No Attic Ventilation

However many building code officials have accepted unvented attics on a case by case basis when presented with compelling evidence such as hygrothermal modeling of.

No attic ventilation.

If the attic ventilation system is not a balanced combination of intake vents installed in the soffit under eave or at the roof s bottom edge and exhaust vents installed at or near the roof s peak the attic ventilation system will not be efficient and effective. For instance attic ventilation is used widely in cold climates to evacuate the warm moist air that escapes from the living space below. This creates a natural air flow by drawing in the air from outside pushing it up and out through the vent at the top of the house. For proper ventilation it isn t enough for air to simply get into your attic.

Attic venting fans attic fans serve a different function removing the hot and moist air from the attic and leaving the space below the attic floor alone. The majority of roofing experts agree that ridge vents are the most effective and cost effective roof vents available. Since 2004 international code council icc supplements to the international residential code irc mean unvented attic assemblies have been accepted by the building codes in residential but not commercial applications. Your roof vents may not look anything like the ones shown in this article.

For this reason the square footage of vent space at the base of the roof and at the peak. If you don t see any attic vents on the roof or in the eaves you need to add some. One reason for the lack of agreement over attic ventilation is the tremendous variation in climate across north america. The most common way to add ventilation to an attic is by installing air intakes in the soffits and putting an outlet at the gable of the house.

This is called passive ventilation. Your roof may have a ridge vent which is a low profile continuous roof air vent running along the peak of the roof. This can lead to a number of serious and expensive problems. Gable vents may circulate air through only a small percentage of your attic.

Without baffles blinders that prevent outside air from crossing over the vent a ridge vent may create almost no ventilation at all. It must also circulate. Attic ventilation works on the principle that heated air naturally rises primarily utilizing two types of vents. Intake vents located at the lowest part of the roof under the eaves allow cool.

These fans circulate the air within the. Rarely will you find a building practice that works everywhere. Look at your eaves and roof.