The need to replace a small number of shingles can happen anytime during the life of a roof. Damage can result from windstorms, overhanging trees, the installation of an antenna, satellite dishes or anything that penetrates the roof surface.
When performing a repair on a small section or sections of roof, the contractor carefully removes the damaged shingles and nails, including the nails from the course above which penetrate the damaged shingles. The new shingles of the same design and colour, or best matched to existing, are then inserted and nails are reinstalled in the proper positions of the replacement shingles. Great care is taken not to lift the tabs of the existing shingles higher than necessary to hammer the nails flush. Replacement nails are also installed in the old overlying shingles where they were removed to allow the damaged shingles to be taken off.
All loosened tabs are hand sealed and all nail holes in the underlayment are filled and sealed to prevent leaking.
Sometimes, upon removal of damaged shingles, it may become evident that the wood of the roof deck is also damaged (soft or moldy) due to water penetration. Before replacing the damaged shingles, this damaged wood is cut out and replaced with new plywood to ensure that the roof deck is a stable, smooth and solid surface which will permit the new shingles to be securely fastened. If the existing roof has underlayment, new underlayment is installed over the replaced wood, followed by the installation of the new shingles.