White Powder On Attic Rafters

The mold usually presents as a white powder or film and many people will not realize that it is mold growth at all.

White powder on attic rafters.

It is difficult to declare this one substance over another simply based on one s senses of sight or smell. The spots can be powdery and filmy in nature. After all some mold shows up as a white powdery material but more often in a crawl space than an attic. This seems to have appeared only recently.

Although it can look similar to mildew at first white mold is more harmful since it can grow within organic materials not just at the surface. After reading your article regarding mold i checked out my 36 year old home and found very little except in the attic. I found approximately 10 percent of the roof rafters covered in spots with a white powdery substance which i assumed to be mold. The house is late victorian and the roof was re slated and felted etc about three years ago.

In the attic photograph at left we show a mix of green gray and white attic mold. Below is a photo of white mold growing on wood rafters in an attic. This lack of pigmentation is caused by the type of material that the mold is growing. White mold will remain white while other types of mold get darker over time.

The white color is caused by a lack of spore pigmentation. The attic is basically a crawl space with loose insulation between the ceiling joists. Several of the rafters running along the edge nearest to the felt have a white residue. The vast majority of attic mold is caused by humidity which is why white mold growth is common here.

When looking for attic mold trace both leak. The client will certainly expect an explanation for this white material on the roof rafters in the attic. The photo at page top shows white attic mold on the roof sheathing and rafters and some brown or black mold on the attic side of ceiling drywall where we pulled back insulation. It is quite moist and is easily wiped off leaving a black mark on the cleaning cloth.

Attic sheathing and framing.