Condensate in the attic: causes of occurrence and how to eliminate?
The attic serves people very well and successfully, but only in one case - when it is decorated and prepared properly. It is important to deal not only with penetrating winds and precipitation, but also with condensing moisture. Provide similar troubles worth it in advance. If the problem arose during the operation, it has to be solved quickly.
Causes of
Condensate in the attic appears due to:
- poor quality insulation;
- thermal weakness;
- builders ignoring the ventilation of the space under the roof;
- unprofessional vapor barrier or protection from getting wet;
- poor installation of slopes and skylights.
The general conclusion: liquid condensation begins as a result of deviations from the standard technology. Also, this problem may occur when repairs are made using poor quality materials.
When an impenetrable film is placed under the roof, excellent conditions are created for the formation of condensate.
Immediate savings will result in significant costs and it is important to know how to fix the problem.
Ventilation
When condensation forms in the attic, it is necessary to work on air exchange.
It needs to be provided constantly and in all internal volume.
Having solved this problem, the builders will achieve instant drying of the condensing liquid, it simply will not have time to form drops. But to fundamentally get rid of the problem, such a measure does not help simply because it is a struggle with the consequences, and not with a cause.
It is recommended to invite experts and conduct thermal imaging inspection of roofing structures.Almost certainly you will need to reschedule dormer windows, add insulation or create additional ventilation ducts.
Important: when the attic is sweating, you can safely take care of the ventilation, without fear that it will lead to overcooling of living rooms. When everything is done correctly, there is no risk to freeze the house.
Cold attic
When the cold attic gets wet, it is exposed to accumulation of condensate, you need to adjust to start its ventilation. Do not overlap rafters and crates. If this cannot be done without, it will be necessary to form a sewing with gaps through which air can circulate freely.
Laying slate and ondulin without films laid under them allows for automatic ventilation, then air flow between the parts of the roof can move smoothly. But when using metal tile the risk of condensation still remains.
Ventilation on the dual-slope roof is placed in the gables, for example, taking care of the loose placement of the overhangs of the overhangs. Arranging a narrow gap at the same distance from each other, you can improve the efficiency of ventilation.When the gables are stone, or the resource from the opening of the hole is already used, additional airing must be done.
They are placed either on opposite walls, or simply use conventional-type ventilation grilles, which are complemented with mosquito nets.
With a hip roof, this approach is not suitable. The entrance is prepared at the bottom of the binder, and the air comes out at the ridge. When the overhangs are hemmed with wood, it is permissible to set the timber loosely, leaving a gap of 2-4 mm. Special holes are made in the plastic layer, then the panel is called soffit.
Warm attic
Heating systems of the modern level almost exclude natural circulation, therefore you simply cannot do without enhanced ventilation. Under the shingles and sheet metal hem counter-rail, providing local ventilation of the site. A windproof film should be used under a metal roof. When slate is located at the top, there is almost no need for counter-racks, since the pie itself does not interfere with circulation.
Air intake is organized through the windows, and its exit through special openings. If they are not, the hood is equipped with aerators in the form of "fungi".
Tips for the right device
In a private house has its own intricacies of the arrangement of the roof, preventing the appearance of condensation:
- you need as much as possible to bring together the holes in the ridges of the roofs among themselves;
- relies on the durability of ventilation structures, their ability to resist strong weather effects;
- should be made between the rafters;
- thinking through the device holes, you need to make them so as to avoid air pollution or blocking its flow;
- air handling units are mounted in the cleanest point of the attic.
Solutions
If the insulation in the attic is wet, it is necessary to change the design so that the dew point is located inside the insulation layer. The mineral wool layer must be at least 250 mm. If water is collected under a vapor barrier, it is necessary to place a membrane permeable to steam above the insulation.
Roof insulation
The appearance of liquid in the attic may be due just to the fact that the protective layer is too thin. Finding a weak spot is easy, even without the help of a thermal imager. When the snow falls, it is necessary to inspect its layer, where melting will be noticed, there is excessive heat.
Elimination of ventilation deficiencies
So that even moisture that gets there in the attic of a wooden house does not linger, it is recommended to place the ventilation holes correctly - under the eaves of the roofs and in their skates. When the air circulation inside is correct and clear, the accumulation of snow and ice on the surface of the roof is minimized.
Moreover, a well-organized movement of air masses helps to reduce snow sticking to the roof surface.
When using aerators (at the final stage of work), you can give them any form you want.
Replacement of low-quality heat and waterproofing
When the appearance of condensate becomes a consequence of the use of low-quality materials, you first need to change the film of the usual sample on the membrane layer. This coating reliably allows water to flow out, but does not allow it to wade inside.
The surface, which is covered with nap, avoids the formation of droplets.
It so happens that these steps do not help. Then you need to change the crate and vapor barrier material. When the outflow of air is broken and its circulation does not occur, dampness accumulates more actively.It will be necessary to equip this part of the room, attracting a trained specialist and creating the required 4 cm of ventilation gap.
Dormer windows and other devices
Providing dormer windows is not the most efficient way to drain a loft. The minimum allowable size is 600x800 mm. Windows set on mutually opposing gables. The distance to the eaves, sides of the building and the ridge is strictly the same.
A modern solution to this problem is an aerator.output to the highest point of the roof (roof slope). It is customary to distinguish between point and monolithic aeration means. The first must be supplemented with fans, and the second are made as a plate placed along the ridge.
Roof repair
When repairing a roof, mineral materials for overlapping should be laid down with a layer of at least 20 cm (as recommended by GOST). Some manufacturers indicate that it is necessary to make insulation at least 30-35 cm. By observing these rules and checking problem areas with thermal imagers, you can guarantee complete success.
Tips and tricks
It is important not to forget about the creation of perforated soffits near the eaves.
The insulation layer is always placed strictly along the rafters to avoid the appearance of liquid droplets.
Considering that the cost of creating a good attic is up to 1/5 of all expenses for building a house, it is more practical and more economical to do everything at once than to return to work again after a while.
When creating air vents, it is worth forming at least 1 square meter. m passes for air to 500 square meters. m square. This is sufficient to maintain freshness without excessive heat loss.
How to eliminate condensate in the attic, see the following video.
