Closing up an unused chimney

[forgeblast]

Thinking about moving our woodstove the basement and getting a gas stove for the great room. this would leave a 6'' chimney open. what is the best way to seal it up (not perm) so that i am not getting drafs/air coming down the chimney.

 

[aczlan]

Will it still be used?
Can you access the top easily?

If it will not be used for the time being and you can access the top, I would get some great stuff, a pair of turnbuckles short enough to fit in the chimney and some cardboard. I would use the turnbuckles to "push" out enough that the cardboard can sit on them 4-6" down the chimney and the fill in the hole with great stuff.
When it dries, I would cut the great stuff off level with the top and use some silicone calk to attach a metal cap to the top.

I would then get a blanking insert and put it in the hole where the stovepipe goes.


Aaron Z

 

[MikeyB]

I recently moved a water heater to another part of the house and had the same dilemma. It was a double wall 5" pipe that went through our roof. I really didn't want to remove the pipe and attempt to patch the hole thinking it would probably leak.

With that said, I just removed the cap and stuffed insulation down the pipe from above and did the same from below. I have noticed no air leaks at all. When we get our roof replaced (usually a 3-4 yr. occurrence here in CO due to hail) I will get it patched. But for now it is airtight and I am happy with it, unless my wife talks me into one of those mirrored tube skylights.

Mike

 

[milkman636]

I recently removed a wood stove from our family room. It vented through the side wall to a masonary chimney. I sealed the opening with a can of great stuff and a round backer similar to azclan's suggestion. It woked well. Set the backer at the depth you want and then take your time filling it in evenly.

After a few days I also found it was necessary to hang a nice picture in front of the plugged pipe so my wife would accept the temporary fix.

My chimney is in great shape, it was an inferior stove the previous owner installed that needed to go. When I find a good replacement, I'll be able to scape out the foam, install a little pipe, and start burning in the family room again.

 

[smstonypoint]

Thinking about moving our woodstove the basement and getting a gas stove for the great room. this would leave a 6'' chimney open. what is the best way to seal it up (not perm) so that i am not getting drafs/air coming down the chimney.

You could use a decorative flue cover for the interior opening. Here's a link to one vendor. The price of $16.90 seems outrageous.

6" Decorative Flue Cover

Try checking with "Mom and Pop" hardware stores if you have any nearby. They may have some in stock.

A paint can lid should fit (with some caulking). You could cover it up by hanging a picture over it.

Steve

 

[forgeblast]

Thank you all, yes i want to be able to use it if i need to.
It goes right up through our roof. The stainless pipe on the roof has a cap and screen on it.
I like that flue cover, just have to fine one with out decoration lol, THe paint can lid might work, i have some touch up paint i bet it would match and hold with magnets.
Thank you all, I think i have a plan now.
Insulate and cover. I may put some plastic over the top if i can get up there this summer.

 

[Knotbored]

If the insulation "great stuff" is that foam-in-a-can stuff then remember its a glue also. Put a plastic bag inside the hole first then fill that so the insulation doesn't adhere to the chimney- then fill the bag. It will still be hard to pull out but won't leave a sticky mess.

 

[ace10]

Rigid foam insulation. 2" thickness. Find a busted piece at the Orange or Blue big box. Offer them a couple of bucks for it.

Make a plug out of it either pressing it against the flue to get the size/shape or chalk the opening to do the same. Shape it up using a long utility knife. Bevel it a bit so it fits tightly. Use a long eyebolt and a cuople of big washers through the center so you can easily remove it at a later time.

Bat is not going to hold up to the elements and you'll be up there forever messing with those cans of foam and might break your clay flue (if that's what you've got) when it sets up.

$0.02

 

[Iplayfarmer]

I'm glad to see this thread. I have an old chimney that I vacated this summer. I had a guy offer to fill it with blow in insulation, but I want the option to use it again if I want someday. I may put in a woodstove.

I like the suggestion to bag the top of the chimney and fill it with foam. I'll have to look for a cap now.

 

[forgeblast]

Ace great idea, Knotbored thats why i was shying away from the great stuff, but using it in a bag, is like the inflatable flue closers they have.
ty all, apprecaite it.