Is tuck tape and vapour barrier allowed to touch my chimney thimble?

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Woodstove123

New Member
Dec 10, 2024
6
Ontario, Canada
New house build but reusing my old wood stove. I noticed they tuck taped the vapour barrier around the thimble (I think that's what it's called) in the ceiling. The brand of stove is pacific energy. Is this okay? They are drywalling tomorrow so I'm panicking a bit. If this is not ok, what should be done?

[Hearth.com] Is tuck tape and vapour barrier allowed to touch my chimney thimble?
 
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It doesn't look great. Neither does the rusty ceiling support. The clearance requirement will depend on the brand of chimney support. I don't recognize this one but I wonder how it would maintain 2" clearance from the chimney pipe.

Do you know what brand chimney is on this system? I'm wondering how old thei chimney is. Has it been inspected to make sure it is HT 2000 rated class A, for integrity, and checked to make sure water has not penetrated the insulation?
 
It doesn't look great. Neither does the rusty ceiling support. The clearance requirement will depend on the brand of chimney support. I don't recognize this one but I wonder how it would maintain 2" clearance from the chimney pipe.

Do you know what brand chimney is on this system? Has it been inspected to make sure it is HT 2000 rated class A, for integrity, and checked to make sure water has not penetrated the insulation?
This house is a new build so no water has penetrated the insulation. It's rusted because water did run down the pipe into the thimble in the old house and I'm reusing the stove and parts for the new house.

The wood stove is pacific energy super 27, 6" double wall smoke pipe sysem and 6" ICC Excel chimney system.
 
Hopefully that's good news. Excel is good chimney pipe. My concern with it is that at some point the pipe insulation, which is exposed on the end, might have soaked up water. If it's been inspected and verified dry then it should be ok.

Is this their ERDSI round support with insulation inside the support? If yes, I recall reading that this support is ok to tape to in order to maintain vapor barrier integrity.
 
Hopefully that's good news. Excel is good chimney pipe. My concern with it is that at some point the pipe insulation, which is exposed on the end, might have soaked up water. If it's been inspected and verified dry then it should be ok.

Is this their ERDSI round support with insulation inside the support? If yes, I recall reading that this support is ok to tape to in order to maintain vapor barrier integrity.
I'm so sorry but the info I provided is all I have. The whole system was installed in the old house in 2010 (previous owner) so all I have is a printed email from the wood stove installation company to the previous owner.
In the previous house, rain water somehow got into the thimble part and was dripping onto the woodstove/floor through a hole in the thimble. Where does the insulation end? Is there a visual?
 
Hopefully that's good news. Excel is good chimney pipe. My concern with it is that at some point the pipe insulation, which is exposed on the end, might have soaked up water. If it's been inspected and verified dry then it should be ok.

Is this their ERDSI round support with insulation inside the support? If yes, I recall reading that this support is ok to tape to in order to maintain vapor barrier integrity.
Here is an image of what it looked like fully installed in the old house.
Water was dripping through that hole you can see on the right side.
[Hearth.com] Is tuck tape and vapour barrier allowed to touch my chimney thimble?
 
Is there insulation on the inside of this support? Did the insulation get wet?

Or did someone else remove this chimney support and pipe and reinstall? I ask because the insulation in the support or chimney pipe is still wet, it is not safe.
 
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Is there insulation on the inside of this support? Did it get wet?
I don't know which part you are referring to as 'the support'. I don't know if there is insulation anywhere anyway. We also don't know where the water was coming from, though it was during/after a heavy rain. We only know the rainwater dropped into the house/onto the woodstove through this hole (circled in red). I just realized that there is a cover in this photo over the thimble (original picture in the first post) so the water was within that cover. Water definitely wasn't coming through the chimney itself because we took out the baffle to check when it was actively leaking through that circled hole. Any ideas?

[Hearth.com] Is tuck tape and vapour barrier allowed to touch my chimney thimble?
 
The first picture with the tape attached is the support without the stove pipe connected. The other pictures show the support with the stove pipe attached. The support holds the weight of the chimney above. It should have insulation inside, surrounding the chimney pipe, to be safe with plastic tape on the outside.
 
The first picture with the tape attached is the support without the stove pipe connected. The other pictures show the support with the stove pipe attached. The support holds the weight of the chimney above. It should have insulation inside, surrounding the chimney pipe, to be safe with plastic tape on the outside.
If it does have insulation inside, why doesn't it have a frame around it like the instructions say?
Here’s a note within those installation instructions: 6. You may insulate right up to the support inside the framed opening. Under no circumstances can insulation be permitted to come in contact with the chimney directly (e.g.: above the top of the support). If the insulation depth exceeds the height of the support you must install a support extension (part# RDSE) to keep the insulation away from the chimney.
https://icc-rsf.com/wp-content/uploads/2020/10/XM-ERDSI-ang_2011-02.pdf
 
That is for contact with the chimney pipe. Insulation comes in many types with different combustion temperature ratings. Blown in newspaper and spray foam might have the lowest rating and should never touch the chimney pipe. That is why attic insulation shields are required above the support box when in an attic. They use a specific insulation that is probably ceramic or mineral wool which can handle high temperature.

This is not uncommon for chimney supports where they use their own proprietary insulation in the support to maintain safe clearances while sealing at a vapor barrier. Common, fiberglass insulation is not permitted to touch the chimney pipe.

Is there an attic insulation shield above this reinstalled support box as shown here?

[Hearth.com] Is tuck tape and vapour barrier allowed to touch my chimney thimble?