Clean all debris from the surface of the roof. This includes debris that has gathered behind HVAC units, pipes and pitch pans, and any other roof penetrations. Debris has a tendency to hold water, and water will expedite roof deterioration, especially if your roof is asphalt based such as a built-up roof or one with asphalt shingles.
If your roof has a gravel surfacing and there are some bare spots present, clean the bare spot thoroughly using a broom and a wire brush if necessary. Be sure to remove all loose dirt generated from brushing and sweeping. Spread a thin layer of asphalt roof cement (mastic) over the bare area about 1/8 inch thick. Add additional gravel and embed it in the roof cement.
Check all flashings and make sure that they are free of deterioration and holes.
Check the edge metal and make sure it isn’t separating at the seams. If it is, repairs need to be made as soon as possible.
Check for blisters in the roof. DO NOT STEP ON OR PUNCTURE THEM. These need to be patched immediately.
Clean out and rell any pitch pockets where the ller is cracked and/or shrinking.
Keep all gutters free of debris. Make sure that downspouts are draining properly by water testing them.
Trim back any overhanging tree branches.
Check all caulking and sealants on flashings and copings. Scrape and remove any caulking that is weather cracked and/or damaged. Clean the area thoroughly, using a wire brush if necessary. Reapply a polyurethane caulking such as Vulkem, NP-1, or equivalent.
Check the open valley metal for rust.
Check the mortar on chimneys and parapet walls, both in between the brick and on top. If it’s damaged or deteriorated, have it tuck-pointed.