, the dew point ends up inside the insulated space and the heat-insulating cake begins to collapse;
- modern foam plastic does not support combustion, but melts when high temperature and releases toxic substances, so if a stove or fireplace pipe passes through the attic, it is better to insulate the space around it with another material.
In addition, polystyrene foam is unpleasant for many to work with, since when cutting and rubbing with hard surfaces it makes repulsive sounds (a similar reaction is caused by the grinding of metal on glass).
Use polystyrene foam for external insulation of facades, roofs, ceilings and protect it from atmospheric influences. Only in such a situation will expanded polystyrene provide reliable thermal insulation and not show its shortcomings.
By the way, when installing a green roof with grass and ornamental plants, foam plastic is used for thermal insulation, because it does not deform under the weight of subsequent layers of drainage and soil.
A green eco-friendly roof is not only beautiful, but also very warm, because there is foam underneath it
Roof insulation with penoplex
From a chemical point of view, Penoplex is a new generation of polystyrene foam. This material is produced in the form of hard orange slabs with no visible granules. What distinguishes it from the usual expanded polystyrene:
- tongue-and-groove edge, which helps to join the slabs without gaps, so there is no need to foam the seams and then trim the foam;
- more high density, thanks to which the roof increases resistance to snow loads;
- homogeneity, due to which the slab does not crumble when cut;
- lower thermal conductivity, which allows you to reliably insulate the slope with a 2 times smaller layer of insulation and maintain the ceiling height in the attic.
From its older brother, penoplex inherited water and steam resistance, immunity to the influence of fungi and bacteria, the ability to serve for a long time and the absence of dust when cutting. It can also be installed in any weather and humidity level. It is allowed to install penoplex without insulating membranes.
When the roof is insulated with penoplex, the roofing pie may not contain a hydro- and vapor barrier film
But despite all the efforts of the manufacturer to rid the material of flammability, the polymer remains dangerous in case of fire. Of course, it will not ignite on its own and will not burn without direct contact with fire, but the smoke released during melting can poison the residents of the house.
Video: roof insulation technology with penoplex
Polyurethane foam is also a close relative of polystyrene foam, but unlike the latter, it is not sold in finished form. The chemical reaction that creates the polymer pimples already takes place on your roof, so polyurethane foam is guaranteed to fill the smallest gaps between the rafters. In addition to providing a uniform, seamless coating, the material has other advantages:
- high thermal, hydro and sound insulation without cold bridges with a moderately thick layer of material, which allows you to maintain the height of the ceiling (the final thickness is three times less than when using polystyrene foam or cotton wool);
- no need for additional work (installation of fasteners, sheathing), dust removal and surface priming are sufficient;
- fire safety (the material does not support combustion, does not melt at temperatures up to +220 o C);
- suitable for the northernmost regions ( normal temperature operation down to -150 o C);
- not afraid of fungus and rot.
Experts note that if the material is protected from ultraviolet radiation, polyurethane foam insulation can last more than 30 years.
You can insulate the roof with polyurethane foam not only inside, but also outside
What don't sellers tell you? For example, that polyurethane foam should absolutely not be applied directly to the roofing material or the membrane adjacent to it. Since the foam sticks tightly to the base, it becomes impossible to create the ventilation gap necessary for these materials, and the roof covering is slowly destroyed. Of course, you can line the slope with membrane-protected boards or OSB boards at a short distance from the main covering and apply foam to this covering. But such events will inevitably lead to an increase in the cost of the project, so some craftsmen prefer not to mention the nuances when talking with homeowners.
Insulation with polyurethane foam is impossible without special equipment, so when comparing materials, take into account the costs of the work of craftsmen. While laying polystyrene foam or cotton wool can be done with your own hands, you definitely won’t be able to spray polyurethane foam yourself.
If we take into account all the requirements of the technology, polyurethane foam turns out to be a very good choice for all types of houses and roofs, because it is not without reason that in Europe and the USA it is considered the most popular thermal insulator.
Video: how polyurethane foam is sprayed
Roof insulation with mineral wool
In our region, mineral wool is most often used to insulate pitched roofs. One of its main advantages is ease of installation. The technology is so simple that with its help even one adult with a teenage assistant can insulate a stingray. But mineral wool can be different:
- glass (glass wool). It is excellent for insulating heated elements (for example, stoves and fireplace pipes), as it can withstand heat up to 450 o C. In addition, cotton wool insulates extraneous noise and quickly restores its shape after shock and vibration. One of the main disadvantages of glass wool is its flowability. While working with it, the master runs the risk of inhaling a huge amount of tiny fragments of glass fibers, and if cotton wool gets on the skin, the hands and feet begin to itch and turn red (this is not an allergy, but microscratches). As a result, installation must be performed in overalls and a respirator, which makes the process long and uncomfortable;
Glass wool releases tiny particles of fibers interspersed with glass, which unpleasantly scratch exposed skin.
- stone (basalt wool). Stone wool is more resistant to moisture, does not cake as quickly and holds its given shape longer. Therefore, there is no need to fear that the heat insulator will slide down the slope over time. In addition, mount basalt wool can be done without personal protective equipment, it is safe for health and practically does not cause itching.
Basalt wool is easily distinguished by the brown-brown color of its long strands
Both types of wool are available in the form of mats of several sizes and in rolls. If the roof is simple and it is possible to adjust the sheathing pitch (and cell size) to the parameters of the mat, it is best to use soft slabs that will themselves be held in the cells. For roofs with complex slopes, overhangs and bay windows, it is better to buy rolled cotton wool, although it will require additional fastening.
Mineral wool is an effective material, but capricious to use. In particular, it should be protected from moisture from above and steam from below, as well as natural ventilation. Such requirements will result in additional costs for hydro and vapor barriers, and the work will take longer due to the construction of another sheathing.
Do not skimp on insulation by violating the mineral wool installation technology. It’s better to properly insulate with cheap cotton wool than to leave expensive ones without ventilation.
Those who ignore the rules, after the first autumn, can admire the wet, rotting insulation and unpleasant cold in the attic. And if the situation is not corrected, over time the rafters will begin to rot.
Video: roof insulation with mineral wool
If you see soft snow-white insulation in a store, this is not know-how, but a variation of mineral wool made from quartz sand with acrylic binder. Studies have confirmed its safety for health, which is why it is recommended to use this type of wool to insulate an attic if you plan to make a children’s room in it. In addition, white glass wool holds up better when installed by surprise, does not smell and is not prone to dust, so the installation process is much simpler than installing ordinary brown glass wool.
Quartz wool is most often produced in rolls and is the safest type of mineral wool for health.
Roof insulation with ecowool
An even safer and more natural analogue of mineral wool is cellulose ecowool. This material is available in slabs or in the form of loose fibers, slightly reminiscent of fluff. Among the advantages of ecowool:
- natural composition;
- combustion resistance (class G2);
- good resistance to rotting, insects, rodents and fungi (treated with safe impregnants - brown or boric acid);
- preservation of properties when wet;
- high degree of thermal insulation (4 times higher than expanded clay);
- environmental friendliness. Does not cause allergies during installation;
- formation of a seamless layer of thermal insulation;
- frost resistance.
Ecowool is available in different modifications, and the higher its class, the more similar it is to medical
Table: comparison of characteristics of basalt and cellulose wool
The only disadvantages of ecowool are the need for vents to ventilate the material and difficulty in installation. It is better to spray cotton wool in the form of fluffy fibers using a blowing machine, but if you have time and are not inclined to save on the amount of material, this can be done manually. This is the only cotton wool that can be wetted for ease of installation.
Among the natural analogues of mineral wool, one can also note teplolen (slabs made of flax fibers), but in appearance, characteristics and installation features it is not very different from mineral wool.
Roof insulation with expanded clay
Expanded clay (foamed clay granules) attracts attention with the following properties:
- environmentally friendly (it consists entirely of mineral components without the addition of polymer resins and other popular binders);
- resistance to mouse teeth (it simply does not attract the interest of rodents, who happily make nests in mineral wool and polystyrene foam);
- long service life (50–60 years is not the limit for expanded clay);
- extremely low thermal conductivity (a layer of 10 cm of expanded clay insulates heat like 25 cm of timber or 100 cm of brick).
At the same time, the cost of the material is not exorbitant; it is considered one of the most budget-friendly insulation materials.
This is what a roof insulated with expanded clay looks like in section
- The slopes are hemmed from the inside (with OSB boards, fiberboard, clapboard).
- A membrane is laid on top.
- A layer of expanded clay (14–16 cm) is poured onto it and leveled.
- Lay waterproofing.
- Install the sheathing, counter-lattice and roofing material.
It is almost impossible to properly insulate a finished roof with expanded clay.
Expanded clay granules are fragile, try not to damage them when filling.
Foamed roll insulation for roof
Among the roll insulation for roofing, there are also fully polymer ones available, which look like a substrate for a laminate. In most cases this is:
- penofol (foamed polyethylene) with a layer thickness of 3–10 mm, which can be supplied with single- and double-sided foil and an adhesive layer;
- penotherm (foamed polypropylene) 6–10 mm thick, with or without foil.
Products with similar properties and composition are also produced by the brands “Izolon”, “Alufom”, “Polifom”, “Jermaflex”, “Ekofol” and others.
Foam insulation is so thin that rolls for the entire roof can be brought in a car
These materials are extremely thin, but in combination with foil they can provide reliable thermal insulation of the attic. Their light weight and thin thickness make them great for owners of older homes who are not ready to reinforce the roof and foundation structure. Foamed polymers are completely safe during installation, and thanks to the coating made of pure aluminum, they are not able to emit any harmful substances into the atmosphere of the attic. The material simultaneously serves as heat, moisture and sound insulation; no films or membranes need to be installed with it. Penofol is also used when the ceiling height is critically low. To maintain the height of the attic, you don’t even need to cover it with finishing; the foil ceiling will look unusual and futuristic.
At the same time, penofol and penotherm can be used in combination with any other types of insulation, from mineral wool to fiberboard. Such a multi-layer cake will improve your thermal insulation several times, and foam insulation costs no more than a good waterproofing membrane.
When using penofol instead of a membrane, the efficiency of mineral wool increases noticeably
The only drawback of foamed heat insulators is their low heat resistance; they begin to collapse when heated to 91 o C.
Roof insulation with wood fiber boards
Previously, ceilings and floors were insulated with a mixture of sawdust with the addition of cement. Fibrolite is a more modern variation of this technology, but it has also been known for a long time. There were more than 40 factories producing this material in the USSR. Unlike chipboard, with which it is sometimes confused, fiberboard is not made of shavings, but of longer wood fibers (which resemble straw). In addition to them, the slabs contain Portland cement and liquid glass, therefore this material is less flammable, heavier and is not afraid of moisture, like chipboard.
Fiberboards can serve both as insulation and as a base for finishing(painting or putty)
Now fiberboard is not considered insulation; it is more often used for cladding the frame of a house, constructing partitions and continuous roof sheathing. But at the same time, fiberboard boards have a low thermal conductivity coefficient, so they are used for insulation both on their own (usually in two layers with offset sheets) and in combination with softer insulating materials (mineral wool, ecowool). Moreover, it is suitable for all types of roofs (flat, single, gable, complex). Unlike other types of heat insulators, fiberboard can be puttied, painted and wallpapered, which greatly simplifies the finishing of the room.
A distinctive property of these wood-fiber boards is their excellent thermal stability. For example, mineral wool under a metal tile on a summer afternoon will heat up in 2 hours, but fiberboard will not change the temperature for 10 hours. The material is so heat-stable that it can be used to build fused roofs (roofing felt, bitumen shingles) using open-flame burners.
Which insulation is best to use for a private home?
In private houses, the roofs are usually pitched, so when insulating it is better to focus on soft materials, leaving polystyrene foam and penoplex for external insulation flat roofs. The final choice depends on the roof configuration and finishing material. For example:
When purchasing insulation, be sure to ask your consultant whether the type you have chosen is suitable for roofing, since wool, polystyrene foam, penoplex and other materials for roofs, walls and ceilings differ in density, size, thickness of the slabs and other characteristics. Take the time to read the information on the packaging - most manufacturers indicate the purpose of the material.