installing a Kitchen Island on tile .

[JerrySats]

I have an island to install on tile floor. I never did this and would like some suggestions on how best to anchor them down.

My thoughts are to use 2x4s anchored to the subfloor with 1/4" lags . I would predrill the tile with a diamond bit so not to break it. The layout won't fall exactly over the grout joints. Thoughts on this ? Thanks Jerry

[rwe2156]

Thats the way I would do it.

[Phil Thien]

Full disclosure:  I have never done it.

But that is pretty much how I've seen it done.

[joe1086]

If your tiles that are drilled also have exposure outside the island, just be sure not to over torque the lag bolts and crack a tile.

[FS7]

I have an island to install on tile floor. I never did this  and would like some suggestions on how best to anchor them down.

My thoughts are to use 2x4s anchored to the subfloor with 1/4" lags . I would predrill the tile with a diamond  bit so not to break it.  The layout won't fall exactly over the grout joints.  Thoughts on this ?  Thanks Jerry

When you drill through the tile, make sure the holes in the tile are oversized. There should be no thread to ceramic contact as that is likely to crack the tile.

Also, be careful not to overtorque. I would probably use EPDM or sill plate gasket material underneath the 2x4, which serves two purposes - it helps to fill the gaps between tiles where the grout is, and it helps distribute the load on the floor. If you have point loads from a high spot in the 2x4, a high spot in the tile (or both together, God forbid) it will be more likely that you crack a tile. It's still not very likely as 2x4s are soft, but it's good to take precautions.

[Bob10]

If you are adding plumbing or electrical in the island where you drill doesn't matter as those additions will trash the floor.  If not I would use wood large enough to allow for the grout lines working

[crokett™]

I guess I'm the only one that would use tape to mark the outline of the island, use a diamond blade in an angle grinder and a helper holding a shop vac to capture dust (or rent a wet grinder) to grind out the outline, then demo the tile that would be under the island. Unless you plan to sell the house before you demo the tile you'll wish you had.

[Bob10]

I thought of that too as it would remove any chance of having a crack that would be darn near impossible to repair without seeing it occur.  Then again anchoring in the grout line would go a long way to reducing chances of that happening

[MKepke]

I like the OP's original approach of using 2x4 cleats - but why couldn't he strategically size and locate the 2x4s so they are screwed into the subfloor through the grout lines? Then screw the island to the cleats.

IME, hardware store lags are crappy steel and a thinner structural screw could be used instead (if needed to stay in the grout line).

I would follow Crokett's recommendation of cutting the tile..but I wouldn't demo it. The cut-line will I) isolate the tile so any cracking won't travel into the visible areas, ii) it will make it much easier to replace the (visible) tile later and iii) lastly leaving the tile under the island means the island isn't sitting in a ~1" deep hole.

Otherwise your (factory) toekick and countertop height are all 1" shorter than normal. Which means you fill in the hole with plywood. Or buy custom cabinets. Or something else equally overly complicated...

-Mark

[Stwood_]

Instead of lags, use concrete screws, and try to position so the screws go into the grout line.
If it's ever pulled up or moved, a simple re grout job will hide the evidence. (unless there is piping and wiring )