Making the attic a living space is not an easy task, but the result will allow you to get a lot of positive emotions. In order for your attic to become a living space, it must be thoroughly insulated, otherwise all the heat will practically fly out into the street. The process itself directly depends on at what stage of construction you decided to make the attic residential.
We insulate the attic with mineral wool
The best option for insulating the roof and walls of the attic is the construction stage, at which it is still possible to lay the materials into the roof. However, much more often it is necessary to remodel the existing attic into an attic, and then insulate the room. In this case, it is necessary to thoroughly consider the options for wall and floor insulation. Do not forget about the heating system necessary for the attic in winter.
Photos of heating radiators
To insulate the walls and roof of the attic with their own hands, they use a variety of insulation materials, such as:
- Styrofoam;
- expanded polystyrene;
- mineral wool;
- ecowool and others.
According to their characteristics, they have a slight discrepancy, let us consider in more detail the use of mineral wool and ecowool for these purposes.
Is it possible to insulate the attic PPU
The presence of the attic already indicates that its insulation is required. It is foolish to have a second floor and not use it to expand living space. Even if it is not supposed to live in these rooms in winter, you still cannot do without this procedure. Heat from the lower floor tends upward. If the roof is not insulated, condensation forms when it encounters cold air. The attic will be constantly wet, fungus will appear, the wooden elements of the rafters will quickly rot.
The properties of polyurethane foam determine the material as an excellent insulation for the attic
With regard to polyurethane foam, we can say that this is an ordinary polyurethane foam, only for such works it is used in large volumes. For the attic, PPU is considered an excellent choice. In a solidified state, the material forms many airtight pores with air, due to which the insulating properties are improved. Cured polyurethane foam is vapor and moisture resistant. He does not need steam and waterproofing. Due to the expansion, the PUF fills all hard-to-reach areas. Foam insulation is considered safe, since the material is environmentally friendly, not inclined to maintain combustion. All of these qualities meet the requirements for attic thermal insulation. It is safe to say that PPU is suitable for work.
A feature of the attic is the complex shape of the roof. The use of rigid slabs is not possible in some areas. Rolled materials slide off the slopes, the mineral wool is caked. A popular option for insulation is laying basalt slabs, but they must be protected from moisture on both sides with membranes. With polyurethane foam, everything is simple. Spray foam on surfaces of any complexity. Even on the fractures of the roof, a single sealed layer is formed.
Important! If the insulation is made with polyurethane foam, the attic stops "breathing". The effect of a thermos is created. Arrangement of ventilation will be required, otherwise dampness will form. 1-2 layers of polyurethane foam on the roof of the attic allows you to save up to 30% heat
In a non-residential attic, it is enough to spray a couple of layers of polyurethane foam, which will already save up to 30% of heat. However, it is important to know that UV foam breaks down. After warming, you will definitely have to fix the finishing sheathing, for example, lining.
Another nuance is the choice of insulation technology. PPU is of three types.Foam differs in hardness: soft, medium and high. The classical technology of insulation is based on the use of PU foam of the same rigidity. Polyurethane foam is sprayed in several layers. In complex technology, several types of foam are used, only the layers are sprayed alternately. Rigid PU foam is always used for the first layer. Its thickness is from 3 to 5 cm. Subsequent layers are sprayed from soft foam. Their thickness varies from 5 to 8 cm.
Requirements for materials for attic insulation - make a choice
- No harmful fumes... Since the attic is insulated from the inside, materials for this purpose must be taken environmentally friendly and safe. We discard styrene-emitting polystyrene and cheap stone wool, which many dishonest manufacturers pass off as basalt. This insulation is made from cheap raw materials, generously flavored with harmful phenol-formaldehyde resin.
- Low hygroscopicity (poor ability to absorb moisture). Natural ventilation occurs through the attic, so the material used to insulate it should not absorb water vapor. Therefore, we exclude all wool from natural materials, for example, ecowool, produced from wood and paper waste. Having used such material as a floor insulation in the attic, the owners in a couple of years will see pieces stuck together instead of it.
- Low thermal conductivity... The attic is exposed to high temperature loads, so a material with high thermal conductivity for insulation is not suitable - it will be cold in the room. In this position, polyurethane foam is clearly in the lead. The material keeps heat well, adheres firmly to the walls, adheres securely and does not get wet.
- Long service life... Few people like to disassemble the entire insulation "pie" every 5-6 years. We discard glass wool and its derivatives, the service life of which rarely exceeds 10 years. Fiberglass-based cotton wool should not be used also because it contains toxic impurities and "dusty" with small particles of glass. Due to harmful fumes, many firms refuse to lay glass wool, because after it dermatitis remains on the hands and the feeling of sand in the eyes. Harmful impurities are embedded in glass wool to protect it from rodents. But, as practice has shown, these tricks do not interfere with mice and rats, unlike people who inhale poisonous vapors.
- Simplicity of fastening... It is unprofitable to fence multilayer structures in the attic, since this significantly reduces the usable area of the room. For this point, polyurethane foam is also preferred. The material can be applied directly to the surface of the walls and floor of the attic. The maximum that is needed in this case is to put together a wooden crate of a small height, since polyurethane foam is applied in a layer of only 5-8 cm. For comparison, mineral insulation has a mats thickness of 10-15 cm, which is about 3 times more. Therefore, the loss of area when using them will be higher.
- Incombustibility... The attic has a large number of wooden elements, so a fire that has arisen, for example due to faulty wiring, in the presence of combustible insulation becomes a disaster. For this reason, we remove the foam from the list of possible materials. It flares up quickly and burns easily, giving off a poisonous gas that is easy to suffocate.
Pros and cons of foam attic insulation
To find out whether insulation will be beneficial, it is necessary to consider all the subtleties of the technology, to identify the pitfalls. It should be noted right away that costs are relegated to the background. For the home budget, this is a big minus, but the goal is to reliably insulate the roof of the PPU attic, so it is more important to pay attention to other important factors.
Technology advantages:
- Spraying eliminates the formation of seams. Polyurethane foam fills all cracks, hard-to-reach places. In one piece thermal insulation there are no areas where cold bridges could form.
- Polyurethane foam can be applied to surfaces of any complexity. This is especially important when the attic has a broken roof type.
- High thermal insulation properties of polyurethane foam allow high-quality insulation with a thin layer. Thermal insulation does not steal usable space, leaving more free space inside the attic.
- Thermal insulation by spraying occurs many times faster than the laying of piece material.
- The polyurethane foam adheres firmly to the surface. Moisture and fungus do not form under the insulation. It does not slide down an inclined plane.
Despite the high cost of the technology, PU foam insulation in some cases allows you to save money. There are mansards, the roofs of which were erected with violations. Most often, there is no waterproofing. When using basalt insulation, the membrane will have to be laid. In addition, from the inside of the attic, cotton slabs must be similarly covered with a vapor barrier. High-quality membranes are expensive, plus an additional payment for their installation. Polyurethane foam does not need membrane protection. So the question of the favorable price of each technology remains controversial.
Polyurethane foam fills all voids, reliably adheres to surfaces of any complexity
The disadvantage of this technology is the fear of PPU sun rays. Polyurethane foam is destroyed by ultraviolet radiation. However, insulation with any material ends with a finish, therefore, under the clapboard or drywall, polyurethane foam will last for many years. Firm adhesion to the surface is considered a plus and at the same time a minus. If a roof element requires repair, the section of thermal insulation is stripped off and cannot be reused.
Important! In terms of fire resistance, PPU belongs to the G-2 flammability class.
PU foam does not support combustion, but when exposed to an open source of fire, the foam melts and smokes. The last drawback is the inability to carry out insulation on your own. Spraying is done with special equipment with the involvement of a hired team.
How to prepare an attic from the inside for foam insulation
The process of warming begins with preparatory measures. All foreign objects are removed from the attic. First, they will get in the way. Secondly, adhering foam is difficult to remove. Expensive tools, furniture and other valuable items can be damaged.
Peeling paint and other old finishes are removed before insulating the attic elements.
After clearing the space, they begin to prepare the surface, where the spraying of polyurethane foam is provided. The peeling paint is cleaned off with a spatula. If there is an old insulation, decrepit cladding, everything is dismantled, getting rid of dust. The wooden roof elements are inspected for integrity. Damaged beams are replaced or repaired.
The attic has windows. They are all covered with a film along with window sills and slopes. It is difficult to remove foam that has got on an unprotected area without a trace, so you will have to try with a reliable cover.
How to insulate an attic with polyurethane foam
Polyurethane foam spraying technology is complex and requires the use of special equipment. To insulate the attic in this way, you will have to hire a team of specialists. The purchase of equipment is not profitable for performing the work once. It is another matter if in the future there is a desire to provide paid services for the insulation of building objects.
For spraying polyurethane foam, special equipment is required
In general terms, PU foam insulation provides for the following actions:
- the surface intended for insulation is cleaned of peeling paint, old cladding, thermal insulation and other contaminants;
- in the absence of a lag, they are equipped from a bar;
- the installation for spraying is assembled directly at the work site;
- spray the first layer, give time to harden;
- if necessary, spray a second layer, again give time to harden;
- lathing is attached to the lags or the installation of the finishing plating is carried out directly on them.
Laying under the sheathing of a vapor barrier or waterproofing membrane is not done.
Spraying is performed in a protective overalls, gloves and a mask that completely covers the face
Methods for installing polyurethane foam insulation
Let's make a reservation right away, the insulation of the attic outside (during the construction phase) has many difficulties associated primarily with the necessary conditions for high-quality application of a layer of material (temperature, humidity, lack of precipitation, and much more). Therefore, according to the recommendations of the manufacturers of this material, insulation of the attic from the inside is widely practiced. The technology presupposes two main methods of applying polyurethane foam coatings:
- It is advisable to insulate the attic under construction by direct spraying of the material onto the surfaces to be treated. This will ensure the integrity of the coating of all structural elements of the rafter system. Usually, several layers of insulation are applied, with a total thickness of 6-10 cm (this indicator is determined by heat engineering calculations based on climatic conditions in the construction region).
- If there is a need to insulate an exploited house with an attic floor, then it is advisable to use another technology that allows you to preserve the existing finishing coatings. Its meaning lies in pumping thermal insulation over the surface of the decorative finish (drywall, lining, wood panels, etc.). For this, technological openings of a small section are cut in the finishing materials (working openings through which foam is supplied, and control ones, which allow monitoring the level and quality of filling the voids behind the decorative cladding). The same technology is used to insulate and provide sound insulation for frame partitions.
Remember that only professionals can be trusted to carry out work on the installation of thermal insulation of attic rooms, any mistake will lead to irreparable consequences.
Our company performs insulation of houses with an attic using polyurethane foam at the most affordable price in Moscow and the Moscow region. Take advantage of a unique offer, get a free consultation of our manager on all issues of polyurethane foam insulation right now.
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Professional advice
PU foam insulation is considered a complex technology. It is better to trust the work to hired specialists. If you decide to comprehend this "art" on your own, you should heed the advice of professionals:
- When mixing polyurethane foam with water, a ratio of 1: 1 is adhered to.
- If the working mixture has darkened, the proportions are not correct. The properties of the insulation will deteriorate.
- When insulating in the middle lane of the attic, the thickness of the polyurethane foam is applied at least 15 cm.
- It is optimal to carry out insulation in warm weather, when the air temperature is above + 10 ° C.
- During spraying, moderate humidity is created in the attic. Excess moisture is not allowed. The insulation is capable of peeling off the surface or hardening with large air bubbles.
- During the operation of the spraying equipment, ventilation is provided in the attic.
- Spray foam from a pistol, moving from the bottom up. The nozzle is removed from the insulated surface at a distance of 50 cm.
- In one pass, a layer of the required thickness is immediately sprayed. It is impossible to return with a pistol to non-frozen areas of the foam.
At the end of the work, the equipment is flushed. If the polyurethane foam accidentally adheres to the body, carefully remove it with a solvent.
Comparison of PU foam with other heaters
Thermal insulation with polyurethane foam in one layer with a thickness of 2.5 cm is comparable in characteristics to brickwork 86 cm thick, wooden bar - 14 cm, foam block - 36 cm, cork board - 5 cm, polystyrene - 4 cm.
| Material | Service life, years | Max. thermal conductivity coefficient, W / m * k | Density, kg / m3 | Porosity | Operating temperature range |
| Polyurethane foam | 25-50 | 0,028 | 8-100 | Closed | -180, +150 |
| Minvata | 5 | 0,058 | 55-150 | Open | -40, +700 |
| Penoizol | 10 | 0,047 | 8-15 | Open | -50, +120 |
| Cork insulation | 8 | 0,060 | 220-240 | Closed | -30, +90 |
| Expanded polystyrene | 7-12 | 0,060 | 40-150 | Closed | -100, +80 |
| Foam concrete | 10 | 0,160 | 250-400 | Open | -30, +120 |
