Q: What is the preferred method for venting the exhaust of a clothes dryer installed inside an attached garage? I have two opinions from contractors and both cost about the same, but I don’t know which to choose. The two proposals are:

One is to install the vent straight up through the roof. This involves only one 90-degree turn.

The other is to install the vent through the wall behind the dryer, which puts it inside the crawl space under the floor. The pipe would then be run to one of the crawl space vents. This requires two 90-degree turns and one 45-degree turn (venting through either of two sidewalls is not feasible in our house, leaving only the back wall or roof as options).

Please help me choose the best option. Intuitively, the vent through the roof seems the better option with only one turn. However, I have to wonder if it is wise to vent lint-laden exhaust gas straight up. Is this a valid concern?

A: Assuming the total run of vent pipe is about the same, we’d opt for venting the dryer out the (back) sidewall. Although we’ve seen dryers vented successfully through a roof, we’d be a bit leery of this route, primarily for the reasons you mention. Even though the dryer air you need to vent is warm and will rise by convection, it’s still fighting gravity when trying to vent lint-laden air vertically.

An extra “90” in the field and a “45” near the discharge location shouldn’t be a concern. We assume the two 90s are to direct the air from the dryer into the crawlspace, and the “45” will redirect the pipe to the vent for discharge to the outside. Air leaving the dryer is under sufficient pressure to move easily through the two “90s,” and the gentle bend at the discharge shouldn’t restrict the airflow.

In addition, going up means you’ll have to penetrate the roof covering. We try to avoid this to avoid possible leaks.

Show Comments Hide Comments
Sign up for Inman’s Morning Headlines
What you need to know to start your day with all the latest industry developments
By submitting your email address, you agree to receive marketing emails from Inman.
Success!
Thank you for subscribing to Morning Headlines.
Back to top
Only 3 days left to register for Inman Connect Las Vegas before prices go up! Don't miss the premier event for real estate pros.Register Now ×
Limited Time Offer: Get 1 year of Inman Select for $199SUBSCRIBE×
Log in
If you created your account with Google or Facebook
Don't have an account?
Forgot your password?
No Problem

Simply enter the email address you used to create your account and click "Reset Password". You will receive additional instructions via email.

Forgot your username? If so please contact customer support at (510) 658-9252

Password Reset Confirmation

Password Reset Instructions have been sent to

Subscribe to The Weekender
Get the week's leading headlines delivered straight to your inbox.
Top headlines from around the real estate industry. Breaking news as it happens.
15 stories covering tech, special reports, video and opinion.
Unique features from hacker profiles to portal watch and video interviews.
Unique features from hacker profiles to portal watch and video interviews.
It looks like you’re already a Select Member!
To subscribe to exclusive newsletters, visit your email preferences in the account settings.
Up-to-the-minute news and interviews in your inbox, ticket discounts for Inman events and more
1-Step CheckoutPay with a credit card
By continuing, you agree to Inman’s Terms of Use and Privacy Policy.

You will be charged . Your subscription will automatically renew for on . For more details on our payment terms and how to cancel, click here.

Interested in a group subscription?
Finish setting up your subscription
×