Insulating the floor along joists with polystyrene foam in a wooden house: how to insulate

Floor insulation with expanded polystyrene is often done on the living room side or on the basement side. The latter option is suitable for houses on a conventional monolithic foundation with underground observations. If you have a spacious basement and a pile foundation, you should choose the second option. A detailed description of each technology and useful tips from experienced craftsmen can be found in the presented article.

Recommendations for choosing insulation

Before you start work, you need to select the material and take into account several features. It should be understood that polystyrene foam is not suitable for floor insulation because it is not strong enough. Therefore, you can only choose polystyrene foam, which is resistant to impacts and loads, as well as other advantages:

• does not absorb income;
• protects well from the cold;
• does not rot or mold;
• not attractive to rodents;
• very light;
• easy to install.

You should not choose polystyrene foam for floor insulation in a wooden house; you should go straight to choosing polystyrene foam. conditionally use the PSB-S-35 brand. This type of slab is characterized by good thermal insulation (thermal conductivity coefficient 0.4 W/m2) and low moisture absorption (no more than 2%). If the load is large, rationally market-oriented PSB-S-50 (well suited for garages and utility rooms).

When planning floor insulation using polystyrene foam, you must also pay attention to several features:

• It is advisable to first level the rough surface, because in this case the thermal insulation will be uneven due to the uneven distribution of the material;
• be sure to use waterproofing to prevent burning of wooden logs;
• Wood always releases a share of water vapor, so it is necessary to leave a small gap between the joists and the possibility - then insulating the floor with polystyrene foam in a wooden house will work correctly.

Base insulation technology

Now you need to figure out how to insulate the floor with polystyrene foam in a wooden house. At home, prepare the necessary tools and supplies:

• the insulation itself;
• knife;
• level;
• roulette;
• vapor barrier;
• stapler for construction work;
• pencil.

The insulation of the floor with foam plastic between the joists can be carried out according to different schemes, for example, superficially. This technology is suitable for houses that have a cellar or basement. Failures also apply to buildings that have a pile or pile-screw foundation. In this case, the insulation is placed in the space between the frame and the finished floor. This work is carried out from the basement. The sequence of actions is as follows:

1. Removing old flooring.
2. Inspection of joists, replacement of rotten parts - completely or partially. Installing a new beam in their place, adjusting it to size and fixing it using galvanized corners or channels.
3. To properly coordinate the insulation of a wooden house with polystyrene foam, you need to lay a vapor barrier. The sheets are overlapped by at least 10 cm and secured with tape.
4. Install cranial bars with a cross section of 30*30 mm. They are attached to the sides of the joists to create support for the insulation.
5. Then lay the material between the joists. It is first cut into fragments necessary for collection and collection. The insulation is fixed using polyurethane foam; wooden slats can be installed for the same purposes. This kind of insulation of floors with foam plastic makes it so that it is lower than the joist.
6. The waterproofing is also laid overlapping and secured with tape.
7. The last stage is finishing, for example, from boards or moisture-resistant plywood.

Top insulation technology

There are several internal ways to insulate a floor with polystyrene foam, one of them is laying the material on top. This is a simpler method, because the installation concerns an important aspect of the living space - there is no need to go into the basement. This technology is suitable for standard houses on a monolithic foundation or with a low subfloor.

However, despite all the advantages, insulating a wooden floor with polystyrene foam on top also has disadvantages. The main disadvantage is due to the fact that part of the space has to be wasted, and therefore the overall savings are high. It is also necessary to re-hang the doors, otherwise they will not be able to be opened. But in general, there is no need to doubt whether it is possible to insulate the floor with polystyrene foam on top. This is a proven technology that consists of the following manufacturers:

1. They dismantle the cleaning floor, inspect the laggy parts and, if necessary, replace the rotten parts, as in the case of discovery.
2. The cranial beam is installed - the basis for the future subfloor.
3. Wooden boards or panels with a thickness of 30 mm or more are mounted on it.
4. Insulating floors in a wooden house with polystyrene foam also involves treating all boards and beams with an antiseptic composition.
5. A waterproofing film is overlapped by at least 10 cm on the installed rough base and secured with tape.
6. The insulation material itself goes on top of it, then the vapor barrier.
7. Next, you need to install a counter-lattice to leave a gap for ventilation. This is a mandatory step, regardless of the choice of how to insulate the floor in a wooden house with polystyrene foam.

Thus, foam plastic between floor joists is not the best insulation. Highly reliable polystyrene foam with high chemical strength and resistance to moisture, temperature changes and rotting. You can mount it yourself by choosing the thickness of the surface of the upper or lower surface.