Q: I need a new roof and am in the process of getting estimates. Currently there are three layers of shingles, which I am told is the limit. I can't decide whether to tear off the entire roof, adding ...

Asphalt, wood shakes, slate and other overlapped roofings are fine until they meet an obstruction. Up against a dormer, a vent pipe, a chimney, they need flashing — a patchwork of metal sheets, and ...