DIY Home Improvement Forum banner

How to anchor toilet flange to porcelain tile?

85K views 32 replies 17 participants last post by  Peppe1019 
#1 ·
I just had porcelain tile installed on my bathroom floor. I previously extended the PVC toilet pipe so it sticks up well above the floor. I now want to cut it off and cement the flange in place so it rests on top of the tile. I asked the tiler to drill holes in the tile so I can bolt the flange through to the subfloor. He said he never does that, that plumbers just use silicon caulk to "glue" the flange to the floor tile.

Does that sound right? I don't want the toilet moving around and cracking the PVC pipe over time. But I'm also not too excited about drilling through the tile. It is extremely hard. We used the same stuff on the shower walls and it took the shower door installer a loooong time to drill small holes through it with a diamond drill bit, muttering to himself the whole time.

Thanks for your feedback.
 
#31 ·
over the pipe and floor

I'm in the same boat. A contractor had a two man team do a shoddy job of pulling our toilet and replacing a patch of sub-floor and ceramic tile flooring in our bathroom--without noticing that the original, 50+ years old cast iron flange was broken. The toilet leaked the day after they left, and they were not willing rectify the situation without additional cost.

We're going with a different plumber, who has been tolerant of our questions at every step of the way. Plumbing treatises, not contractor treatises, that I have read cite, "The pipe coming through the floor should be of sufficient length above the floor to be flanged over." (Standard Practical Plumbing, 1910)

The videos that I have watched about installation of old school lead caulked joints remove lead and oakum from between the soil pipe and the flange that sits over the soil pipe and tiled floor. Plumbers in those videos installed new oakum, poured new molten lead, and caulked the new joint such that the cast iron flange rested over the soil pipe and over the tiled floor too.

I suspect this laying the flange flush with the floor has to do with the introduction of plastic flanges prone to breakage in recent decades. I agree that if you bolt a flange to the subfloor and it fails, you may not see the damage until your joists are shot, because leakage cannot occur on the tile. Such a leak seeks an outlet below surface floor level to occur on tile backing or subfloor. What is worse is that such a leak may not be seen until the joists are damaged. Joist replacement is a far more expensive contractor call than enduring a plumber's grimaces and insisting on having the flange mounted over a soil pipe and tile.

Since we cannot find someone willing to pour a new, reliable, lead caulked joint--heat compression welding that does not necessitate bolting the flange to the floor--we are going with a cast iron twist and set flange. I do confess worry about the small diameter of the flange end that inserts into the soil pipe. Yet, the toilet's curved ceramic trapway diameter is smaller. So, it will probably work.

We took our twist and set replacement flange to the hardware store for outfitting with appropriate stainless steel toilet bolts, floor bolts, and to buy a bit that matches the latter's diamond bit size. For precise floor bolt length, we realize the floor bolts will have to go through the tile, grout, adhesive, cement board, and partially through the subfloor.

When we asked, our plumber said he will bolt the flange down atop the tile for us. (I am learning to ask politely and look past grimaces to avoid making my own in paying to redo a bad job.)

For our 125+ years old house, there is an added plaster of paris set for leveling the commode issue. Though the floor is not level, the commode must be. We also recently had our line snaked out to the sewer with imaging, because you can blow out your wax ring by plunging a clogged line. When this is done, we will limit the toilet for specific business only--no standing on it to change the 11 foot high light fixture, because that can blow out the wax ring too--given our uneven floor.
 
#33 ·
Im a veteran plumber have done endless commercial and residential rough ins and the flange is always secured to the subfloor and should be flush with finished floor..whatever the sources are that say on top are totally incorrect and any REAL liscensed or journeyman oplumber will tell you that..
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top