Considering that this if for inside application the very first thing i might state is always to stick to the manufacture's directions. With respect to the stone weight you will have various install methods.
However... provided no information from producer:
- I would personally perhaps not cement board over drywall. You would need to use longer screw needless to say however the proven fact that the screw is not binding for the very first half-inch will place some really serious stress about this link. If you're dead set on carrying it out, glue it then screw it.
- I would personally have have really set up on drywall in dried out places. Provided this isn't a bath I do not see a performance difference between the drywall or concrete board unless the stone was acutely hefty
- To prep for drywall install I would double up on the drywall screws, install wire mesh throughout the area, then provide a little scrape coating across mesh.
Whenever you can provide myself specs on rock I'm able to have more particular or transform my solution but nothing wrong with drywall provided the area isn't wet (and trained with isn't on a hearth however you mustn't have drywall there currently.)
Sheet of drywall is 48x96" or 4608 sq/in. The stones tend to be each 108 sq/in. Meaning you'll need 43 stones per sheet. The OP states the stones are 6.25 weight, meaning the wall surface would-be encouraging about 260 lbs/sheet.
Each drywall screw holds about 90 pounds of shear force without tearing drywall. A typical sheet of drywall has actually 30-40 screws. Let's imagine 30 to offer minimalist figures. That means your sheet of drywall can probably hold 2700 pounds which is 10 times your stone body weight.
My focus is on reinforcing drywall and offering a beneficial substrate - cable mesh. Including tangible board if you ask me just weakens the text into framing - basically you are saying that drywall can not deal with the stone however it can handle the backerboard and rock. If you prefer concrete board then it should always be on wall - i might not make use of plywood because does not bond to thinset as good as drywall or backer.
From a practical perspective... We have put in rock lots of times on drywall. Your concerns about the wall dropping over tend to be ludicrous. The extra weight is not becoming taken out. The weight goes along. 90per cent of installation problems will likely to be utilizing the thinset and its own bond. You may be targeting a thing that has actually small bearing in your finished product.