How to Repair Rotted Wood on a Roof

Replace damaged wood decking under the shingles for small areas of rot and spare the expense of a new roof.

A stained ceiling or dripping water often signals a leaky roof. These symptoms, however, indicate the roof has experienced damage for some time. Ceiling stains mean water has worked through the layers of shingle, roof decking and insulation and soaked the ceiling’s sheetrock. Perform regular inspections of your roof to discover such problems before they lead to a stained ceiling. Once the damage is done, however, avoid replacing the entire roof, if possible, and repair the rotted section.

Step 1 – Wait for a rainy day, and after 30 minutes of rainfall, inspect the interior of your home to narrow down the source of the leak. Check the ceilings and attics, if necessary, to identify any discoloration. Follow the stains through the sheetrock and insulation until you reach the discolored and/or rotted area on the roof decking.

Step 2 – Wait for a clear day to carefully make your way to the rooftop and find the actual spot where the water flows though the roofing material. Look for clues like shingles showing signs of blistering, buckling or curling. Check for any loose material or worn areas around chimneys, pipes and other penetrations. Finding lots of shingle granules in your gutters is another sign of damaged shingles.

Step 3 – Remove the shingles and roofing felt, or other roofing material, from the area around the leak’s source. Lift and remove the old shingles with the pry bar using care to leave the healthy shingles intact. Pull out the removed shingle nails. Cut out the rotted wood decking, in one piece if possible, with the saw. Cut the rotted area from the attic, if possible, to avoid cutting the roof rafters.

Step 4 – Measure the piece of removed wood decking and cut a sheet of OSB or other roof decking to match the measurements. Replace the decking and nail in place along the piece’s edges with nails placed every 4 to 6 inches. Make certain the nails sink into the roof rafters.

Step 5 – Place the bitumen tape along the exterior seams of the new decking piece. Replace the roofing felt, overlapping the new on top of the old felt, and secure in place with the plastic cap nails. Lay the new shingles according to the established pattern and attach with galvanized roofing nails. Head to the attic and apply subflooring adhesive between the new decking piece and the roof rafters to provide extra strength. Replace insulation and sheet rock, if necessary.

Map Ashburn Results


More Good Stuff on