How the Whippany corridor and the tree canopy age a roof here
East Hanover sits in the low, wooded ground along the Whippany River, and the air here holds moisture in a way that matters to a roof. Mornings stay damp well into the day under the heavy shade of oaks and maples that were planted or left standing when these neighborhoods went up. Shade is comfortable on the ground and hard on a roof. The north and tree-side slopes never get the long stretches of direct sun that dry a shingle field out, so moss and algae take hold in the granule surface, lichen creeps into the laps, and the whole slope stays just wet enough long enough to soften the asphalt and rot the wood beneath any spot where the water is no longer being shed cleanly.
Then there is the litter. A canopy that thick drops a constant load of leaves, twigs, helicopter seeds, and acorns, and most of it lands in exactly the wrong places, the valleys and the gutters where the roof concentrates its drainage. A valley packed with wet debris is a dam. Water that should be racing off the roof instead backs up, sits, and finds its way under the shingles and into the decking. We see more roofs in East Hanover ruined by a clogged valley than by any storm, and the worst part is that it is silent. The ceiling stain shows up a year after the damage started, by which point the plywood underneath is already soft.