Young roofs, early failures, and why
The defect we photograph most often in Westfield is a missing kick-out flashing. Where a roof edge runs down and dies into a wall, the last piece of step flashing has to be turned out to throw water into the gutter instead of behind the siding. Leave it off, and every rain sends a thin stream down inside the wall cavity. Nothing appears on the ceiling for years, and by the time it does, the damage is sheathing and framing rather than roofing. It is a twenty dollar piece of metal and it is the single most expensive omission in residential construction.
Second on the list is step flashing that was never really there. Proper practice is a separate piece of metal woven in with each course where a roof meets a vertical wall. The shortcut is a continuous strip, or worse, a bead of sealant along the joint. Sealant is a consumable, not a flashing: it has a service life measured in a few years, and it fails quietly.
Third is the starter course. A dedicated starter strip along the eaves and up the rakes puts adhesive exactly where the first course of shingles needs to be gripped. Substituting an upside-down field shingle puts the sealant in the wrong place and leaves the most wind-exposed course held by nails alone. It is invisible from the ground and it is the reason young roofs lose edges in ordinary storms.
Fourth is fastening. Overdriven nails cut through the mat, underdriven nails hold the course off the deck, and nails placed above the fastening line hold nothing but the shingle they went through. Any of the three voids the manufacturer wind rating, which matters enormously if you are ever trying to make a warranty claim on a young roof.
Fifth is what was cheapest on the truck. Builder-grade pipe boots are thin EPDM with a service life well short of the shingle they were installed into, so a fifteen-year-old Westfield roof commonly has boots that are cracked all the way around while the field is still in good condition. That is a repair, not a replacement, and we will tell you so.
The older half of Westfield gets none of this. Along SR 32 and in the original town grid there are farmhouses and pre-war homes with plank decking, added-on wings meeting at mismatched pitches, and the same flashing questions the rest of the pre-war metro has. Two very different jobs inside one city.