Asphalt roofing shingles have a tar or synthetic asphalt coating on the back along one edge to glue the exposed edge to the shingle underneath (shingles are always laid overlapping), to prevent them from lifting in the wind or curling up over time as the asphalt dries up. In cold weather, the tar will remain solid, so the shingles must either be heated or secured with some other type of glue.

sample ref (with photos):


Work carefully to break the bond to release the shingle tabs (Photo 1). Work from a stable ladder centered on the doorway and release only those tabs along the third course of shingles up from the eave. To avoid breaking the tabs on older, brittle shingles, lift them only 2 to 3 in. On newer roofs where the shingles are more pliable, fasten the diverter in place using both silicone (Photo 2) and roofing nails. Space the nails every 2 ft. under the shingle tabs. Caulk the nailheads with silicone.


1. Lift the shingle tabs that are centered over the porch stoop by gently pushing the flat end of a pry bar under each tab. If the asphalt sealant holding the courses of shingles together won’t release, apply more force to the pry bar by punching the back of the bar using your palm or tapping the bar lightly with a hammer. Work in temperatures of about 40 to 70 degrees F.
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