Can you soffit vent a dryer, and is there a best soffit dryer vent?
Short answer. Venting a dryer through the soffit is generally a bad idea and often not allowed: the warm, lint laden exhaust tends to get pulled right back into the attic through nearby soffit vents. The code's default rule keeps dryer terminations at least 3 feet from openings into the building unless the dryer manufacturer says otherwise, and vented soffits are openings into the attic.
Why soffit terminations are a problem
- Recirculation. Attic intake vents are designed to pull air in at the eaves. A dryer outlet a foot away feeds them hot, humid air and lint.
- Moisture. A load of laundry releases a lot of water vapor. Drawn into the attic, it can condense on the decking and feed mildew, especially in winter.
- Lint buildup. Lint collects in soffit vent screens and on the insulation, which both blocks ventilation and adds a fire hazard.
- Code. Termination must be outdoors with a backdraft damper and no screen. Some code editions specifically mention keeping distance from ventilated soffits, and many inspectors flag soffit terminations under any edition.
About "soffit dryer vent" products
There are soffit mounted exhaust terminations sold for bath fans and dryers. Even the best of them only work if the surrounding soffit is solid, not vented, for the required distance, and if the dryer manufacturer allows that termination. In practice, a sidewall vent is almost always the better choice.
Better options
- A sidewall termination with a dryer rated hood and damper, as short and straight as possible.
- A roof termination with a dryer rated cap, if the dryer manufacturer allows it and the run is within length limits.
- Rerouting the duct during a remodel if neither works today.
If your dryer already vents to the soffit, check the attic near that spot for lint and damp insulation. Learn more in roof ventilation basics and attic heat and shingles.