Roof Leaking On Underside Plywood

Roof cuts and thermographic imaging can also detect moisture in addition to other strategies.

Roof leaking on underside plywood.

Step 2 shine a flashlight along the underside of the roof and look for a hole in the roof as well as areas that are wet or have been darkened by moisture. Rotted plywood can cause a number of issues. Cracking noises can sometimes be heard when walking on the roof during wintertime as a thin layer of ice breaks he adds. Rotted plywood cannot support the weight of a roof the way healthy wood can nor can it safely grip the nails put into the roof and keep them held firm.

Some roof leaks are tough to locate. Sometimes the water shows up at a ceiling spot distant from the leak. Often water runs to openings in the vapor barrier such as at ceiling light fixtures. At the intersection of the plywood overlays the upper sheets contain black mold spreading about 2 3 up the slope.

Mold that grows on the underside of roof sheathing due to ideal mold growth conditions being present. It also dips along the edge where the moldy plywood exists. Trowel the roofing tar into the leak on the underside of the roof deck using a putty knife. Unless the roof is leaking the line you see on the roof is an aesthetic problem but the cupped plywood is putting an added strain on the shingles either side of the visible line.

Moisture causes wood to rot and rotten wood absorbs water even more readily than fresh wood. On structural concrete and possibly wood planks or plywood moisture drips may not be observed. If your ceiling has a plastic vapor barrier between the drywall and the attic insulation push the insulation aside and look for flow stains on the plastic. Mold on the underside of roof sheathing is also very common.

Push the shingle or plywood into the tar and trowel more roofing tar around the edges of the patch. Look for damp spots on the underside of your roof. Also look for a thin stream of water flowing down one of the rafters. If your roof is leaking right now go into the attic with a flashlight and some chalk to mark with while it s raining.