Norms of the
device One of the most important issues in construction thermal physics is the level of humidity in the structures. Its index significantly influences the coefficients of thermal conductivity and, as a result, on the level of heat transfer. Underestimation of the humidity and temperature regime leads to the release of condensate, the accumulation of moisture and, as a result, to the gradual destruction of the structure. The cause of improper ventilation may be several factors:
- Builders and designers underestimated the value of ventilation;
- Use of new constructive solutions and materials that are incompatible with old materials;
- Complicated regulatory requirements that can not always be met.
To make a normal thermal insulation between the rafters it is necessary to mount a 20 cm thick insulation. In this case, such a thickness can have a bad effect on the structure, because the rafters, in general, do not have sufficient stability. The solution is the use of suspended structures made of metal, on which it is possible to arrange insulation, which does not fit in the rafters.
It is known that the thermal insulation of the roof depends not only on the insulation layer, but also on the proper arrangement of ventilation. From the inside, water evaporation acts on the roof, which rise from the heated lower rooms. To solve this problem, it is necessary to properly perform the ventilation gap. The system works as follows: air freely circulates inside the structure and removes all accumulated moisture.
Note! Ventilation of the system also allows you to save on heating.
What is the benefit of roof ventilation?
Today, the domestic market is represented by a variety of materials with the properties of vapor permeability. The main ones are superdiffuse membranes and waterproofing films. Also there are ventilated films, however for their use it is necessary to have in the roofing system two gaps for ventilation. In such a system, the upper gap ventilates the waterproofing flooring, and the lower one - the rafter system.
The ventilation tasks are as follows:
- Removal of residual steam that penetrates from the lower rooms;
- Stabilizes the temperature at one level over the entire surface of the roof. This avoids the formation of ice at the eaves of the cornices as a result of melting snow;
- Reduces the temperature when the roof is heated strongly in the sun.
The device of a ventilated roof consists in that the air stream under a roof rose from a cornice upwards to the fad. Systems of this type are considered the best solution, because the air moves upwards in a natural way. Basic principles: cold air comes from below and comes from above, the maximum effect is achieved when air moves throughout the inner roof area.
Note! Traditional ventilation systems through the dormer windows are considered ineffective, and in the case of attics and not at all suitable.
Negative influence of lack of ventilation
Ventilated roofing is a necessary condition for the normal functioning and safety of the roof. If there is no ventilation, a large difference appears between the internal and external temperatures, and as a result, condensation forms. Without ventilation, it does not lead, so it gradually penetrates deep into the structure, rafters, insulation, which leads to a gradual destruction of them.
In addition, there are ideal conditions for the development of mold and fungus. But the most negative is that if the heater gets wet more than 5 percent, then its heat output will decrease by half. Important! It is common knowledge that fungus and mold have a negative impact on human health, so their education should be avoided.
In addition, as a result of the action of the condensate, the walls begin to deteriorate faster. In the summer, the sun heats the roof, which in combination with the action of ultraviolet significantly reduces the life of soft coatings. This, in turn, makes the location in the attic and attics at this time very uncomfortable.