Proper venting of a clothes dryer includes use of an approved connection to a vent leading to the outside of the house. The maximum distance from the location the vent exits the dryer to where the vent empties to the outside air is 25 feet, though this number is reduced by 5 feet for every 90-degree bend and 2.5 feet for every 45-degree bend, according to The Family Handyman.
Underwriters Laboratories, known simply as UL, requires a rigid vent line between the back of the dryer and the wall, according to the ASHI Reporter. However, many homes still use plastic or foil connectors. These types of connections increase the lint build-up in the line and the chances of a dryer fire. The ASHI Reporter recommends owners replace such connections immediately.
Installation of the rigid vent line requires the installer to cut the sections to length using tin snips, says The Family Handyman. The installer should use metal tape or a clamp for each joint. Longer dryer vent sections require the use of pipe straps, attached to the framing of the home, to support the vent.
When dryers take more than one cycle to dry a load, the most probable cause is the vent. Vents that are too long or clogged with lint do not allow moisture to escape from the machine. Owners should inspect the vent and clean it any time they note an increase in drying time.