Stone cladding fasteners through 2″ of XPS foam?
GBA Editor
| Posted in Green Building Techniques on
Anyone have any techniques for fastening of stone claddings through thick insulated foam sheathings (2″ and greater)? Would like to keep the thermal bridging of these fasteners to a minimum.
FYI: Exterior walls framed both at 16 and 24″ OC, and fully sheathed with structural OSB or Plywood. Also building in an area with heavy seismic and wind loads.
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Replies
What's the thickness of the stone - is it thin veneer or coursed masonry?
It's a natural stone thin veneer.
I'd be looking at sections of z-bar set vertically as standoffs, back flange screwed through the sheathing to the studs, front flange carrying the mortar backer,. The Z-bar probably wouldn't need to be continuous but I'd want an engineer's signoff for gauge, o/c, dimension and fasteners. You don't want to take chances with offset loads with such a crack-sensitive finish material, especially with the external conditions you mention. I'd trade a little thermal bridge for proper structural integrity.