What Every Wisconsin Homeowner Needs to Know about Rooftop Dryer Exhaust Vents

What Types of Dryer Vents are Necessary for Your Home

When clothes dryer first became readily available for home use, they were installed against or near an outside wall in the basement or on the first floor. In most cases, the dryer vent line was 10' or less. This enabled a very efficient flow of dryer exhaust through the vent line. The outside exhaust vent was readily accessible, so the lint that collected there over time could easily be cleaned by the homeowner.

Over the years, building trends have resulted in dryers no longer being situated near outside walls. Since the early 2000s, the trend in home building has been to put laundry rooms in the center of the house, and often on the second floor. The idea was to make it more convenient for homeowners to access the laundry room from the most lived-in parts of the house. Condominiums and other multi-family housing also have laundry rooms located in central areas where routing the vent line up to the roof is the only option.

Here’s why this is such a problem:

• The longer the dryer exhaust vent line, the greater the chances the hot air from the dryer will not be fully expelled outside, especially when lint collects inside and obstructs the flow of exhaust. Instead, it remains inside the vent line and backs up into the dryer—causing it to take longer for clothes to dry.
• Exhaust vents located on the roof are difficult to access. Few homeowners are willing to climb up on the roof to inspect their exhaust vent and clean it out, if necessary. As you can imagine, no one in a multi-story condominium is going to go up on the roof to check the exhaust vents. So, when they’re clogged, no one even realizes it.
• In winter, warm air released through a dryer exhaust vent on a roof causes snow to melt. The water rolls down the roof and freezes farther down, causing an ice dam. Over time, it becomes large enough to cause leaks in the roof as the ice starts to melt.

Many homes and condominium buildings have poorly designed roof vents, and even vents that weren’t designed to be used for dryer exhaust. They typically don’t have a large enough opening to adequately vent dryer exhaust, and many have bird/rodent guards installed. These cage like covers may keep pests out, but they become easily clogged with lint particles that are expelled along with the dryer exhaust.

Below are some examples of lint-clogged roof vents we’ve come across. As you can see, the common thread here is lint obstructing (or completely blocking) the exhaust. None of these roof vents were designed to be used as dryer exhaust vents.

What is the best exhaust vent for a roof?

Dryer Jack rooftop exhaust vent, model 486 with extra height to clear snow accumulation on roof.

Dryer Vent Wizard only installs the Dryer Jack roof vent. These vents were specifically designed to maximize air flow and they are the most efficient roof vent design available today. Testing has shown the Dryer Jack causes almost no reduction in airflow. We usually install their Model 486, which is a little taller than their standard roof vent to allow extra clearance for snow.

Do you really need to have your rooftop dryer exhaust vent replaced?

The short answer: if it’s anything other than a Dryer Jack roof vent, yes.

If you're not concerned about the risk of a lint-clogged exhaust causing mold growth or, worse yet, a fire, by all means keep the exhaust vent you have.

Of course, perhaps you're able and willing to climb up onto your roof on a regular basis to clean out the lint that gets stuck in an improper dryer vent exhaust. If not, though, you’re much better off having it replaced with a vent specifically designed for dryer vents.

Contact the Dryer Vent Wizard of Wisconsin nearest you for an estimate on rooftop dryer vent exhaust replacement.

Northeast Wisconsin: Fond du lac, Sheboygan, Manitowoc, Kewaunee and the Fox Valley Counties. 920-644-3797

North Milwaukee: All locations north of Highway 94 in Dane County, Waukesha, Milwaukee, Ozaukee, Washington and Dodge counties. 262-757-8368

Southeast Wisconsin: All locations south of Highway 94 in Dane County, Waukesha, Milwaukee, Walworth, Racine and Kenosha counties.  262-312-1991. For property managers and condo associations, call 262-501-5240.