Attic Sheathing Black

Mold growth on attic roof sheathing is a common issue in cool climates such as the pacific northwest.

Attic sheathing black.

Despite what your roofer would like you to believe roof leaks rarely cause significant mold problems. The other two possibilities for the stains. This occurs when the temperature of the sheathing drops below the dew point creating a thin layer of moisture on the substrate. Uniform black mold growth on attic sheathing.

If the wood is soft if it s easily imprinted when you push on it it s probably rotten. In many cases the continued wetting of the sheathing will cause it to rot but that may take several years or decades depending on the attic ventilation. Attic mold cleaner attic mold removal how to clean attic mold how attic mold gets there in the first place and what to do to help prevent attic mold. White and green fuzzy growth on osb sheathing.

If the dark surface of the wood smudges it could be mold. Condensation determining the cause of attic mold. In our roof interior attic photo at left you can see antique roof framing along with black stains and probably some mold growth from a long history of roof leaks. Mold usually causes a musty odor and may cause staining that may be black brown gray white yellow or green.

The following picture is of a long standing moisture condition in an attic where much of the roof sheathing has turned black. I m aware of the cause poorly vented bathroom fans and not well sealed fan fixtures lights wires etc. In old houses you ll usually see some spots that are stained dark or black where there was a roof leak at some point in time which was repaired but the stain remains. The mold itself may have a cottony texture but can also be velvety leathery or.

In the vast majority of cases the mold growth is caused by condensation. Even in this case in our opinion the reasons to remove and replace roof sheathing and framing would normally be based on the condition of the roof framing and sheathing not on the presence of mold or stains.