Dryer Vent Roof Cap Selection Guide
See also: Bird Guard vs. Louver | Roof Cap Selection | Installation Guide | Inspection Checklist
Overview
The termination cap is the final component in your dryer exhaust system — and the one most likely to be misspecified. The right cap for your installation depends on your wall material, climate zone, pest pressure, and whether the cap faces prevailing winds.
Key Requirements (All Caps)
- No screen of any type — mesh, wire cage, or otherwise
- Backdraft damper — gravity or spring-loaded
- Opens freely under normal dryer exhaust pressure
- Fits 4-inch duct (confirm interior diameter)
- Weather-resistant material for exterior use
For the full cap comparison by type and climate, see the Bird Guard vs. Louvered Cap guide.
FAQ
Run the dryer and check the cap from outside — it should open fully and you should feel strong warm airflow. If the cap barely opens, is visibly damaged, has a broken damper, or has significant lint buildup on its surfaces, replace it. Caps are inexpensive (5–35) relative to the risk of a blocked or damaged one.
Yes, with exterior-rated paint. Avoid painting the damper flap or the interior — paint buildup can cause the damper to stick in the closed position. Spray paint applied lightly to the exterior flange and cap body is fine.