How to place a vapor barrier - above or below a heater?
Hello! It was necessary to insulate the floor in a wooden house on wooden logs. Is it right if I made the following pie: flooring on the bars, then roofing material, vapor barrier, insulation, on top of which waterproofing, then left a ventilation gap and laid the floorboards? A friend says that steam will come from a warm room, not from a cold underground. Therefore, the vapor barrier film had to be placed on top of the insulation to prevent it from getting wet, and the waterproofing - down ... Which of us is right? Regards, Maxim.
Hello Maxim! Unfortunately, one had to heed the advice of a friend. The proposed arrangement of the floor above the cold underground is incorrect. With well-arranged ventilation of the cold underground, mineral wool insulation boards will not pick up moisture. Ventilation is also done so that the walls of the foundation and all wooden structures remain dry.
Important! For five years in a non-ventilated underground, wooden structures become unusable and require replacement.
Placement of vapor barrier
A vapor barrier layer is placed over the “warm” side of the insulation for the floor facing the room. In the figure, see position 5. The material will prevent the penetration of vapors of warm air saturated with water, so there will be no wetting of the insulation and moistening of wooden logs.
Insulation layer thickness
In accordance with the requirements of building codes governing the thermal protection of buildings, for the Moscow region, the thickness of the floor insulation located above the cold underground should be at least 200 mm.
If the height of the beams does not allow the installation of such a layer of thermal insulation, then use the transverse bars, which are installed on the logs. Thus, the required thickness of the insulation is achieved.
When doing the work on their own, it is possible that there will be errors that can bring a lot of trouble in the future. Therefore, it is better to trust the work of experienced craftsmen who are versed in the device technology of various floor coverings. If there are contentious issues, you should not start work until the truth is clarified.
