Water Dripping Behind Gutters
Tom Silva explains the risk of letting rain water run off your roof behind the gutter
Water from our roof's drip edge is going behind the gutter. Should we be concerned? — Beverly and Brooks Riley, Parkville, Md.
I see this problem a lot, usually because roofers push the lower leg of the metal drip edge tight against the fascia board. It looks neat, but when it rains, surface tension pulls the water around the bottom edge of the leg and onto the fascia, causing drips behind the gutter.
Drip edge should be installed so there's a gap of about ½ inch between the lower leg and the fascia board. Water can't bridge that gap, and the fascia has a chance to dry.
You should fix this. Moisture trapped behind the drip edge and gutter can rot out a wood fascia and attract termites and carpenter ants. But if reinstalling the drip edge isn't in your budget, then block the water's path by sliding metal flashing up behind the drip edge and place the flashing's lower edge inside the gutter.
— TOH General Contractor Tom Silva