Attic Ventilation

Today it is common to see older houses being weatherized to keep cold air out and costly warm air in. New homes are built to meet higher energy standards than ever before. A common side effect of airtight homes is poor ventilation that can lead to accumulated moisture and poor indoor air quality.

Attic ventilation is intended to remove moisture from the attic during the heating season and to remove solar heat from the attic during the cooling season. Adding attic ventilation during weatherization, however, is seldom necessary.

Adding attic ventilation to cure a moisture problem will not work if excess moisture migrates up from the living space. Preventing moisture from entering the attic in the first place is now recognized as the best way to keep attic insulation dry. Ceilings should be thoroughly air-sealed to prevent leakage of moist indoor air through the ceiling, which deposits condensation in the insulation during cold weather. Adding ventilation only is not the answer to stopping ice dams. Bypasses must also be sealed, and insulation brought to adequate levels.

If kitchen and bath exhaust fans are not vented through the roof, they are venting warm, moist air into the attic, adding to the problems of mold and frost. Houle Insulation also adds insulated ductwork to the exhaust fans and vents them through the roof to a dampered roof vent.

Attic venting can increase ceiling air leakage by increasing the stack effect.

If necessary, as standard measures of re-insulating your homes attic, Houle Insulation will add six-foot long air chutes for soffit ventilation and roof vents to the roof peak.