Attic Plywood Wet

This occurs when the temperature of the sheathing drops below the dew point creating a thin layer of moisture on the substrate.

Attic plywood wet.

Reader comments q 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. Though attics are typically hot and dry a leaky roof or pipe condensation or severe weather can cause water to enter your attic. It is never a good idea to install a roof over wet plywood or any type of roof sheathing.

Water or drip marks scattered on the attic floor. If you suspect you have moisture problems in your attic check for the following indications of excess moisture in the attic. Most attics are dry plywood is a smart vapor retarder with variable permeance. In the vast majority of cases the mold growth is caused by condensation.

If your insulation particularly the cellulose on top is uniformly damp over much of the area then pretty certain it is condensation or frost forming which is not uncommon at all even in ventilated attics when the outside temp gets below about 15 or so. Buckled or damaged roof sheathing. If you have ceiling leaks only in the spring it may be that ice has been forming on the sheathing all winter and it suddenly melts when a warm spell arrives. 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.

Often this is first noticed when re shingling. There are many signs that an attic is wet. It s not a vapor barrier. Prolonged wetness will rot out the roof sheathing.

Moisture frost and ice buildup on roofing nails. Trapped water will boil when the sun heats the roof and the shingles will then have small pits where the. Moisture or frost on the roofs sheathing. Mold usually causes a musty odor and may cause staining that may be black brown gray white yellow or green.

If any moisture makes its way to the plywood the damp plywood will dry out on hot sunny days. Black mold in attics. Moist or wet insulation. Water in your attic can damage wood beams insulation and even.

Wet sheathing was found in attic area due to lack of venting.