What is drip edge, and what does it do?
What it actually does
- Keeps water off the wood. Without it, water clings to the shingle edge, curls back underneath and soaks the deck edge and fascia. Rotted fascia and soft roof edges are classic signs of a roof built without drip edge.
- Feeds the gutters. On guttered eaves, it drops runoff into the gutter instead of behind it.
- Supports the shingle edge. Shingles overhang the metal slightly, so the edge does not droop or crack.
- Blocks wind and pests. It covers the gap between deck and fascia where wind-driven rain, insects and small animals get in.
The code requirement
The International Residential Code, which Georgia adopts with state amendments, has required drip edge at the eaves and rakes of shingle roofs for more than a decade. Many older Georgia homes were built without it, and a roof replacement is the time to add it. In insurance claims, drip edge is a line item that sometimes gets left off; when code requires it, it belongs in the scope.
Installation and cost
Drip edge is aluminum, galvanized steel or copper, usually in 10 foot pieces, lapped and nailed at 12 inches or closer. Retrofitting it under an existing roof means lifting the edge shingles, which risks breaking them, so it is normally done during a replacement. On a full replacement it is a small part of the total, and a quote that leaves it out to look cheaper is a red flag. See drip edge explained and roof flashing explained.