- Why do you need thermal insulation of the attic
- The essence of insulation work
- The main criteria for choosing insulation
Much of the heat loss in private homes during the cold season occurs through the roof. In this regard, thermal insulation works are carried out in buildings with an unheated attic. In most cases, it is required to insulate the attic floor on load-bearing wooden beams. Let’s look at the technology of such thermal insulation.
Why do you need thermal insulation of the attic
The main function of an unexploited attic is to smooth out temperature differences between the interior of the house and the street. If the attic is not insulated, on average, during the heating season, up to a third of the heat in the house is lost through the roof, and, therefore, the cost of heating the building increases by the same amount..
How does heat loss occur? The fact is that in unheated attic floors, the air temperature is usually several degrees higher than outside. That is, in the winter in the attic it is frosty all the time, and in the summer, on the contrary, it is hot. The air from the heating systems rises to the ceiling. If the ceiling insulation is weak enough, then the heat partially goes to the attic, and does not heat the premises of the house.
There are other problems associated with poor attic insulation. For example, warm air in contact with a cold ceiling cools down and rushes back to the floor, thus causing increased reverse circulation and drafts. In hot weather, the opposite situation develops – hot air enters the rooms from the attic.
Such processes, in addition to thermal discomfort, are also fraught with the formation of ceiling condensation, which significantly increases the humidity in the house and leads to the appearance of mold. Condensation also forms inside the attic, causing rotting wooden structures and corrosion of metal elements. Heating the roof with air from the premises of the house through the attic in winter leads to the melting of the snow accumulated on the slopes of the roof with the formation of icicles and freezing of gutters and ebb tides.
The essence of insulation work
Thermal insulation of the attic floor is considered to be of high quality if it allows you to achieve certain results.
The main criteria for sufficient insulation of the attic are as follows:
- temperature jumps are minimal;
- the average temperature is close to the indicators of the rest of the premises of the house;
- the attic protects from the cold in winter and from the heat in summer, the costs of both heating and air conditioning are reduced;
- there is a small amount of condensation in a closed attic;
- in winter – a minimum of ice and icicles on the roof, the roofing materials are cold.
The principle of work on insulation is that in the plane of the floor beams between the heated rooms and the attic, a thermal insulating material is laid.
1 – crate; 2 – interior decoration; 3 – vapor barrier; 4 – floor beams; 5 – insulation; 6 – waterproofing
It’s important to know! It is also necessary to equip a vapor barrier and waterproofing, since the insulation must always be dry.
The process of insulating the attic is simple, but at the same time it is possible to achieve good thermal insulation, provided that the most important condition is observed – a sufficient thickness of the material used. On average, the minimum indicator fluctuates within 300 millimeters, regardless of the type of insulation. If the thickness is less, then heat leakage is inevitable..
The work procedure for insulation is simple – the material is placed at a height of about 200 millimeters between the beams. In this case, the run-up of the seams should be maximum. The rest of the insulation layer is located on top of the beams in a direction perpendicular to the lower layer of material. This technique allows you to reliably isolate the “cold bridges”.
The main criteria for choosing insulation
Currently, the master has at his disposal different types of heat insulators, suitable for laying on wooden beams. Since the degree of their effectiveness is comparable, in each case, when choosing a material, in addition to price parameters, weight and the degree of complexity of installation, one should be guided for the most part by the criteria of durability and safety of its use..
The resistance of the insulation to adverse factors is determined by:
- Strength, resistance to creases and compression, resistance to deformation or destruction under mechanical stress.
- Protection against destruction due to frost and overheating.
- Moisture resistance, air permeability – the material does not change its properties under the influence of water, but at the same time it allows air to pass through to ensure a normal balance of temperature and humidity in the house.
- Lack of organic constituents that can be susceptible to mold or appealing to rodents and insects.
The safety indicators for the operation of the material are as follows:
- Fire resistance. Insulation must be made of non-combustible material.
- Absence of volatile toxic substances in the composition of the material, including those formed as a result of exposure to flame.
- Chemical neutrality and hypoallergenicity of the insulation.
In conclusion, consider the advantages and disadvantages of different heaters. Depending on the type, thermal insulation material is supplied in the form of slabs, rolls, loose formations or briquettes.
Main insulation materials:
1. Mineral (glass, basalt) wool. Made from glass waste or gabbro-basalt rocks:
- pluses – durability, fire, chemical resistance;
- cons – contains allergens, so the installation must be carried out with protection of the organs of vision and respiration; particles of material may remain on clothing; glass wool is prone to creasing.
2. Ecowool (composition – waste paper and flame-extinguishing components):
- pluses – does not burn, does not rot, does not grow moldy, does not contain allergens;
- minus – requires enhanced vapor barrier.
3. Expanded clay, perlite, vermiculite (consist, respectively, of fired clay, volcanic rocks and mica):
- pluses – the material is protected from moisture, non-flammable, does not grow moldy, is unattractive to rodents, due to its flowability it is convenient when laying in hard-to-reach places;
- minus – heavy, creates a large load on structural elements.
4. Styrofoam (foamed plastic) and polystyrene (thermoplastic polymer):
- pluses – the lowest thermal conductivity among all heaters, does not collapse under the influence of moisture, does not grow moldy;
- cons – emits toxic substances when exposed to fire, damaged by rodents.
5. Polyurethane foam (gas-filled plastic), penoizol (carbamide foam):
- pluses – it is evenly applied to structural elements by spraying, as a result of which a continuous heat-resistant layer is created, the service life is calculated in decades;
- cons – roads, insulation work using this material can only be carried out by specialized firms.
6. Foil polyethylene foam (polyethylene foam with aluminum foil):
- pluses – it can also be used as a waterproofing agent;
- cons – does not allow air to pass through and can only be used as additional insulation, since its effectiveness is low.
7. Natural organic matter: peat slabs, reeds, sawdust:
- pluses – cheapness, light weight, good thermal protection;
- cons – flammability, susceptibility to damage by insects, fungi and mold.