Technical Jargon: Boot Flashing

Advisory Report - April 2004

Technical Jargon:  Boot Flashing

“Technical Jargon” is a forum in used to provide more information on terms commonly seen in U.S. Inspect reports.

Boot flashing, or, vent boots, are a specialized type of flashing used for cylindrical non-flue vent penetrations.

Flashing is an important part of every roof. Most flashing is pretty simple, a piece of metal angled to fill the gap between two different objects or surfaces on the roof. But when it comes to cylindrical penetrations in the roof, you can’t simply bend a piece of metal around it. For these situations boot flashing is used.

When flashing a vent, there are actually two pieces necessary to create an adequate barrier. First, a flange fits around the vent and covers the area around the base of the vent. The boot then fits snugly around the pipe and into the flange, creating the water tight seal. There are two commonly used types of boots, lead and neoprene (rubber). A lead boot extends to the top of the plumbing vent termination above the roofline and is then folded back into the top of the pipe to ensure a seal. A neoprene boot fits tightly enough around the pipe and into the flange to create the seal.

Click here for more information about flashing and roof structures.

Contributed by Justin Gore
Quality Assurance Supervisor
U.S. Inspect, LLC

Diagrams used under license from The Illustrated Home, © 1998 Carson Dunlop & Associated Ltd.