How to Replace Your Nasty Old Dryer Vent

3 Materials
30 Minutes

Read on to learn how to replace your dryer vent.

Shopping for a Replacement Vent

If you’re ready to replace your exterior dryer vent, you’ll want to shop for a new one that is the same size. The vent size is determined by the diameter of the dryer duct that it covers. 4 inches dryer vents seem to be the most common, but it’s always best to measure before you shop so you don’t pick up the wrong one. Amazon has a ton of selections ranging from a few dollars to around a hundred. A simple plastic dryer vent can be found for under $15.

Replacing an Exterior Dryer Vent

Remove the existing screws holding the vent in place. If your caulking is all dried up like mine was, the vent should slide right out. If not, you'll need to cut away the old caulking.

Next, it was time to remove years of caked-on caulking. A pretty simple process with a decent utility knife. Brush off the remaining caulking with a wire brush, followed by some hot soapy water to remove any remaining residue. After a few passes, most of the old caulking came off.

With the exposed dryer duct hole, I got a good look at all the lint and crap accumulated in the duct over the years. Over time this buildup of lint can be a fire hazard. This is an excellent time to clean out as much as possible.

How to Replace a Dryer Vent

First, test fit to make sure your new vent will work.

I just used caulking to hold the vent in place and avoided the screws. You can’t tell from these pictures, but this vent comes apart, so you can screw in the base and snap the cover over the top.

Simply apply some caulking to the underside of the vent all around the 4″ hole. Make sure to place the caulking where it will meet the wall and not the giant hole.

Then stick the new vent in place, and apply more caulking around the outer edges to contact the wall and the vent. After an hour of dry time, it’s ready for use.

I didn’t take any pictures of the caulking process but check my past projects and you'll find one on caulking the gaps in a kitchen.

Suggested materials:
  • Dryer vent   (amazon)
  • Caulking   (amazon)
  • Xacto knife   (amazon)
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  • William William on Jul 13, 2022

    Great project. Some dryer vents are just dryer vent caps that just fir over the existing opening. These are the easiest to replace. Other dryer vents are one piece with pipe attached which require disconnecting the pipe from the dryer on the inside then the vent can be removed on the outside. DIYers need to check what they have. What I like to do with outdoor caulk is to heat it up with a propane torch not direct flame to soften the caulk and scrape it off with a putty knife.