I'm in need of some advice on a material for a non combustible wall - specifically, a cement type panel that can take heavy stones without failing and is resistant to higher temperatures. What makes this build more complex is that:
1) require minimum 7/8 inch air space between combustible wall and non combustible wall which also requires min 1 to 3 inch air space at bottom and top for air flow. Thus the wall will be a floating wall. (I already determined that 7/8 furring channels at 18 gauge with minimum G60 hot dip galvanization must be used as per Durock. Durock says 20 guage but 20 guage doesn't give the G60 galvanization, so I must use 18 gauge).
2) wall has halved stones glued on using flexbond. Wall weighs 1500 lbs and is floating due to air space requirements at the bottom.
3) planned on using durock cement board where durock states its product is good to hold 15lbs per square foot, but I'm at 26 lbs per square foot, over the safe rating.
4) durock is rated for up to 190 deg F before it starts to degrade. This wall is about 8 inches from the back of my fireplace and may reach a higher temp. I'm worried that the higher weight and temperature may cause a failure of the attached stone.
5) my fireplace installer said there should be no furring channels directly behind the fireplace (about 2 feet), but durock states a span of two feet reduces the carrying load of durock further, which increases a risk of failure due to weight.
I need help with sourcing a superior cement board, that can take greater loads and temperature, than Durock. Please let me know of any such products.
1) require minimum 7/8 inch air space between combustible wall and non combustible wall which also requires min 1 to 3 inch air space at bottom and top for air flow. Thus the wall will be a floating wall. (I already determined that 7/8 furring channels at 18 gauge with minimum G60 hot dip galvanization must be used as per Durock. Durock says 20 guage but 20 guage doesn't give the G60 galvanization, so I must use 18 gauge).
2) wall has halved stones glued on using flexbond. Wall weighs 1500 lbs and is floating due to air space requirements at the bottom.
3) planned on using durock cement board where durock states its product is good to hold 15lbs per square foot, but I'm at 26 lbs per square foot, over the safe rating.
4) durock is rated for up to 190 deg F before it starts to degrade. This wall is about 8 inches from the back of my fireplace and may reach a higher temp. I'm worried that the higher weight and temperature may cause a failure of the attached stone.
5) my fireplace installer said there should be no furring channels directly behind the fireplace (about 2 feet), but durock states a span of two feet reduces the carrying load of durock further, which increases a risk of failure due to weight.
I need help with sourcing a superior cement board, that can take greater loads and temperature, than Durock. Please let me know of any such products.
