Bathroom Soffit Vent Installation

View instructions on how to install PreVent-It soffit vents.

4" Soffit Vent for Bathroom Exhaust Fan

White 4 inch soffit vent for bathroom fan

How to Install the PreVent-It 4" Bathroom Soffit Vent

Step 1

Measure a 4.5 inch diameter minimum cut where you will install the soffit vent.

Step 2

Pull transition flex duct through opening and attach to top of soffit vent using a zip tie (not provided). For hard duct installation, pull transition duct through opening, attach duct and soffit vent, seal connection with tape or caulk (not provided).

Step 3

Push attached duct and soffit vent into hole. Attach to soffit using four (4) provided screws. Note: You will see 6 screw holes; you do not need to put screws in the 2 holes nearest the screen.

IMPORTANT: Our soffit vent is designed for use with bathroom exhaust fans only. Installing a sister joint or cross brace is recommended to prevent the soffit from sagging. For best performance, use a bath fan between 50-80 CFM and install the vent exit at the outermost edge of the soffit if possible. You should also minimize or eliminate the use of flex duct since that restricts air flow and causes louder fan noise.