Ducting Exhaust Fan Through Roof

This article shows the best way to vent a hood and exhaust fan that s above the stove when you have an interior wall with cabinets above.

Ducting exhaust fan through roof.

Venting through a roof vent or exhausting them in the attic could cause moisture problems and rot. Bathroom exhaust fan duct length specifications. Use rigid metal ducting aluminum or galvanized steel with lengthwise seams facing up and joints sealed with foil tape or duct mastic or rigid plastic pipe. The bathroom exhaust ventilation fan disperses air through an opening in the fan housing which is usually 3 inches in diameter and ideally faces in the direction of the ventilation system outlet.

This article describes routing bath exhaust fan duct upwards through an attic or roof space or downwards through a floor or crawl space. So i ve installed metal duct from my bathroom exhaust fan to the gooseneck vent on my roof. See below for a shopping list and tools subscribe. We have a train that comes close to our house and when the fan isn t running and the train blows it s whistle the sound reverberates down the pipe into the house.

Bathroom ventilation fan duct routing routing a bath vent duct down out or up through an attic or roof out. I prefer to run my exhaust vents downward and out through the basement because there is no condensation inside the ducting but if you must go up through the roof use a proper. This is not an attic vent this is a roof top exhaust hood that totally prevents any moisture from the bathroom or the kitchen from causing rot problems in the attic. A bath vent fan duct that is too long may restrict air flow such that the fan is not functional.

This old house general contractor tom silva shows how to properly install a roof mounted bath fan vent. Here we provide specifications for recommended minimum maximum duct lengths for bathroom vent fans. Be sure to slope the duct a bit for drainage to the. In all cases the ducting needs to conduct the exchaust to the building exterior and needs to terminate in an animal proof vent cover.

Connect the ductwork with sheet metal screws wrap the. Do you have any solutions for dampening noise that comes through the pipe into our home. A 3 or 4 inch duct connects to the outlet on the fan housing and runs to a side wall or to the roof and connects to a vent cap that allows the. If you vent through a soffit where attic vents are often located the moisture will get sucked back up into the attic or roof venting.

The best exhaust fan venting is through smooth rigid ducts with taped joints and screwed to a special vent hood.