How To Vent Bathroom Exhaust Fan In Attic

In general you can try venting a bath vent fan down but the combination of down direction elbows and total run length may mean that it s ineffective.

How to vent bathroom exhaust fan in attic.

Although this isn t always possible in attic crawl spaces you should always insulate the duct to prevent condensation problems. Drill a reference hole draw a mark on the bathroom ceiling where you d like to install the vent fan. Duct already wrapped in insulation at home centers. The manufacturer will give guidance on the total duct length permitted.

The best exhaust fan venting is through smooth rigid ducts with taped joints and screwed to a special vent hood. You should never exhaust the bathroom fan directly into the attic. The correct way to vent a bathroom fan through an attic is to terminate the vent either to the roof or to the gable wall. Take a look at the installation manual for your fan brand and model.

Use an extra long 3 8 inch diameter spade bit to bore a reference hole through the ceiling and into the attic. Either way the vent will have to go directly to the outside and installed with a vent hood cover. You can find 4 in. When venting a bathroom exhaust fan make sure to vent the air to the outside rather than into your attic where it can cause mold and mildew to form.

Options for venting a bathroom exhaust fan include best to worst. Measure the vent fan. Through the roof or an exterior gable wall.