The vent flaps are completely closed and the flange is caulked to stop air infiltration. If cold air comes into your laundry ...

Dryer vents with a mesh grate can become clogged with lint, but dryer lints without a grate invite critters in. This simple ...

You can also easily get at the exit point outside the house by removing its duct flap or duct cover. Next you need to buy a specialized dryer vent cleaning kit. I picked this one up at my local ...