Best Firebox insulating question

[rick clifford]

My installer came to install my wood insert and turns out the clay tiles will have to be removed so he has to come back. Now that everything is open and I have a couple days I want to insulate the walls of the firebox of my exterior wall chimney. It appears that roxal and durock are the preferred method (plus a block off plate) and just want to confirm this or hear other thoughts. Other question is this roxal and durock the standard stuff on the shelf at the big box stores. Or is there special non combustible stuff somewhere else. Also the entire roof of the firebox is cast iron so how can I secure the block off plate, (Its what remains after damper door was removed) I take this as a blessing to have the time to insulate and weather isn't too cold in Jersey right now. Thanks for any advice

 

[rwhite]

Roxul comfort batt if you can find it. Other wise the safe and sound is the same stuff just a bit denser and a little less r-value. Both have a fire rating of 2000 some degrees. If you have a lip on the damper you can cut the sheet metal and just let it rest on the damper with roxul on top or Bend it and screw into the brick.

I may be cautious about getting all that in there prior to busting out tiles. I've never done it but I imagine it makes a mess and will be in the way.

 

[rick clifford]

Roxul comfort batt if you can find it. Other wise the safe and sound is the same stuff just a bit denser and a little less r-value. Both have a fire rating of 2000 some degrees. If you have a lip on the damper you can cut the sheet metal and just let it rest on the damper with roxul on top or Bend it and screw into the brick.

I may be cautious about getting all that in there prior to busting out tiles. I've never done it but I imagine it makes a mess and will be in the way.

Thanks and your right as I want to fabricate everything and have it ready to go after we break out the tiles, drop the liner and secure all in place. I will look for a lip or two. Is there a high temperature sealant I can use in a caulking gun? What is the name and where can I find some in New Jersey?

 

[rwhite]

Thanks and your right as I want to fabricate everything and have it ready to go after we break out the tiles, drop the liner and secure all in place. I will look for a lip or two. Is there a high temperature sealant I can use in a caulking gun? What is the name and where can I find some in New Jersey?

Any pics of the damper area.

 

[MurphyMacmanus]

Just finished a similar project this week. Refinished Quad 5100i, exterior 13x13 masonry chimney, insulated 25ft liner, Roxul insulated firebox covered with sheet metal and block off plate. Ended up cutting out the damper and the top two middle fire bricks to fit the liner through.

 

[rick clifford]

Just finished a similar project this week. Refinished Quad 5100i, exterior 13x13 masonry chimney, insulated 25ft liner, Roxul insulated firebox covered with sheet metal and block off plate. Ended up cutting out the damper and the top two middle fire bricks to fit the liner through.

Just finished a similar project this week. Refinished Quad 5100i, exterior 13x13 masonry chimney, insulated 25ft liner, Roxul insulated firebox covered with sheet metal and block off plate. Ended up cutting out the damper and the top two middle fire bricks to fit the liner through.

Real nice and the sheet metal would work best for me in the rear due to limited space. Doesn't the roxal get compressed when you secure the sheet metal and is that ok to do? What did you use to secure it to the walls. What type of screws? I tried to post photos from my tablet and I don't think it worked. Oh well. I will try it from this computer and thanks. Those are towels stuffed up there temporarily. The damper door is removed and the back of the damper frame snapped off cleanly at the hinges so its the smoke shelf in the rear and the cast damper frame and lintel in the front. I am sure you know that. Thanks

 

[MurphyMacmanus]

Real nice and the sheet metal would work best for me in the rear due to limited space. Doesn't the roxal get compressed when you secure the sheet metal and is that ok to do? What did you use to secure it to the walls. What type of screws?

Tapcons which are screws designed to bite into masonry. You run them in deep enough to snug the sheet metal to the insulation but not deep enough to totally compress it.