Don’t Vent Your Clothes Dryer Through the Roof

Don’t Vent Your Clothes Dryer Through the Roof

By In Dryer Vented Through Roof On June 24, 2014


As soon as I’m in charge, there will be no more venting of clothes dryers through the roof.  I think the roof is a stupid spot to terminate clothes dryer vents because it’s difficult to clean and it’s a major contributor to ice dams.  Clothes dryers should be vented through the side of the house, preferably within reach from the ground.

Ice Dam Contributor

When bath fans and clothes dryers vent through the roof, they melt a bunch of snow.  After the snow melts below the vent, it’ll probably freeze again farther down on the roof.  If this happens enough, an ice dam will form that’s large enough to cause roof leaks.  These areas of the roof are especially susceptible to roof leaks because there is no ice and water shield installed in these locations.  I blogged about this earlier this year: Advanced Ice Dam Prevention.

Tough to Clean

As I mentioned in my blog post about keeping your clothes dryer safe, the terminals for clothes dryers need to be cleaned on a regular basis.  These terminals can get extremely dirty with lint over time, and eventually, the dampers get stuck open.

dryer terminal in need of cleaning

Eventually, the terminal will get so filled with lint that air flow is obstructed, which will reduce the performance of the clothes dryer and could actually cause a fire.  Cleaning the dryer terminal at old houses is usually a piece of cake; the lint can just be wiped off and pulled out by hand.  The dryer terminal is easy to access at these houses because laundry rooms used to be installed in basements or on the first floor… but not any more.  The standard for new two-story homes for nearly the last ten years has been to install the laundry room at the second floor.  When that happens, where does the dryer duct go?  Through the roof, of course.  Most of the time.
Dryer duct through roof
This arrangement will work fine at first, but just like dryer vents that go through the side of the house, the terminal will eventually get clogged with lint.  The photos below are from a recent inspection of a 2007 built home in Plymouth that had a badly clogged dryer vent terminal at the roof.
Dryer Terminal at roof
Clogged dryer terminal at roof
While I usually don’t perform repairs or home maintenance chores at homes while I’m inspecting them, I couldn’t help but pull some of the lint out.  There was enough to start several campfires.
Ball of lint pulled out
If you’re having a home built, try to have your builder terminate the dryer duct at a location that makes sense.  In my humble opinion, dryer vent terminals should be accessible from the ground.
If you already have a home with a dryer that terminates at the roof, be sure to have the terminal cleaned on a regular basis, and consider having the terminal replaced with a  DryerJack terminal.  Get the extra clearance model 486.  I don’t have any personal experience with these, but I’m a fan of the company that makes them: In-O-Vate Dryer Products.   They make a bunch of products designed to make clothes dryers perform better.  I tested out their DryerFlex product a couple of years ago and blogged about it here:  DryerFlex: A Superior Dryer Transition Duct.

Author: Reuben SaltzmanStructure Tech Home Inspections

          


About the Author

Reuben

Reuben is a second generation home inspector with a passion for his work. He grew up remodeling homes and learning about carpentry since he was old enough to hold a hammer. Reuben has worked for Structure Tech since it was purchased by Neil in 1997, and is now co-owner of the company. Reuben’s favorite customers are the ones who have a lot of questions; he grew up thinking he was going to be a school teacher because he enjoyed teaching others so much. In a sense, that’s a lot of what home inspections are about, so Reuben truly does what he loves. Reuben has an A.A. degree in liberal arts and has attended most of the Building Inspection Technology classes at North Hennepin Community College. Reuben and his wife are the proud parents of two young childen, Cy Alexander and Lucy Nicole, and have a German Shepherd named Stanley. With two young children Reuben doesn’t have much free time, but he still tries to play disc golf as often as possible during the summer. Reuben lives in Maple Grove, MN. Professional Qualifications / Memberships: *ASHI Certified Inspector *President, ASHI Heartland Chapter *Member, Minnesota Society of Housing Inspectors (MSHI) *Licensed Minneapolis Truth-in-Sale of Housing Evaluator *Licensed Saint Paul Truth-in-Sale of Housing Evaluator *Licensed Maplewood Truth-in-Sale of Housing Evaluator *Licensed Hopkins Truth-in-Housing Evaluator *Licensed Robbinsdale Point of Sale Evaluator *Affiliate Member, Southern Twin Cities Association of Realtors

3 Comments

  • Bob 2 MONTHS AGO

    Also DO NOT terminate near AC condensing units !!

  • level 380 3 MONTHS AGO

    Great advice re roof vent.... The other option is to use a dryer that doesn't need venting at all. A condenser dryer doesn't need outside air vent as they capture water in a container or a pipe out to a drain. So if you have a roof vent and your dryer dies, think about changing the type of dryer!

  • Brian A Dawson 4 MONTHS AGO

    Great blog post. I am always amazed at the number of home inspectors that don't give the dryer venting a second look let alone "inspect it". Kudos to putting this topic out there for people to read. More homes are suffering from blocked and restricted dryer vents but few people know they need to provide periodic maintenance to keep the air moving properly. This not only saves money, but can save significant damage to your dryer and home.