Clearance to drywall from wall thimble

[moey]

My picture will do a better job explaining then me. I'm hanging insulation 2 inch foam covered with drywall how close can I get to the wall thimble with the insulation and drywall? What about the cleanout which is a little bit below the thimble? The thimble is a single wall metal pipe that goes into a clay chimney. The stove hookups are not used but I would rather not make them unsafe. Thanks for the help.

 

[Chinneysweep187]

Masonry thimbles and single wall stainless pipe require 18" clearance. I would substitute for a durock concrete wall board or attach wire lathe to the wall parge a skim coat and apply lick and stick stone .

 

[moey]

Masonry thimbles and single wall stainless pipe require 18" clearance. I would substitute for a durock concrete wall board or attach wire lathe to the wall parge a skim coat and apply lick and stick stone .

It does not need to look finished. If I put up the Durock ontop of the insulation can the 18 clearance be reduced? Or is it still bound to the 18 clearance no matter what I put on top of it.

Sounds like Im stuck having the insulation no closer then 18" all the way around.

 

[Chinneysweep187]

18" clearance meaning to anything combustible. Durock isn't combustible . If the insulation has a high heat rating which I wouldn't go less than 1000 degrees you can put it as close as you'd like

 

[begreen]

You may find this article helpful.
https://www.hearth.com/econtent/index.php/articles/passing_a_chimney

 

[skinanbones]

As an inspector, if i know that you had 2" foam board with dry wall covering it. I would want to see something simular to the ICC insulated wall thimble in place, so that i know for sure the clearances are met. Here's a link to the product (broken link removed to http://www.icc-rsf.com/main.php?t=chem_produits&i=46&d=&l=en)

 

[moey]

I think Im just going to have the foamboard stop 18 inches away and call it good. Having a section of basement wall 5 ft by 7ft uninsulated is not the end of the world. A portion of that wall on the otherside is crawlspace so its not even a full outside wall so its more like 5 ft x 3 ft uninsulated. If my plans changed in the future I can change it. Right now changing the thimble on an unused flu to accommodate insulation just seems silly.

Thanks for the info all!!

 

[Chinneysweep187]

I think Im just going to have the foamboard stop 18 inches away and call it good. Having a section of basement wall 5 ft by 7ft uninsulated is not the end of the world. A portion of that wall on the otherside is crawlspace so its not even a full outside wall so its more like 5 ft x 3 ft uninsulated. If my plans changed in the future I can change it. Right now changing the thimble on an unused flu to accommodate insulation just seems silly.

Thanks for the info all!!

I wouldn't change the thimble it makes no sense in my opinion . Your thimble is in a cement wall clearances are fine . Like in the article begreen posted you can run cement board "durock" right up to the thimble