Dryer Vent Hose Through Attic

The international residential code allows you to run a dryer vent through the attic but you can t terminate it there.

Dryer vent hose through attic.

Metal duct going vertically from the dryer through the second floor ceiling. Keeping a clean dryer vent is much easier when you can safely reach the exit. Sometimes such as in town homes or condos it s not possible to vent a dryer through a wall outside. Seal the ceiling penetration so that the duct can expand in length as it heats up during use a standard roof boot such as you d use to flash a vent pipe would work.

When venting dryers for long distances use rigid metal pipe with as few elbows as possible. Doing so would fill your attic with warm moist air that could rot the framing. The sheet metal duct is cooled by the outside air in the attic. It should go out through a wall or the eve of a roof.

At less than 5 1 2 above the roof plane it is also low profile for minimal visibility. The maximum length of the duct shall be reduced 2 5 feet for each 45 degree 0 8 rad bend and 5 feet for each 90 degree 1 6 rad bend. These terminals need to be cleaned on a regular basis to prevent lint buildup. In these cases it may be necessary to vent your dryer through the attic.

The photo below shows an accumulation of dryer lint in an attic after years of the vent terminating in it. This code requirement is usually referred to when a homeowner wants to install air conditioning ducts from the house hvac system to the garage but also applies for dryer ducts. This causes the steam from your dryer. The maximum developed length of a clothes dryer exhaust duct shall not exceed 35 feet from the dryer location to the wall or roof termination.

No a dryer should not be vented through the roof. Venting a dryer into an enclosed space is never a good idea. A vertical dryer vent is typically a problem because it acts as a moisture condenser. It should have a cap on the end with a flapper so that animals cannot get in.

Not all dryers will allow for this so be sure to check the owners manual to ensure it can be vented in this manner. Vent the dryer with 4 in. Be careful you don t cut through any studs electrical wires or pipes in the process. A dryer vent should be vented outside.