Aerated concrete is a fairly warm material. Its thermal performance is about three times better than that of hollow ceramic bricks. According to calculations, a cellular concrete wall is required three times thinner than a brick one, but in practice this design often needs additional thermal protection. Warming of a house from aerated concrete is best done outside.
Features of insulation
- The need for waterproofing. Aerated concrete absorbs moisture well, therefore, when warming, high-quality waterproofing materials are used. An unprotected wall is able to hold a large amount of water inside the cells, which freezing will lead to cracking and destruction of concrete;
- Using chemical anchors. Aerated concrete does not have high strength, so when using conventional wall plugs, cracks and chips can easily form on its surface, which can lead to the destruction of the wall;
- The need for conservation. Warming of an aerated concrete house is carried out several months after the completion of the masonry, so that the material dries out. If the facade insulation is planned to be carried out immediately, then additional measures are required to protect the material from moisture during construction.
Options for additional thermal protection
When installing the insulation from the outside, the service life of the building is extended, the internal space is not affected, and moist air is easily removed from the wall to the street. But with a high building height, the use of the services of industrial climbers is required, which greatly increases the cost of insulation work.
Insulation from the inside can be performed at any height of the building, but it is worth remembering that in this case the wall needs vapor barrier and water protection. The insulation will last less than in the previous case, and the usable space of the premises will be reduced. This option is undesirable for low-rise construction, as specialists consider it ineffective.
Materials for thermal insulation of the facade
When designing a house by professionals, a careful calculation of the required thickness of the insulation is carried out. With an independent erection, you can take the size approximately, since the aerated concrete house is warm in itself. Most often, mineral wool and foam are used for thermal insulation. Thermal insulation characteristics are approximately the same.
It is important to choose high-quality materials, since the service life of the facade structure, the frequency of replacement and the installation cost depend on this.
Foam insulation
Polyfoam costs half as much as mineral wool. The main disadvantage of this material is that it does not let steam through, the walls of the house do not “breathe”, so the rooms require additional ventilation. In the absence of sufficient air movement in the building, condensation forms, the presence of which leads to the appearance of mold and fungus.
Work with foam should be performed in the following order:
- Cleaning the wall from pollution;
- removal of all irregularities and protrusions on the wall, if any;
- treatment with antiseptic compounds to prevent the appearance of fungus and mold;
- gluing fiberglass mesh near windows to increase strength;
- applying special glue to the insulation and wall;
- gluing foam sheets outside the wall;
- plastering and painting the surface after the glue dries.
Additionally, the insulation layer can be fixed to the wall with plastic dowels.
To perform the work, you will need polystyrene, special glue and a notched trowel for its application, plastic dowels and a fiberglass mesh.
The service life of the foam when fixed outside in a climate with significant temperature drops is 20 years, in milder conditions the material can last up to 50 years.
When insulating with polystyrene foam, a question may arise regarding the fire safety of the finish, but using special flame retardants, the material can be made non-combustible.
The material does not emit harmful substances during operation and is subject to secondary processing, which allows us to talk about its environmental safety.
A more expensive alternative to polystyrene is extruded polystyrene foam. It has greater strength, but in most cases its use is unreasonable, since for facade work, inexpensive and lightweight materials are preferable. But a significant advantage - the lack of the need for waterproofing, allows him to remain in the ranks of the facade insulation.
Mineral wool insulation
Mineral wool thermal insulation became the main competitor of polystyrene foam. The material is used in slabs, since rolled cotton can eventually sag and cease to fulfill its functions.
Installation of thermal insulation from the outside is carried out in the following order:
- Cleaning the insulated surface from dirt and dust;
- alignment if necessary;
- applying an antiseptic;
- applying a special adhesive composition;
- fixing plates in the design position;
- fastening with plastic dowels;
- installation on top of insulation of fiberglass mesh for a firm fit of the plaster;
- applying an additional layer of glue;
- after the glue dries, the plaster and the wall are painted.
Unlike polystyrene, mineral insulation has good vapor permeability, does not require additional ventilation. Some types of material can withstand temperatures up to 1000 degrees Celsius without igniting and not starting to melt. Minvata is able to last up to 70 years.
Mineral wool weighs more than polystyrene, so it has a greater effect on the foundations of the building. This should be taken into account with a small bearing capacity of structures.
Work with mineral wool is always carried out in overalls, gloves, a protective mask. Particles of material that get on the skin cause irritation and itching. The mask does not allow them to enter the respiratory tract and harm the health of builders. This complicates the installation of the material.
Another obstacle to the use of this type of thermal insulation is its cost in excess of the price of foam.
Modern methods of insulation
One of the latest developments in the field of heat-insulating materials has become insulated plaster mixes. Warm plaster can increase the protective characteristics of the wall with its sufficient thickness.
A layer of material of 15 millimeters replaces 4 centimeters of foam. To improve the properties of the composition added sawdust or paper pulp. You can buy a ready-made mixture or cook it yourself.
The main advantages of the coating:
- Good soundproofing of the facade;
- resistance to the appearance of mold, fungus, insects, rodents;
- relatively low cost;
- environmental friendliness and naturalness;
- Fire safety;
- lack of additional protective equipment for workers.
Installation is carried out in the same way as with conventional mixes.
When applied externally, the coating requires additional protection against atmospheric moisture. To do this, a layer of ordinary plaster is applied over the insulated composition.
This material is best suited for internal work. Unlike previous types of insulation, plaster does not require vapor barrier and waterproofing.
The material is completely safe and can be used even in children's rooms and medical facilities.
We recommend you to watch the video, which tells about all the nuances: