Loft and attic it borders with the roof almost all sides, and comfort is strongly dependent on the ambient temperature. Without reliable insulation in the attic, it is impossible to ensure a comfortable stay.
Why do I need insulation
If we neglect the thermal insulation and limited only to heating of the attic, the following situation may occur:
- In winter, warm air will quickly go out of the room, which would entail considerable financial costs.
- Upon contact of hot air with the roof, the snow on it will melt and form ice cover and icicles that may cause damage to the roofing.
- On the inner surface of the roof in the cold condensate will be formed, leading to rotting elements truss system.
- During the summer, the room will be intensively heated to such an extent that living in it may become impossible.
Warming of the attic from inside - a task more difficult than conventional insulation of rooms:
- The need for insulation coating does not only vertical surface but also to the roof, having a negative angle of inclination.
- The high probability of moisture from the roof on insulation and soaking.
- Opportunity to carry out work only in the warm season.
All these problems removes insulation attic space with polyurethane foam.
What is polyurethane foam
Polyurethane foam (abbreviated - PUF) was created in Germany in the late thirties of the last century for the needs of the aviation and defense industries. he was later used for the insulation of freezing and refrigerating compartments, and the seventies of the twentieth century it began to be used for thermal insulation of houses.
Polyurethane foam is a plastic permeated with millions of tiny air bubbles. Insulation consists of two components which are mixed in situ insulation of a special apparatus.
The components are supplied in separate containers attached to a special atomizing unit. When spraying the mixture and reacting it with carbon dioxide contained in the air, it is easy to foam, well adhering to any surface. After some time the foam hardens, and insulate the surface is coated with a continuous layer of durable material - polyurethane.
Thus is created and insulated layer protecting the premises from energy losses.
On peculiarities of polyurethane foam
Among all the properties of the polyurethane insulation is important for good the following characteristics:
- Low thermal conductivity - not more than 0.03 W / (m * K) due to the large number of closed air cells (85%);
- Low weight warming layer - 30-70 kg / cu m .;
- Complete watertightness for a material with closed pores;
- Fire safety level of D-2;
- High adhesion to all surfaces;
- Ability to create a thermal insulation layer of any thickness directly in the process;
- Good sound insulation;
- Rapid solidification time - about 1 chasa;
- Resistance to water, the material does not rot or deteriorate;
- It does not require treatment against insects and rodents, they can not live in this material;
- Long term use - up to 40-50 years.
The disadvantages of the polyurethane foam include:
- Susceptibility to UV radiation. Open the material under direct sunlight is rapidly destroyed;
- Carrying the insulation is carried out only with special equipment.
Polyurethane foam is applied to the surface in liquid form. After applying and reaction with carbon dioxide contained in the air, it foams and hardens rapidly.
By forming a plurality of air bubbles inside the material, its structure is very porous, which ensures high quality consumer.
Important! The use of polyurethane foam with closed-cell foam for insulation of the attic makes it possible to abandon the hydro- and vapor barrier.
insulation technology
surface preparation
In the attic is necessary to protect all of the items that might be hit and damage the spray polyurethane foam. Window glass, window sills and slopes covered with polyethylene film, which must be securely taped. Insulation falling on any surface, firmly adheres to it and clean the occasional drops and sprays will be very difficult. So, it is better to take the time to prevent such cases.
If the site of application of insulation had any coating (eg, old paint), it is better to remove. Otherwise, it may subsequently move away from the surface, and with it would go and insulation.
This is followed by an audit of the wooden elements of the lining, repair damaged parts, replace worn out. they will be inside the insulation, and get to them will not be possible after applying foam.
The material should be applied to a dry surface, so all the trash and dust is recommended to completely remove.
The necessary materials and tools
For the application of the insulation will need:
- Two containers for polyurethane components;
- mixing apparatus;
- Compressor;
- Connecting hoses;
- The spray gun;
- Respiratory mask or breathing protection;
- Gloves, overalls, shoes.
The coating process
An important feature of polyurethane foam insulation is that it can not be carried out without special equipment. Its acquisition for work in only one house is not profitable due to the high cost, so you need to either take it out, or seek the services of professionals.
The work is conducted in the following order:
- Work on the pre-treatment.
- If the insulation in place there is no system lag, you must install them. They can simultaneously perform the function of alignment and insulate surfaces.
- The attic space is going to plant for spraying.
- Is deposited a first layer of insulation thickness of 10-15 cm.
- If necessary, additional layers are applied only after complete drying of the previous ones.
- After drying of the last layer of wire mounting interior trim on the crate or directly on logs.
Mounting hydro- and vapor barrier, in contrast to other methods of thermal insulation, by using a polyurethane foam is not required.
When calculating the desired thickness of insulation is necessary to obtain a dew point outside the insulation layer.
Important nuances with insulation polyurethane foam
At work the following factors must be considered:
- The proportion of water and polyurethane foam when mixed should be 1: 1. Failure to do so leads to a sharp deterioration in the properties of the applied insulation.
- Quality control is carried out on the mixture of its color - darkening to a violation of the mixing ratio of components.
- For the middle band Russia warm loft foam layer need not less than 150 mm.
- air temperature during operation should be less than 10 aboutFROM.
- Application of insulation is allowed only if the average level of humidity. Exceeding this parameter can result in large bubbles in the bulk material or its detachment from the surface.
- When the need to ensure good ventilation of the attic.
When the spray gun must observe the basic rules:
- Sputtering material is carried out from bottom to top, at a distance of 50-60 cm from the insulated surface.
- The created layer must have a uniform thickness immediately to return after a few moments ago is not recommended - applying a new layer of old may precipitate.
- Polyurethane foam is non-toxic, and in contact with exposed skin can be removed with a cloth soaked in solvent.
After drying of the last layer it is recommended to protect the paint.
Advantages and disadvantages of technology
The use of spray polyurethane foam for thermal insulation of attics has the following advantages:
- The material is applied a seamless manner, which eliminates the occurrence of thermal bridges in the insulation.
- Spraying may be the surface of any shape and the most remote places. No complicated projections and recesses will not prevent the creation of proper insulation.
- Thin layer generated due to the high thermal insulation properties of the insulating material leaves more space for Life in the attic.
- Fast application of insulation as compared to sheet materials.
- Created layer is tightly bonded to the surface and is not subject to slipping and breakage.
- No need to use hydraulic and vapor barrier layers.
The disadvantages of the polyurethane foam include:
- Vulnerability to UV radiation. This drawback is easily eliminated by applying a protective layer of paint.
- Despite the good flame retardancy (flammability class G-2), the material starts to smolder when exposed to high temperatures. It must be protected from contact with objects that can be heated to high temperatures.
- The relatively high cost of the material.
The video of the polyurethane foam insulation
There is no ideal material for thermal insulation, which does not have drawbacks. However, polyurethane has so many advantages that it can be recommended for the insulation of attics in private homes.
