So the air remains warm until it exits the house.
Insulating dryer vent in attic.
Attach insulation with foil based duct tape and caulk where pipe exits the house.
In these cases it may be necessary to vent your dryer through the attic.
Cover the pipe in two to three inches of fiberglass insulation.
The international residential code allows you to run a dryer vent through the attic but you can t terminate it there.
Track the exhaust pipe from your dryer until it leaves the house.
This reduces the chance of the water condensing inside your house or dryer vent.
If venting outside isn t an option you can vent the dryer out of the attic through the roof using a special roof vent to keep rain out.
Secure the insulation with hvac duct tape.
Not all dryers will allow for this so be sure to check the owners manual to ensure it can be vented in this manner.
A dryer vent should be vented outside.
The more insulation you install the less likely you are to have condensation in the ductwork.
Doing so would fill your attic with warm moist air that could rot the framing.
Either way insulation is a necessary step when installing or repairing the dryer vent pipe particularly if it passes through a basement or crawl space.
Sometimes such as in town homes or condos it s not possible to vent a dryer through a wall outside.
Wrapping the vent pipe with insulation is a good idea.
Insulating the duct with at least 1 in.
Of fiberglass insulation will keep the duct warm during dryer operation and will minimize condensation on the duct walls.
When venting dryers for long distances use rigid metal pipe with as few elbows as possible.
You may have to cut through drywall to fully expose the pipe and be able to apply insulation.