Gas Dryer Exhaust Vent Length

Dryer vent hoses that are run in a straight line from the dryer exhaust to the outdoors provide the best ventilation and reduce the likelihood of trapped lint.

Gas dryer exhaust vent length.

Most dryer ducts are round and 4 inches in diameter. That 25 feet is based on a straight run of vent piping if there are any bends in the line. Dryer vent pipes properly called vent ducts come in a variety of materials. The maximum length of a straight run of dryer duct is 35 feet with a 5 foot deduction in length for each 90º bend and half that for 45º bends based on using a 4 inch smooth metal vent with no screws protruding into the air flow.

Dryer venting comparison chart. The international residential code irc states that the maximum length for a dryer vent is 25 feet according to the national association of certified home inspectiors website. When using a straight piece of flexible metal vent hose the maximum length allowed for safe ventilation is approximately 30 feet according to the appliance aid website. Check your manufacturer s instructions on how to install a dryer vent for longer distances.

The ductwork recommended for use between the dryer in the wall should be rigid or semi rigid modeled ducting that is 4 inches in diameter. The exhaust airflow of any whirlpool produced dryer at the maximum rated vent length is at least. Long runs of vent line with multiple bends reduce the flow of air often to the point where the dryer exhaust doesn t even reach the exhaust vent. The exhaust duct run should be as short as possible.

Clean old ducts before installing the dryer. However there are a lot of variables that can enter into the equation. Vent length for vertical installations should likely be considerably less than the. If you have to install bends you should reduce this limit by 5 feet for every 90 degree bend and 2.

The length of the run should be no more than 25 feet. Let s start with what the irc international residential code says. The vent should be as straight as possible and the code sets a limit of 25 feet on its length. The route should be as short as possible but there are other guidelines to follow when venting a dryer.

Some are flexible and others are rigid. Because all types are sold for use with dryers you would naturally assume that all are suitable for this application. Do not use plastic or thin foil ducting. The first step of installing a dryer vent in a new location is to map out a path for the ductwork.

The airflow of a dryer depends on the design of the exhaust vent. The international residential code irc section m1502 clothes dryer exhaust guidelines states that a dryer exhaust duct should not exceed 25 feet from the dryer to the exhaust vent in the wall or roof.