Up above the roof, we want a massive-looking stone-faced chimney, but there is no masonry fireplace below. Just a Heatilator-type fireplace with a doublewall SS stack tube.
We are thinking of a wood-framed OSB-sheathed chimney box, supported with appropriate wood framing down through to thickened reinforced pads in the basement floor, and large steel angles bolted to the chimney box, to function as stone shelves on all four sides.
Sound OK for 4″ of stone veneer, maximum of 8′ height?
And how about real granite slabs for the slab-post-and-cap assembly on the top? If MDF kitchen cab carcases can support granite and concrete countertop work, it is just a question of the properly-sized wood columns and beams, right?
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We've done several, however, in 3/4" plywood. I'm not so sure about OSB.
Conventional framing, plywood sheeted, applied stone, but used dryvit for the massive "limestone" cap. Even used decorative clay chimney pots on a few.
Here is where we are going. What do you think was used here? I know there is no real stone and block structure under that chimney.
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Yes, it looks great. As I said, I'm not a fan of OBS. My caution comes from the possibility of a cracked joint or stone and OBS's resistance to water infiltration until the flaw is found, maybe months later
As far as the faux or shaved real stone veneer. This is exactly the type of application we've had experience and success with. You have the added advantage in this application of not having a flat cap with the flues penetrating. I assume that's where you intend to use the slabs. Be sure you have weight transfer to something structural below.
Be sure to pay attention to the flashing detail at the stack base/roof connection. Be sure to use an experienced applicator, in our case it's our dryvit contractor, and follow the manufacturers instructions.
I see you have and existing stone. The faux stone is somewhat lighter in weight, usually with matching patterns and color to the natural, but in any case you are separated far enough to avoid a direct match comparison.
Never serious, but always right.
Let me rephrase my question. And let's get the OSB issue off the table. I'll use CDX or even marine plywood if it is an issue.
To do a bang-up job on a reproduction of this house, we will want to use real stone veneer on all the lower house wainscot and terrace wall facing. The kind about 4" thick, laid on a stone ledge or shelf.
To have the chimney box finish look the same as that on the elements of the lower house walls, we will want to use the same stone, laid stacked against, not stuck on flat, the chimney.
My question is, have you have success doing some kind of a structural masonry-supporting ledge, say, a heavy-wall steel angle, bolted to a wood-framed chimney structure, on which you could lay 4" thick veneer stone, to achieve a real-stone-look chimney?
I know about and have seen the faux stone, aka cultured stone, veneer products, and I know they are light enough (cast using lightweight aggregates) and thin enough (1 to 1-3/4-inch thickness) so they don't need a stone shelf support, but I am not sure I can get a product like this to be a dead-on match to the real stone I want to use below, on the house walls.
I want to use real stone as a veneer on the above-roof chimney, and need to know if this is possible, and if so, how it is done.
We've only done a couple the way you're suggesting. However, the chimney height was less, one about 4', the other 6' and we used 2x6 studs. The angel iron was, if I remember right either 17 or 23 lbs per ft, 4". Just ask the steel supplier for the same weight that you would use on a 8' wall veneer when there's no brick ledge. Again make sure you've transferred the weight to the foundation a basement pad, or etc. Also as I mentioned the chimney/roof flashing detail needs to be well designed.
However, Bob, I'd lay some sample faux up, take a look from the ground and see how it looks. It seems far enough away from both where you're looking at it and from the other stone, to not be noticeable. But full stone would be the ultimate.
Good luck, send pictures.
Never serious, but always right.