It is estimated that annually over 15,000 house fires are attributed to clothes dryer fires with 51 deaths, 380 injuries and 236 million dollars in direct property damage with a rise in these types of fires during the fall and winter months. What caused the majority of the fires? Lint and the type of dryer vent piping used; impairing the ability to expel the lint that the dryer lint screen doesn’t catch. It doesn’t help that most people install their dryer and never maintain the vent piping.
Most of these fires can be attributed to the lack of maintenance.
Improperly installed dryer vents and some are attributed to the type of dryer vent material used to vent the dryer. A broad range of dryer vent duct or piping is available including – flexible vinyl duct, flexible aluminum foil duct, semi-rigid aluminum duct, rigid sheet metal duct and rigid right angle periscope type duct Lets talk about each type, some of the components, recommended installation and dryer maintenance.
Dryer Venting and Components:
Flexible vinyl duct should never be used for dryer venting! It is a fire hazard! The packaging is clearly labeled
* NOT FOR USE IN DRYER VENTING * ONLY RECOMMENDED FOR BATHROOM FAN VENTING *
Flexible aluminum foil duct with high tensile steel wire helix encapsulated with an aluminum foil type material, making it easy to connect to round and oval connections. However; the interior of the duct is not smooth and the ribs along with unsupported sagging areas are prone to collect lint that sneaks past the dryer lint screen. This type of duct should is recommended to be used only for transition duct as it may become a fire hazard.
Semi-rigid aluminum ducts corrugated, flexible and can typically be stretched to an 8-foot length of pipe. Although this is much better than the plastic and foil flexible ducts it is still not smooth and can present the same issues with build up of lint, thus potentially creating a fire hazard.
Rigid sheet metal duct has a smooth interior, sections should be connected together with foil duct tape as opposed to screws as they can catch lint. This is the best option for all dryer vent ducting and if space allows for a transitional duct. Care should be made in the design and installation to limit elbows and long runs to minimize the need for maintenance.
Periscope type duct is a quick easy and safe alternative for transitional vent duct, plus it reduces the space needed behind your dryer.
Exterior dryer exhaust vents typically have an integral hood damper system is designed to prevent cold air, snow or rain from entering the home. There are vent hoods with an attached damper, louvered vents, and ones with an attached pest guard. Dryer vents should never be covered with small gauge screening to prevent birds and rodents from entry, small gauge screen will get clogged quickly possibly resulting in a vent pipe fire.
These days we see a lot of laundry rooms adjacent to the garage or near the bedrooms which can create long dryer vent runs with many turns. With long dryer venting runs and sharp turns dryer venting maintenance is critical as more lint with accumulate on the inside of a vent that is not located on an outside wall. So have your clothes dryer installed by a professional. Make sure an approved and proper vent pipe material is used and make sure that any vertical runs have no sags. The vent should never be vented inside the living space, in attic or crawl space or in combination with any other type of vent like a bathroom exhaust fan ventilation.
is crucial to reducing the potential for a dryer fire! First and always read the manufacturers’ instructions and warnings. If the period of time is excessive for clothes to dry or they come out hotter than normal you either have a maintenance or mechanical issue. Make sure the exterior vent is free and clear of any accumulated lint. Clean lint out of the vent pipe at a very minimum once a year. the correct electrical plug and outlet are used and that the dryer is connected properly. Clean the back and under the dryer with a dryer/refrigerator vent and coil brush every six months. If the dryer venting piping is visible inspect it annually. Do not store combustible in close proximity to the dryer. combustible away. If you have a gas dryer have your HVAC contractor inspect the gas lines when they service your furnace. If your dryer isn’t operating properly, efficiently or your unable to maintain it have it and the dryer venting system serviced by a qualified professional.
Statistical information from US Fire Administration