insulating and leaking

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beermann

Feeling the Heat
Jan 16, 2017
318
canada
Late last year I insulated around the flue of my chimney. I'll be putting a blocker plate on later this winter. My first question is should I climb on my roof and place some insulation at the top of the flue and may even cram whatever insulation I have left down there between the chimney and the flue.

Second question is this:
I have some liquid dried around the top of my fireplace. Should I be concerned and should I perhaps put some sealant were the flue meets the fireplace.

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That looks to be sealed up pretty well, not sure how much a block off plate will increase efficiency?
You most likely need some work done to the chimney crown. Sometimes it just needs sealed rather than replaced. Hopefully it’s repairable. Can you get a picture of the top of your chimney by chance?
 
That looks to be sealed up pretty well, not sure how much a block off plate will increase efficiency?
You most likely need some work done to the chimney crown. Sometimes it just needs sealed rather than replaced. Hopefully it’s repairable. Can you get a picture of the top of your chimney by chance?


I can get a picture tomorrow.

I know that the plate on top of the chimney does not have sealant around it. Maby this is my issue.

It's still in great condition as it's only 2yrs old.
 
I can get a picture tomorrow.

I know that the plate on top of the chimney does not have sealant around it. Maby this is my issue.

It's still in great condition as it's only 2yrs old.
The top plate should have a generous bead of silicone underneath it. Is there a storm collar? Pics will help.
 
The top plate should have a generous bead of silicone underneath it. Is there a storm collar? Pics will help.

What about the extra insulation I have left over. Should I cram as much as i can along the side of the flue from up top as well?
 
It won't hurt. The upper 2-3 ft is often where most buildup occurs.
 
I insulated a couple feet around the top of the flue and used high temp caulking as a sealant around the cap. I also saw some cracks in the clay and sealed it up with the caulking. A small repair job to replace that clay liner next summer I think. From what I could see the other clay liners were fine
 

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I insulated a couple feet around the top of the flue and used high temp caulking as a sealant around the cap. I also saw some cracks in the clay and sealed it up with the caulking. A small repair job to replace that clay liner next summer I think. From what I could see the other clay liners were fine
There’s no reason to replace any clay liners if you’ve got an insulated stainless liner. You don’t need to use red high temp silicone either. Regular silicone is high temp enough.
 
There’s no reason to replace any clay liners if you’ve got an insulated stainless liner. You don’t need to use red high temp silicone either. Regular silicone is high temp enough.


The liner is not fully insulated except for the 2 feet of insulation I put in at the top and the insulation around the damper above the stove.

If you reckon that's enough I'll stop there and work on insulating around my insert and getting some flashing to cover things up around the insulation.

And yeah I thought the red silicon I got might be overkill but I wasn't sure. Thanks for letting me know.
 
You need a new crown on that chimney.
 
The liner is not fully insulated except for the 2 feet of insulation I put in at the top and the insulation around the damper above the stove.

If you reckon that's enough I'll stop there and work on insulating around my insert and getting some flashing to cover things up around the insulation.

And yeah I thought the red silicon I got might be overkill but I wasn't sure. Thanks for letting me know.
Insulated liners always perform better, and it’s a must if you’ve got cracked clay liners.
 
Insulated liners always perform better, and it’s a must if you’ve got cracked clay liners.
What does cracked clay have to do with insulation on a liner???? I agree the liner should be insulated for sure. But not because of cracked tiles
 
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In short I cant fit an insulated liner down the chimney. But I can squeeze a bunch of insulation around it from the top and bottom.

I was happy with its performance prior to insulting and sealing the top. I'm looking forward to seeing how it performs with insulation around the insert as well.

Thanks everyone