The most common cause of attic mold by far is blocked or insufficient ventilation of the attic space.
Attic mold soffit vents.
Questions answers about the impact of blocked soffit vents on building roof cavity or attic moisture condensation ice dam leaks mold.
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.
How to check attic ventilation.
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.
Air flows in through the soffit vents and out through the roof vents.
To avoid rotting wood clumping insulation and mold your attic needs to be properly ventilated.
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.
Attic ventilation is a two part process.
If you see dampness or frost you need better roof ventilation and some attic vents.
Grab a flashlight and inspect your attic during the winter.
Vents come in various styles.
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.
Almost all homes are fitted with some kind of roof vents at the peak of the roofline be it individual roof vents hip roof ventilation and many homes have gable vents as well.
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.
Venting a homes attic is a very important best building practices will say 50 at the ridge and 50 at the soffits unobstructed.
For the best results place roof ventilation near the roof s peak and soffit vents in the eaves.
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.
And many homes with terrible attic ventilation are completely mold free.
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.
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.
First air enters through the soffit vents.
Unlike growth in other areas of a home soffit growth does not appear to follow any reliable pattern.
Nope venting an attic is actually pretty hard here s how ventilation is supposed to work.