It is important to correctly conduct the insulation of the floor, as this will prevent heat loss from the building and ensure the most comfortable temperature. There are two ways of insulation: top and bottom. Each case must be considered separately, since with thermal protection of different elements of the building, only one of them will be competent from the point of view of heat engineering. When is it better to apply floor insulation in a wooden house or in a summer cottage from below?
Basic constructions for insulation
Thermal protection of vertical elements in a private house is required in three cases:
- floor insulation over a cold basement;
- floor floors;
- attic floor in the presence of a cold attic.
In the second case, work is carried out to increase the noise insulation characteristics.
Warming in a wooden house helps prevent the following problems:
- overspending in the heating system;
- violation of the temperature and humidity of the room;
- decay of floor structures;
- the appearance of mold and fungus.
In a private house or in the country, it is worth thinking about conducting thermal insulation measures at the design stage.
In what cases and why is insulation from below correct
Insulation of the floor above the cold attic is best done from above, but the thermal protection of the ceiling above the basement is technically more competent to perform from below. This has its reasons:
- there is no decrease in the height of the premises on the ground floor;
- there is no need to choose a dense rigid insulation that can withstand loads from residents, furniture and equipment;
- protection against freezing not only the floor, but also the entire wooden floor;
- displacement of the dew point (the line on which the condensate falls) to the surface of the floor from the thickness of the structure, which prevents decay.
But when carrying out work in a private house or in the country, some difficulties may arise, associated precisely with work from below:
- the need for more reliable fixing of the insulation;
- complexity of work in low underground conditions;
- the need for work on the ceiling leads to rapid fatigue of workers;
- restriction on the type of insulation.
Therefore, if you are looking for simpler methods of insulation, we recommend that you read the following articles:
- Foam floor insulation
- Floor insulation “Penopleks”
- Insulation of the frame house floor
- Mineral wool insulation
Material requirements
Features of the method of work are forced to use only certain thermal insulation materials. The main requirements when conducting heat-shielding measures in a private wooden house or in a summer cottage from the bottom include:
- a small mass of insulation, since the place of attachment to the ceiling experiences increased loads;
- the convenience of use;
- high efficiency;
- structural cohesion (bulk materials are not suitable);
- fire resistance is possible, since when carrying out work in a wooden house it is necessary to ensure maximum fire safety.
There are many options for materials that satisfy all these requirements.
Materials for insulation from below
As thermal insulation layers it is recommended to use:
- mineral wool, produced in the form of rolls;
- Styrofoam;
- polyurethane foam.
Mineral wool in the form of rigid plates can also be used, it is installed between the beams of the wooden floor in the country or in an individual building from below so that the width of the plate is slightly larger than the distance between the beams in cleanliness. In this case, the hard insulation will be held by friction. They also come in the installation of thermal protection on the attic roof.
Mineral wool insulation has the following advantages:
- high efficiency;
- incombustibility;
- low degree of water absorption;
- resistance to biological influences.
The main drawback of the material is that workers need reliable protection against the ingress of fibers on the skin and lungs: gloves, work clothes, masks.
In the country and in the house, you can also use inexpensive polystyrene. Its main advantage, of course, is cost, but there are others:
- good thermal insulation;
- low degree of water absorption;
- ease of installation;
- no need for sophisticated tools or workwear.
The fact that the material has low strength is not important when insulating from below, but combustibility and instability to the simultaneous influence of negative temperatures and a humid environment are obvious disadvantages. The solution to the second issue may be reliable waterproofing and protection against steam. Due to the low cost, this type of material is quite widespread.
The third option of insulation was polyurethane foam. This type of thermal protection has the following positive characteristics:
- ease of installation;
- reliability of fixing due to penetration into cracks, bumps and inaccessible places;
- efficiency as thermal protection;
- resistance to biological influences.
More information about this type of insulation as thermal protection of structures, including ceilings, can be found in the article "Foam house insulation".
Mounting technology
The fixing methods for each material are different, but when installing reliable thermal protection, it is necessary to observe the order of the layers, which is the same for all. When insulating from the side of a cold basement or underground, materials for insulation and protection of the insulation are arranged in the following order:
- waterproofing;
- thermal insulation layer;
- vapor barrier;
- floor structure;
- floor construction.
Compliance with this very order will ensure a normal temperature and humidity regime in the house. Next, you need to consider in more detail the location of the protective materials.
In a house with an existing wooden floor of the 1st floor, insulation from below can be done by attaching bars with a section from 50x50 to 50x100 to the bottom beams and placing insulation material between them. After waterproofing, the resulting pie can be hemmed with boards.
Waterproofing
Cold air from the basement may fall in the form of condensation on the warm surface of the ceiling. The constant presence of moisture on the structure will lead to the formation of mold or fungus, and subsequently to decay, even if the wood is treated with special compounds. In addition, condensate is very harmful to the thermal insulation layer. It can lead to increased thermal conductivity. To avoid this, a layer of waterproofing is laid on the side of cold air.
Vapor barrier
From the side of a warm room, the situation is changing. The problem here is not liquid water, but warm steam. Penetrating into the thickness of the material, as it approaches the outer surface, the vapor cools and turns into water. This process is especially dangerous in that, unlike the previous case, moisture is formed not on the surface, but in the thickness of the structure. This increases the risk of wetting and destruction of the insulation and decay of wood elements.
The vapor barrier layer prevents the penetration of steam from the room.
When warming the overlap of the upper floor, the layout of the layers changes. On the basis of physics, it is necessary to place protection against steam from the side of warm air, and from moisture from the side of cold.
As both types of protection in the simplest case, you can use a plastic film. When warming the basement, moisture and wind-proof membranes are sometimes used as waterproofing. They do not prevent air movement, but reliably retain moisture.
To reliably protect the house from the penetration of the cold, you need to think about it at the design stage, but measures to protect the basement from below allow you to carry out work during operation.
This installation method does not require disassembly of the flooring and does not create uncomfortable conditions for residents.
Video about floor insulation from the basement with polyurethane foam:
It is important to carefully choose the material for insulation and follow all the manufacturer's recommendations. This will ensure reliable and long work. The layer thickness is selected depending on the climatic region and the selected insulation. Knowing the thermal conductivity and layer thickness, competent calculations can be performed even by a non-professional. This is possible thanks to the convenient program "Teremok", presented in the public domain.