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How to insulate a concrete block chimney

11K views 5 replies 4 participants last post by  21boat 
#1 ·
I have a concrete block chimney which passes between a bedroom wall and the garage. I have insulated the wall except where the chimney is, but the wall still seems cold. I want to insulate the chimney which doesn't get very hot, and want to make sure I do it safely and to code. I live in Maryland. Thanks for any suggestions!
 
#3 ·
In my neck of the woods we use Rock Wool insulation for fireproofing. Its also required between a chimney when the chinnmey is inside a home penetrates another floor where the box framing around that chimney is a fire chase IE Rock Wool stuffed against the chimney and wood framing stops a fire chase.

http://guide.rockwool.co.uk/products/building-insulation/fire-barrier-systems.aspx

It also is directly applied to the Chimney with no airspace

Should pass code in your area double check

Rock wool does pass the NFPA code ( National Fire Protection Agency..)
 
#4 ·
In my neck of the woods we use Rock Wool insulation for fireproofing. Its also required between a chimney when the chinnmey is inside a home penetrates another floor where the box framing around that chimney is a fire chase IE Rock Wool stuffed against the chimney and wood framing stops a fire chase.

http://guide.rockwool.co.uk/products/building-insulation/fire-barrier-systems.aspx

It also is directly applied to the Chimney with no airspace

Should pass code in your area double check

Rock wool does pass the NFPA code ( National Fire Protection Agency..)
this is true, I use it to seal the air leakage at the top plate all the time, but the unit may call for a 2" air space. This area is needed by design and should not be filled with insulation.
 
#5 ·
#6 ·
My posted web site is a NON-combustible material that means the 1” or 2’ to a ‘Combustible is not an issue any more. I am a mason and let me say Chimney block is NOT a “Unit” and those Chimney block can also have insulation in them and are manufactured as such. Also the Rock Wool I suggested is used for a FIRE barrier and we used a ton of that in a Hospital I worked on for soundproofing and Fire stopping. It’s a NON-combustible.

To have an air space is a trade off . For fire to exist you need 3 things Heat, Fuel. Oxygen, A 1” or 2” can also become a fire chase. But the powers to be decided that trade off was acceptable. BUT. Cant transfer fire through a NON Combustible..

Many times I deal with Fire chases. Example a PVC pipe going through a floor in a multi dwelling is considered a fire chase. Metal/iron pipe has to be used along with fire proof caulking around that penetration..
 
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