Attic Mold Soffit Vents

Grab a flashlight and inspect your attic during the winter.

Attic mold soffit vents.

A home s ventilation system consists of everything from roof vents to the best attic fans without the right roofing and attic ventilation system your home can become uncomfortable and cost more to cool or heat. Moreover if you have asphalt shingles on the roof attic. The photograph at left shows severe mold on the underside of roof sheathing in a 1920 s cape cod attic where there was no under roof ventilation. Unlike growth in other areas of a home soffit growth does not appear to follow any reliable pattern.

As a certified licensed home inspector it is not correct to say too much ventilation is bad for an attic unless rain moisture is getting in. If you see dampness or frost you need better roof ventilation and some attic vents. Venting a homes attic is a very important best building practices will say 50 at the ridge and 50 at the soffits unobstructed. And many homes with terrible attic ventilation are completely mold free.

One house can suffer from major mold growth while the neighbor s home is spotless. To avoid rotting wood clumping insulation and mold your attic needs to be properly ventilated. This article series xplains the effects on buildings caused by locked soffit intake vents and we explain how blocked soffit venting causes or contributes to attic condensation moisture and potential mold contamination problems in buildings. Vents come in various styles.

Blocked soffit vents invites attic or roof cavity moisture condensation mold the photograph at page top shows an attic whose intake venting is blocked by fiberglass insulation. How to check attic ventilation. Air flows in through the soffit vents and out through the roof vents. Nope venting an attic is actually pretty hard here s how ventilation is supposed to work.

Yet many attics with ventilation far superior to the code requirements suffer from mold issues. First air enters through the soffit vents. Attics usually have a passive ventilation system in which outside air comes in through the soffit eave vents at the bottom warms up in the attic and escapes through the can or ridge vents at the top because hot air rises. The most common cause of attic mold by far is blocked or insufficient ventilation of the attic space.

Plus roofing and attic ventilation systems can protect homes from the expensive roof and structural damage caused by trapped heat ice dams moisture and mold. Attic ventilation is a two part process. A soffit vent is simply a vent installed into the underside of your home s eaves called the soffit that permits fresh outside air to be drawn up into the attic. Few areas of mold growth are more mysterious and confusing than soffit mold growth.