I got two ginormous quotes back for a roughly 38′ tall masonry fireplace with a fireplace on each of the three above grade floors. So I need a Plan B.
Plan B looks something like using pre-fab fireplaces (like Iso-kern) and metal flues in a wood or steel-framed chase that then is covered on the exterior with full thickness natural stone veneer sitting on a brick ledge. Are there any specific design issues with a stone veneer that tall, besides having the framing designed to be able to handle the side loads (resist toppling over)? I would think the full thickness is better than using adhered stone veneer at that height since all the weight is bearing on the wood framing, as opposed to the full thickness where the gravitational load is all on the foundation (plus masons around my parts seem to prefer full thickness veneer rather than adhered). The advantage of this approach as well is better energy efficiency, since the chase gets insulated and the metal flues are easier to put full-sealing dampers on. From the outside no one would know. Are there any limits to the height of stone veneer like this? Thanks!
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Where are you located?
Mid-atlantic
Ok so no seismic but probably wind shear. The lighter weight of veneer will help. Steel framing is more stable than wood. But bottom line I would talk to a structural engineer to see how they would frame the structure (Hardi over steel frame). 38' is pretty tall and even with horizonal attachment to the house, I think the interior bracing while leaving room for ducts will be a challenge.
differential movement would be a question to answer. don't know if something that high might or might not require control joints.
the assembly ends up being pretty involved [$] with WRB, drainage layer, stucco backing under the MSV.
there are a lot of prescriptive requirements in the code, but first step would be to look at some of the manufacturer website for boilerplate details.