QUESTION

Bolting Table to Tile - I have a ceramic tile floor in my kitchen. I am having a booth built to replace the kitchen table.

The table leg must be securred to the floor with screws or bolts, as the base of the leg will be concealed under the seating part of the bench.

I'll be drilling through the sub floor as well, and the bolts will go down through the floor and sub floor and into the basement. There, nuts will be used to tighten down the bolts to really keep the table leg from moving at all.

Surely, the ceramic tiles are going to crack when I tighten the bolts down. My question is, should I:

(1) put a steel plate over top of the ceramic tile and drill through that, because if the tiles break up the steel plate will still hold everything in place, or:

(2) remove ceramic tiles that would have to be drilled through, and replace them with another material of the same thickness that wouldn't break or crack?

I search for ceramic tile experts and came to your site. If one of the experts has any thoughts on this and can offer any suggestions, I would be extremely grateful.

ANSWER

ANSWER - First, I wonder why it is necessary to attach the table legs that securely to the floor.  I wouldn't expect that it would be subjected to that much stress to require it.

If it is necessary to fasten that way, then I would install the table first then cut the tiles around the legs.  Or if the tile is already there then use a hole saw to cut out a section. where the legs go.  Then use a silicone sealant to caulk around the 1/8" wide gap to allow for movement.

If it isn't necessary to fasten the legs through the floor then you could drill holes through the tile and insert an anchor shield sleeve and screw into it.  Or if you want to leave the tile undamaged, in case the table is removed later, then use a structural (pure) silicone sealant meeting ASTM C920 and bond the legs of the table to the tile floor.  Make sure both surfaces are cleaned properly before applying the silicone.  Silicone bonds tenaciously, allows for some movement, and is relatively easy to remove or repair if necessary. Good Luck.