Black Spots On Plywood In Attic

Are these just stains.

Black spots on plywood in attic.

Or is a little bit of mold okay if the sheathing is drying out each summer and it. There did not appear to be any mold or mildew on the surface but i could see black spots. Mold growing on the sheathing in your attic is a serious problem that shouldn t be ignored. Black marks on ceiling.

Last winter i took a look into the attic and noticed black stains and water marks on a portion of the sheathing material. After a long winded background my question is. When moisture condenses on plywood roof sheathing repeatedly or continuously the wood will turn black. If the dark surface of the wood smudges it could be mold.

The plywood and the insulation felt dry but there were definitely a few sporatic black spots of mold. It is also a potential breeding ground for black mold because it is often hot and humid and there is a potential for water seepage. The black attic mold shown here confirms that this attic had a serious venting and moisture problem including moisture from sources lower in the building. This can be caused by the action of fungal growth and molds and the affect they have on the tannins in the wood.

The attic is one of the parts of the home that is not frequently visited especially if it is difficult to access. Uninsulated attic hatches are a common spot where heated air escapes into an attic. I have surface mold on the sheathing in my 1982 vintage 12 6 pitched attic. Mold is not always easy to see most of the time it is of a different color than the material it is on but if you have painted the osb a dark color it may be difficult to spot.

When this seepage occurs it can often go. Do i have a minor or major problem here. This summer i cleaned the portion of the black stain with a dry mop as much as i could reach from the hatch. Black mold in attics.

In this photo of very dark mold in an attic in a wet attic mold which we found to be brown in the microscope looked black on the plywood. I m aware of the cause poorly vented bathroom fans and not well sealed fan fixtures lights wires etc. If the wood is soft if it s easily imprinted when you push on it it s probably rotten. The following picture is of a long standing moisture condition in an attic where much of the roof sheathing has turned black.

The house was thirty years old. Do i need to rip the siding and sheathing off and put a rain screen on. Black flex gas line. This was on the under side of the roof decking.

No moisture detected and the roof is new. Stains on the interior walls. Use a flashlight and shine the beam along the surface of the osb this will reveal the mold no matter what the color due to it being three dimensional.