Georgia Roof Guide

What do ice and water shield details look like at eaves, valleys, walls and pipes?

Short answer. Every ice and water shield detail follows one rule: each layer laps over the one below so water always flows onto the next layer, never behind it. At the eaves the membrane typically laps over the drip edge, in valleys a full sheet is centered in the crease, at walls it turns up the wall behind the flashing and siding, and around pipes and chimneys it surrounds the opening beneath the flashing.

Eave

Drip edge is nailed to the deck first, then the membrane laps over its flange, the same order the code sets for underlayment at eaves. Some membrane makers show an alternate eave detail, so follow the product's drawing. Where an ice barrier is required, it reaches at least 24 inches inside the exterior wall line, often in two rows.

Rake

Membrane or underlayment goes on first and the rake drip edge goes over it, so wind-driven water cannot get behind the metal.

Valley

A full-width sheet is centered in the valley and pressed into the crease without bridging, starting at the bottom so upper pieces lap over lower ones by about 6 inches. Underlayment on each slope laps over its edges.

Sidewall and headwall

A strip on the deck turns several inches up the wall sheathing. Step flashing or apron flashing goes over it, and the house wrap and siding lap over the flashing.

Pipe and vent

A square of membrane is cut over the pipe so it extends well beyond the boot flange on every side, then the boot goes on top, with shingles lapped according to the boot's instructions.

Chimney and skylight

Membrane goes on the deck around the full perimeter and turns up the sides, installed bottom first, then sides, then the upslope piece lapping over the side pieces. Step flashing, the backer or cricket flashing and counterflashing complete the detail.

See roof flashing explained, chimney leaks and crickets and ice and water shield in Georgia.

In depth

What are the types of roof flashing, and should old flashing be reused?Step, counter, apron, valley and kickout flashing explained for Georgia homes, what the code requires, and whyWhat is drip edge, and does a Georgia roof need it?What roof drip edge does, what IRC R905.2.8.5 requires in Georgia, how it should lap with underlayment, and hoSynthetic underlayment or felt paper: which should go under your shingles?Synthetic underlayment vs asphalt felt under Georgia shingles: performance, what the 2024 IRC requires, and th

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