The 2020 National Fire Protection Association (NFPA) statistics show that there are between 15,000 and 17,000 fires every year in the United States due to clothes washers and dryers. Clothes dryer fires injure around 380 people and are responsible for around 50 deaths per year. The leading cause (34%) of these fires is a failure to clean or replace defective dryer vents. During home inspections, our HomePro Inspections professionals have found many dryer vents that are plugged, damaged, use improper materials, or are improperly installed.
My personal story.
Several years ago, long before I became a home inspector, my wife complained that our dryer was starting to take way too long to dry clothes. Sometimes it would take two cycles to dry jeans. She wanted a new dryer. I thought to myself, “This home is only two years old; how can the dryer be giving us problems already?” I did some troubleshooting and found the problem; the dryer was fine, but the dryer vent was completely clogged with lint.
In my previous homes, the dryer was on an outside wall, less than a foot from the exterior. In this new 2-year-old home, the dryer was in the middle of the main floor. The dryer vent entered the wall, turned downward to the basement, turned horizontal for about 8 feet, turned horizontal again, and ran about 20 feet to where it exhausted to the exterior.
I disassembled the dryer vent and cleaned it with a dryer vent brush. The result was about one and a half five-gallon pails full of lint. Needless to say, the dryer started to work perfectly. With this in mind, we clean the vent annually.
The use of improper materials is a problem.
During our home inspections, we often encounter various issues that can contribute to a potential dryer fire, with improper venting materials at the top of the list.
What is the proper dryer vent ducting material? According to the Minnesota Mechanical Code (504.6), “Exhaust ducts for domestic clothes dryers shall be constructed of metal and shall have a smooth interior finish... and shall be a minimum nominal size of 4 inches (102mm) in diameter.”
At the hardware or big box store, you will find a wide selection of dryer venting products. While some appear capable of doing the complete job of venting a dryer, their main function is to create transition pieces, not the entire run from the dryer to the exterior of the home.
One kind is a “slinky-type” tube of shiny mylar material. This product can be problematic because the inner surface is corrugated (rough interior finish) and does not allow for smooth airflow. The disrupted airflow typically results in accumulated lint and eventual plugging.
Another product is a stretchable, flexible aluminum tube. Like the shiny mylar material, this tubing also has a rough interior finish that is susceptible to lint accumulation and plugging.
Damaged or crushed materials will cause big problems.
The lightweight construction of the flexible tubing discussed above makes it susceptible to damage. During home inspections, we frequently discover crushed or torn venting materials behind dryers.
Remember, these materials are meant to be used to create short transition pieces. In a situation where two metal dryer pipes don't match up, you can use one of these materials to connect them. Unfortunately, these products come in packages that contain several feet of material. Most of the time, however, instead of cutting the needed length for the transition, people just connect the ends and leave an 8-foot “anaconda” stuffed behind their dryer.
Summary
You, as a homeowner, can do your part to prevent a dryer fire from occurring in your home by performing proper installation, cleaning, and maintenance. Even if your dryer seems to be running fine right now, it’s better to be safe than sorry.
Use only UL-approved materials, use them properly, and follow your local codes when replacing dryer vents.
Clean the lint trap in your dryer after every load, and occasionally check the dryer vent exhaust on the exterior of your home to remove any lint or buildup. Pay attention to dryer cycle times. And, most importantly, have your dryer vents cleaned at least once annually to ensure the entire vent system is clean and lint-free.
At HomePro Inspections, our home inspectors are trained to inspect all areas of the home. Your home inspection report documents any issues found and recommends their resolution by you or a qualified professional.
Visit our website to learn more or to schedule your home inspection in the Rochester, Owatonna, and Faribault, MN areas. Contact us today at (507) 202-8942 or by email, and you can use our convenient online “Schedule Now” feature to schedule an appointment.