My roofer installed a metal roof on my house. However he did not install a drip edge. Rather, the metal roof overhangs the wood beneath by about an inch. I think this is inadequate because when it rains however the edge of the plywood roof is wet. Is the installation of a drip edge standard? If there is no drip edge by how much should the metal overhang the wood? Thank you for your help. I spent alot of money installing this roof and I am quite distressed by the poor result.