Dryer vent systems constructed of vinyl or flexible foil are not safe; this type of venting is really designed for use in bathroom exhaust fans. Dryer exhaust ducts must be constructed of rigid metal with smooth interiors to promote maximum air flow. Exhaust ducts should be connected with foil tape, not sheet metal screws which protrude to the inside, catching lint and causing dryer exhaust leaks.
Length of the Dryer Exhaust Duct
The length of dryer exhaust ducts should not exceed 25 feet from the back of the dryer to the vent outdoors. This recommendation applies to straight ducts; reduce the length by 2.5 feet for each 45-degree bend and 5 feet for each 90-degree bend. Bends restrict air flow.
The dryer exhaust ducts must terminate outside, not into the attic or crawl space. The vent should be located at least 3 feet from any entrance into your home. When dryers are vented into the attic or crawl space they allow mold to grow and cause wood decay. Mold in your home is also a health hazard, causing upper respiratory problems. If you have a gas dryer you should be aware that the dryer vent system is also removing gas by-products, including carbon monoxide from your home.
Another common mistake found when inspecting dryer vent systems is a screen at the termination point. Screens allow lint and dust to build up, reducing air flow. The vent should have a back draft damper or flaps that open and expel air when the dryer is running.
It is recommended that you have a dryer exhaust specialist inspect your dryer vent system to be sure it is properly installed to meet city, state and manufacturer's safety codes. In addition, professional dryer vent cleaning is recommended at least once a year; more often if you have a large family and are doing more laundry than the average household.
Dryer Vent Wizard provides dryer vent cleaning, dryer vent repair, dryer vent installation and all dryer exhaust services to make clothes dryers operate safely and efficiently. Dryer Vent Wizard has made a commitment to make 1 million clothes dryers safer and greener by the year 2010. Visit http://www.dryerventwizard.com to learn more.