Help - Toto unifit install on tile question

[Lvrpl]

I've got a dumb question. I'm installing the unifit adapter for a Vespin II toilet. The instructions list a separate size drill bit depending on whether you're installing the toilet into wood flooring or tile flooring (and it comes with some anchors for tile floors).

I'm installing on porcelain tile that has backerboard and wood subfloor underneath it. Here's my dumb question: do I drill the larger hole and use anchors for a tile floor? Or do I drill the smaller hole for wood subfloor (assuming my screws will go right through the 1/2" or so of tile and actually bite into the wood subfloor).

Thanks!

 

[Reach4]

I would use a drill that will clear the thread of the screw through the tile and then drill into the wood below with a smaller pilot bit. The trick then is to center the pilot drill in the hole. A self- centering drill bit may be useful, or maybe care can keep the small bit sufficiently centered.

With the tile plus backer so thick, you may need longer screws than what is provided.

Drilling porcelain tile is not easy, and it normally needs a special abrasive drill bit. You must keep the business part of that bit wet during the process. If you build a little dam around the hole, don't use Play Doh-- water dissolves it pretty fast.. Putty might be good. I just sprayed water as I drilled, but my tile was only ceramic. Porcelain tile is much more of a challenge.

 

[Sponsor]

 

[Lvrpl]

Great, thanks for the pointers.

Would you say in my application that just using the tile anchors is an inferior option to what you described? I ask because I spoke with Toto tech support this morning and they said they'd just use the tile anchors, even if I've got a wood subfloor below, but I'm sure they just wanted to get me off the phone.

Thanks again.

 

[Reach4]

I expect their recommendation is good. What I don't like as much about that one is that it would need a big enough hole to clear the anchor rather than just clear the screw. I also I am ignorant as to how much pull-upward force it is OK to apply to tile.

An advantage to their method is that it does not require longer screws than what were provided and only needs one drill bit.

Don't forget the clear acrylic caulk around the base. The Vespin base is open at the back, so you can apply the caulk over the part that you can see. That caulk applies the side force to keep the front of the toilet from shifting left and right. Plus it keeps liquids from getting under the toilet. Being less practiced, I used masking tape to keep that limited in spread. A pro would be more skilled and probably not need the tape.

 

[Jadnashua]

The magic key here is, the hole must be large enough to prevent the screw from binding and probably cracking the tile. It's been a long time since I installed mine, but if I remember, the size drill bit they listed for going into tile was too small for the anchors they supplied...I ended up buying some others.

A diamond core bit is easier to make a good hole through porcelain verses a carbide one, which may not do much at all. A good quality porcelain can be as hard a sapphire, which is harder than carbide. To use a diamond core bit, start with the drill at about 45-degree angle, use the edge to gouge a small divot while supporting the edge from walking all over the place, then slowly move the drill up to vertical as you get more and more of a full circle with the cutting edge. Once vertical, just keep going until you're where you need to be in depth. Keep things wet and let the diamonds do the cutting...not too much pressure. You'll see a slurry of fine particles from the diamonds grinding away the tile. You're cutting more like sandpaper than a wood drill bit.