How to Install Roof Flashing

Step, Wall & Chimney Flashing Techniques

This guide explains how to install step flashing at sidewalls, continuous wall flashing at headwalls, and counter-flashing at chimneys and skylights. Each step flashing piece is woven between shingle courses with the upper edge tucked behind siding or counter-flashing. Apron flashing covers the front of chimneys and headwalls. The guide includes diagrams for brick chimneys, dormers, skylights, and pipe penetrations. Properly installed flashing is the difference between a 25-year roof and a 5-year leaker.