Hello, I have some questions before I finally put 12" slate tile over the top of my new hearth extension and install my Lopi Republic 1250 insert.
I built up the extension with several layers of plywood and more layers of durock and it is now flush with the old brick hearth, which is all covered with a layer of wonderboard. The old brick hearth is not level and the floor was so the new structure had to be built an 1/4" thicker on one side and 1/4" thinner on the other. It feels pretty solid but I still wonder if it might move a little and was going to use flexbond thinset to set the tiles. I used regular thinset between all the durock. Is the flexbond necesssary? Is it as heat resistant as the regular stuff?
Second, there is an ash trap in the middle of the fireplace that is open, one brick wide, and goes to the back of the chimney which is now inside an interior wall now that the house was added onto. The insert will partially cover it. The metal clean out door for the ash trap is right at the floor iniside the wall (I cut it open to look for it), almost completely covered by the new subfloor and inaccesible. If I leave the ash trap open, or just covered loosely with a spare piece of durock, will that be safe for any heat going into the room behind the chimney?
Finally, would I be smart to insulate over the stove, or can the insulation behind the panels around the insert keep the whole thing airtight enough? I am of course installing a new 6" liner and had to open up the smokeshelf to get access to remove the old 8" liner from an old insert, (which had been removed and fireplace had been abandoned by last owner and actually covered with a cabinet I removed) and make room to run in the new one, which I have not done yet. It seems like a lot of open air space to lose heat out now.
Forgive em if these are dumb questions or hard to follow, this site has already helped answer many other questions I've had in planning this project, but I am new to this and have exhausted my internet research capacity and need to finish this thing!
Thanks!
I built up the extension with several layers of plywood and more layers of durock and it is now flush with the old brick hearth, which is all covered with a layer of wonderboard. The old brick hearth is not level and the floor was so the new structure had to be built an 1/4" thicker on one side and 1/4" thinner on the other. It feels pretty solid but I still wonder if it might move a little and was going to use flexbond thinset to set the tiles. I used regular thinset between all the durock. Is the flexbond necesssary? Is it as heat resistant as the regular stuff?
Second, there is an ash trap in the middle of the fireplace that is open, one brick wide, and goes to the back of the chimney which is now inside an interior wall now that the house was added onto. The insert will partially cover it. The metal clean out door for the ash trap is right at the floor iniside the wall (I cut it open to look for it), almost completely covered by the new subfloor and inaccesible. If I leave the ash trap open, or just covered loosely with a spare piece of durock, will that be safe for any heat going into the room behind the chimney?
Finally, would I be smart to insulate over the stove, or can the insulation behind the panels around the insert keep the whole thing airtight enough? I am of course installing a new 6" liner and had to open up the smokeshelf to get access to remove the old 8" liner from an old insert, (which had been removed and fireplace had been abandoned by last owner and actually covered with a cabinet I removed) and make room to run in the new one, which I have not done yet. It seems like a lot of open air space to lose heat out now.
Forgive em if these are dumb questions or hard to follow, this site has already helped answer many other questions I've had in planning this project, but I am new to this and have exhausted my internet research capacity and need to finish this thing!
Thanks!
