# How to seal wall around vent



## mike22 (Oct 1, 2016)

i have a direct vent gas fireplace. The vent goes through the plywood wall but the hole in the playwood is an inch or two bigger than the pipe so there's a gap. We've been having mice get in our house in that area. How can I seal around the gap? The fireplace was installed when we bought the house and I think it was a DIY job so that's probably why there's the gap. Is it something I can fix myself? I have to do something keep the mice out. Thanks.


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## DAKSY (Oct 2, 2016)

There is a component called a wall thimble that is missing. The plywood around your vent needs on" clearance on the sides & the bottom & a 2"
clearance on the top. Go to your local hearthshop or look on line for the correct component. It is of a two piece construction & will require disassembly of some of your venting, along with enlarging the existing hole & some additional framing. Once that is installed that gap will be reduced to less than 1/4" on all sides. You can seal that with RTV silicone or adhesive-backed tape gasketing.


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## mike22 (Oct 2, 2016)

DAKSY said:


> There is a component called a wall thimble that is missing. The plywood around your vent needs on" clearance on the sides & the bottom & a 2"
> clearance on the top. Go to your local hearthshop or look on line for the correct component. It is of a two piece construction & will require disassembly of some of your venting, along with enlarging the existing hole & some additional framing. Once that is installed that gap will be reduced to less than 1/4" on all sides. You can seal that with RTV silicone or adhesive-backed tape gasketing.



Thanks. I will look into the thimble. Instead, only because it's cheaper and easier to do, would I be able to stucco the outside of the house all the way up to the pipe (it's a double vent pipe s a smaller pipe in a larger one when I took it apart)? If that's not safe though or wouldn't work I keep the mice out I'll get the thimble part you're talking about. Thanks again.


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