The hole in the wall for the dryer duct is a little big, and I suspect that mice entered through the gap. They are now warm and comfortable under our dishwasher.
What is the best way to seal the gap? I get the impression that expanding foam is messy and difficult to remove. I’d rather use something reversible. Is there some kind of plate that will fit snugly around the duct and screw to the wall?
Janet
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Replies
Janet
What's the wall surface?
Is there a boot on the end of that pipe?
or is this on the inside?
If so, they usually sell a plastic trim along with the boot kit.
Or, cut a 4" plus hole in some metal -unbent step flashing for instance, or other easily cut metal. Screw that around the pipe.
The wall has wood shingles on the outside, and there is a boot that does not fit tightly against the wall. I didn't know it was called a boot (to me, a boot is the trunk on a Jaguar). Home Despot had several kinds but didn't sell the trim separately. As it is old, battered, and fits poorly, I decided to replace the whole thing.
At first I was going with a sturdy boot of steel, but the guy in the paint section didn't know how it should be primed for painting (all the Rustoleum metal primers said "not for use on galvanized metal"). So, I went with a flimsy aluminum-and-plastic boot as a stopgap.
But for future reference, how DO you prime galvanized metal?
Caught three mice in four days, but none for a while now. The new boot is doing the job. Thanks!
Janet
What worked for me and galvinized........
Wipe down with white vinegar, let dry, heck..........scuff it up a bit with sandpaper.
Paint or prime. One that says for metal.
For starters you can just stuff it tightly with fiberglass. Add a little steel wool if the mice are apt to gnaw through the glass.
Then you can finish it with whatever sort of metal (or even plastic) plate you can devise. Best is to take two roughly square pieces of stiff flashing 6-8 inches wider across than the diameter of the duct, cut U-shaped slots in them, then slide them on from both sides, or (especially if exposed to the whether) install one from the bottom and the second over it from the top, so the top one laps over the bottom one like a shingle. Caulk the top edge and right around the duct.
Foam CAN be messy and difficult to remove... which is why you want it for that gap.
The "Gap and Crack" formula (not the door and window) has a tube that can be stuck into the hole before you press the spray button. This will help you control the fill. It expands about another 50%, so don't fill it until it is coming out - just fill it until it's close to coming out. After it expands and hardends, you can trim it back with a razor blade, or even sand it smother(er). Fill the poors with spakle.
dryer duct gap
I suggest that you fill the gap with some wire mesh, and some gap and crack spray foam. Finally pick up a product at your local home center called Dryer Dock. It's a plastic quick connect or disconnect rim that allows easy access to your dryer duct when you need to remove the potentially flammable lint buildup inside the duct. The Dryer Dock connector hides the gap, and creates a finshed look.