Suggestions to attach live edge bar top to stone corbels?

[Sean Leonard]

I have a red cedar live edge bar top that needs to be attached to a split-level bar top. The counter is easy enough, but I'm struggling with the best way to attach the bar top to the corbels.

My original plan was to drill through the wood and into the stone with concrete anchors, countersink them, and inlay over the top to hide the hardware. But that would require me to do the finishing on-site, which I would rather not.

Plan B is drill pilot holes through the top of the corbels with a long masonry bit and hammer drill, countersink the holes at the bottom of the corbel with a diamond countersink bit to conceal the hardware as much as possible, and then use the anchors to secure the bar top from the bottom.

At this point I'm think plan B is the best option since I can finish the tops before bringing them for the install. I wanted to get some feedback from others on the options, or see if there is another better way of installing these.

Sean

432991

432992

[Erik Loza]

I like Plan-B but what if the homeowner does something like sit or stand on the slab after install? Would there be a risk of it tipping over or levering up if it's not through-fastened or screwed from below?

Erik

[Kevin Jenness]

How about concealed hanger bolts screwed into the underside of the cedar and potted with epoxy into the stone? Not reversible, but invisible.

[Osvaldo Cristo]

I never tried before, but, does construction adhesive work there? I was thinking on the stuff that looks cauk compost...

[Sean Leonard]

I like Plan-B but what if the homeowner does something like sit or stand on the slab after install? Would there be a risk of it tipping over or levering up if it's not through-fastened or screwed from below?

Erik

With plan B it wouldn't be through-fastened, but it would be screwed from below. This seems like an acceptable option for normal use, but not for any "coyote-ugly" action. I also worry whether the stone is brittle and if drilling with a hammer drill will break up the stone at all.


How about concealed hanger bolts screwed into the underside of the cedar and potted with epoxy into the stone? Not reversible, but invisible.

That's a good idea. Like you said, it would be permanent so if the homeowner ever wanted to remove to replace or restore the top it would be hard without damaging the stone. I wish the GC who did the stone would have installed some brackets in the wall to all me to mount the wood--that would have been best. After all, he knew what the customer wanted.

[Jamie Buxton]

How 'bout this.. You screw a metal plate down to the top of each corbel. It is perhaps 1/8" thick, and extends an inch or so beyond the sides of the corbel. Wood screws go up through that inch into the underside of the wood. There's no visible connector on the top of the wood. The screws which go down into the corbel can be smaller diameter and much shorter than your Plan B, so they're less likely to damage the stone. They're Tapcons or the like.

This approach lets you undo the wood screws to remove the plank for refinishing a few years down the road.

[Jamie Buxton]

If you don't even want to see the edges of the plates, inset them up into the plank. They're only an eighth thick, so that little recess has little effect on the structural integrity of the wood.

[Jamie Buxton]

Around here, the building codes say that wood which touches concrete which touches dirt must be pressure-treated, to keep termites and other pests away. If the plate I suggested is a little taller, it can serve as an air gap to kinda observe the code.

[Jim Becker]

Drill holes in the top of the corbels, insert beefy threaded hanger bolts into the bottom of the slab so they can insert into the holes. use appropriate adhesive on the tops of the corbels and mortar in the drilled holes. It's not going anywhere at that point, IMHO.

[Doug Garson]

If you want the slab to be removable, how about epoxy the steel plate (which overhangs the stone) to the stone, put threaded inserts in the slab and screw the slab down to the plate. It appears your slab is quite thin (3/4" ?), thus the inserts. If the slab was thicker, say 1 1/2" I would be comfortable with screws.

[Jim Becker]

Doug's solution is worthy for removable for sure. The metal plates could theoretically be made flush with the stone by grinding out a channel for metal.

[Bill Dufour]

If you want the slab to be removable, how about epoxy the steel plate (which overhangs the stone) to the stone, put threaded inserts in the slab and screw the slab down to the plate. It appears your slab is quite thin (3/4" ?), thus the inserts. If the slab was thicker, say 1 1/2" I would be comfortable with screws.


If this is outside look at galvanized FAP plates from Simpson. Maybe cut in half. Or a piece of stainless steel. Regardless be mindfull of galvanic corrosion.
Bill D.
PS: The FAP plates may be available in stainless. Much of the Simpson catalog can be ordered in stainless.

[Doug Garson]

One more thought, oversize the holes in the plates to allow for wood expansion/contraction. Maybe add a rubber washer so you can snug it up and still allow for movement.

[Bruce Wrenn]

Because the top of the stone isn't flat, that's your first problem. You need to level it up before attaching anything. If it were mine, I would wrap top on plastic, then using floor patch compound, place a bed along the top of the stones, similar to laying brick.. Then quickly rest top on bed joint compound, checking for level as much as possible. After bedding compound has set up, remove top, and then attach steel plates to stone work, before attaching to bottom of slab. As mentioned above, slotted holes would have to be used at slab attachment.

[Sean Leonard]

If you want the slab to be removable, how about epoxy the steel plate (which overhangs the stone) to the stone, put threaded inserts in the slab and screw the slab down to the plate. It appears your slab is quite thin (3/4" ?), thus the inserts. If the slab was thicker, say 1 1/2" I would be comfortable with screws.

This sounds like a good option, although I've never epoxied steel to stone. Is there a special epoxy recommended for that? The slab is just shy of 2 inches thick so screws would be fine.

[Sean Leonard]

One more thought, oversize the holes in the plates to allow for wood expansion/contraction. Maybe add a rubber washer so you can snug it up and still allow for movement.

Is there an epoxy that can adhere the FAP plates to the stone? So I don't need to route out a channel for the anchor heads in the underside of the bar top?

[Doug Garson]

I think there are epoxies or other adhesives specifically for attaching steel to stone, I haven't done it myself but I would guess if you talked to a place that sells stone they could advise or talk to a place that sells epoxy and adhesives.