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.

Be sure to slope the duct a bit for drainage to the. 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 best exhaust fan venting is through smooth rigid ducts with taped joints and screwed to a special vent hood. This old house general contractor tom silva shows how to properly install a roof mounted bath fan vent.

A bath vent fan duct that is too long may restrict air flow such that the fan is not functional. Do you have any solutions for dampening noise that comes through the pipe into our home. Venting through a roof vent or exhausting them in the attic could cause moisture problems and rot. A bath vent fan duct that is too short may violate the manufacturer s installation instructions may not work properly or may be drafty.

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. 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. Vent your bath and kitchen exhaust fans through the roof through a special roof hood. 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.

Connect the ductwork with sheet metal screws wrap the. See below for a shopping list and tools subscribe. 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. Here we provide specifications for recommended minimum maximum duct lengths for bathroom vent fans.

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. Bathroom exhaust fan duct length specifications. This article describes routing bath exhaust fan duct upwards through an attic or roof space or downwards through a floor or crawl space. 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.

In all cases the ducting needs to conduct the exchaust to the building exterior and needs to terminate in an animal proof vent cover.