One of the greatest -- and possibly most overlooked -- cause of house fires today is an improperly installed dryer vent. Clothing dryers are undeniably one of man's greatest inventions (according to most busy homemakers, anyway!), and we would guess that many never give much thought to their safety.
So, what is the purpose of a dryer vent, anyway? A dryer vent essentially exists to get all of the byproducts of a clothes-drying-cycle safely out of the house. In other words, it transports all moisture and lint from your clothing to the outside world. In order for this to happen, it must be made of materials that meet all safety standards and properly installed.
First and foremost, your dryer should vent to the outside -- never to a chimney, crawl space, attic, or other vent. The best and safest vent material is rigid metal (rather than the flexible plastic or metal commonly used in the past) because it is non-flammable, it cannot become easily crushed, it doesn't trap lint, and it allows for maximum airflow. Next, your dryer's vent must be as straight as possible, because any kinks and/or turns will inhibit airflow and thus increase the risk of a fire or other problem. All joints must be secured with metal tape and should not contain any rivets or screws, as these encourage the trapping of lint within the duct. As a final consideration, vents should be at least 4"in diameter and no more than 35 feet long.
Dryer Vent Maintenance
It is very important to perform regular maintenance on your dryer and dryer vent in order to prevent serious safety issues from cropping up. Perhaps the easiest step you can take is to clean out your dryer's lint screen every time you use it. This will increase the dryer's efficiency, prevent it from overheating, and keep it free of highly flammable lint. It is a good idea to vacuum the lint screen's cavity and clean behind your dryer on a monthly basis, as well.
Another way to ensure a safe clothes-drying experience is to periodically clean your dryer's duct and air vent on the outside of your house. If you go outside while your
dryer is running, you can check for blockages in the vent or duct by simply feeling for airflow in front of the vent. You should feel warm, moist air exiting through the dryer vent. If you don't feel warm air, you'll need to pay special attention when cleaning your duct work, because there is likely a blockage somewhere between your dryer and its outside vent. After checking for blockages, you can give your vent and duct a thorough cleaning by following the steps on the diagram shown above.
As always, if you have any concerns regarding the safety or construction of your dryer vent, it is best to contact a professional as soon as possible. House fires are no laughing matter -- better safe than sorry!