Black Stains On Plywood In Attic

While the black stains are either mould or just black dust from attic insulation settled on the.

Black stains on plywood in attic.

This type of mold growth will not smudge or wipe off. While the plywood remains largely unaffected. I m aware of the cause poorly vented bathroom fans and not well sealed fan fixtures lights wires etc. You can remove small amounts of mold covering 10 square feet or less of attic sheathing yourself but if the mold growth covers more than 10 square feet you should contact a.

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. In winter moist air is transported from the heated area of the home into the unheated attic space where it not only settles on the wooden rafters and plywood roof sheathing but also melts the snow on the roof leading to ice dams. Black mold in attics. This summer i cleaned the portion of the black stain with a dry mop as much as i could reach from the hatch opening.

If the dark surface of the wood smudges it could be mold. Some spots are just patches here and there and others are big areas. I have surface mold on the sheathing in my 1982 vintage 12 6 pitched attic. Often this is a sign that the plywood has been replaced recently.

When moisture condenses on plywood roof sheathing repeatedly or continuously the wood will turn black. Attic feels excessively hot or stuffy attics should feel breezy if they are properly ventilated. Notice the dark staining in the first picture. 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.

I have obvious moisture stains in the attic and the roof. You have mold that should be removed. 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. Last winter i took a look into the attic and noticed black stains and water marks on a portion of the sheathing material.

First let s look at the source. The following picture is of a long standing moisture condition in an attic where much of the roof sheathing has turned black.