Hearth Design

[woodjdieter]

As part of the basement remodel, the entire basement floor was covered with foam board and the joints spray foamed and sealed with Tyvek tape, then topped with 3/4" plywood screwed to the concrete so the hearth is being built on top of this. The basement walls are being spray foam insulated 2" deep. The back wall area behind the stove is not being foamed and that's the reason for the rigid insulation which is also sealed to continue the integrity of the 2" wall foam. Beyond the insulation value, creating a sealed thermal break will keep the basement relative humidity manageable in the warm months, and the stove won't have to warm all the concrete floor and walls in the heating season. The noncombustible area around the stove and stove pipe exceeds all the manufacturers requirements, and all the combustible material used to build the back wall and hearth will be covered in slate and stone. At this point I'm going to extend the 8" SS sleeve beyond the new back wall keeping all combustibles 6" away radially. I'll leave it to the installers to go from there when they come back to drop the liner in the chimney and re-install the stove on the new raised hearth

 

[bholler]

it should be 18" from that 8" ss crock i agree about using a section of class a or better yet a wall pass thru thimble in that case you could reduce to 2" with the class a or what ever the pass thru manufacturer specs for it

 

[woodjdieter]

bholler, I asked the installer (who also is an employee of the Stove and Fireplace store where I bought the stove) that did the original installation sans flu liner do to the slick roof conditions, how the flu liner would connect to the dbl. wall stove pipe had he been able to install it. I thought he said the liner will go all the way through the 8" ss sleeve. Sounds like that is not acceptable either. Is there any way to re-install the stove and the new flu liner using the existing 8" ss sleeve correctly?

 

[bholler]

Yeah the tee snout from the liner can be brought all the way through that 8" crock and then hook up your pipe the space between the 2 will then be packed with insulation. This is the normal way that it would be installed and i am assuming how he would do it. The only problem is that this way will not reduce your clearances you will need 18" from that crock unless you use one of the other suggestions mentioned previously. But if he installed it last time by sliding double wall into the crock i would not trust his judgment because that is just plain wrong.

 

[woodjdieter]

Ok, I'll maintain 18" of clearance and make sure he installs the liner as you've described. What type of insulation is typically used. When he ran the double wall into the flu he used what looked like door gasket rope thick enough to fill the void and wrapped it around the double walled pipe 3 times.