Vapor permeability of concrete: features of properties of

Often in construction articles there is an expression - vapor permeability of concrete walls. It means the ability of the material to pass water vapor, in a popular way - to “breathe”. This parameter is of great importance, as waste products are constantly being formed in the living room, which must be constantly brought outside.

General information

If you do not create normal ventilation in the room, it will create dampness, which will lead to the appearance of fungus and mold. Their excretion can harm our health.

On the other hand, vapor permeability affects the ability of a material to accumulate moisture.

Permeability is denoted by a Latin letter? and measured in mg / (m * h * Pa). The value indicates the amount of water vapor that can pass through the wall material over an area of ​​1 m.² and with its thickness of 1 m for 1 hour, as well as the difference between the external and internal pressure of 1 Pa.

High water vapor carrying capacity for:

• foam concrete;
• aerated concrete;
• pearl concrete;
• керамзитобетона.

Closes the table - heavy concrete.

Tip: if you need to make a technological channel in the foundation, diamond drilling of holes in concrete will help you.

Gas concrete

1. Using the material as a walling structure makes it possible to avoid the accumulation of unwanted moisture inside the walls and to preserve its heat-saving properties, which will prevent possible destruction.
2. Any aerated concrete and foam concrete block is in its composition? 60% of air, thanks to which the vapor permeability of aerated concrete is recognized at a good level, the walls in this case can "breathe".
3. Water vapor percolates through the material, but does not condense in it.

Паропроницаемость aerated concrete, так же, как и foam concrete, значительно превосходит тяжелый бетон – у первого 0,18-0,23, у второго - (0,11-0,26), у третьего – 0,03 мг/м*ч*Па.

I would like to especially emphasize that the structure of the material ensures that it effectively removes moisture into the environment, so that even when the material freezes, it does not collapse - it is forced out through the open pores. Therefore, preparing the finishing of aerated concrete walls, you should take into account this feature and select the appropriate plaster, putty and paint.

The instruction strictly regulates that their vapor permeability parameters are not lower than the aerated concrete blocks used for construction.

Tip: do not forget that the parameters of vapor permeability depend on the density of aerated concrete and may differ by half.

К примеру, если вы используете бетонные блоки с плотностью D400 – у них коэффициент равен 0,23 мг/м ч Па, а у D500 он уже ниже - 0,20 мг/м ч Па. В первом случае цифры говорят о том, что стены будут иметь более высокую «дышащую» способность. Так что при подборе отделочных материалов для стен из aerated concrete D400, следите, чтобы у них коэффициент паропроницаемости был такой же или выше.

Otherwise, this will lead to deterioration of moisture removal from the walls, which will affect the decrease in the level of comfort of living in the house. It should also be noted that if you applied vapor-permeable paint for aerated concrete to the exterior, and non-permeable materials for the inside, the steam will simply accumulate inside the room, making it moist.

Керамзитобетон

The vapor permeability of expanded clay blocks depends on the amount of filler in its composition, namely, expanded clay - foamed baked clay. In Europe, such products are called eco-or bioblocks.

Tip: if you can not cut the clay block with a conventional circle and grinder, use a diamond. For example, cutting reinforced concrete with diamond circles makes it possible to quickly solve the problem.

Polystyrene concrete

The material is another representative of cellular concrete. The vapor permeability of polystyrene concrete is usually equated to wood. You can make it yourself.

Today, more attention is beginning to be paid not only to the thermal properties of wall structures, but also to the comfort of living in a building. By thermal inertness and vapor permeability, polystyrene concrete resembles wooden materials, and heat transfer resistance can be achieved by changing its thickness. Therefore, bulk monolithic polystyrene concrete is usually used, which is cheaper than finished slabs.

Conclusion

Из статьи вы узнали, что есть такой параметр у стройматериалов, как паропроницаемость. Он дает возможность выводить влагу за пределы стен строения, улучшая их прочность и характеристики. Паропроницаемость foam concrete и aerated concrete, а также тяжелого бетона отличается своими показателями, что необходимо учитывать при выборе отделочных материалов. Видео в этой статье поможет найти вам дополнительную информацию по этой тематике.