Ask The Experts, Sept 2011

QUESTION:
I am a consumer in Oregon currently going through a complete bathroom remodel. We are currently at a standstill with our contractor due to tiling issues; I am hoping someone can help me to make sure I understand code and tiling processes correctly.

We are using a general contractor. The entire bathroom was gutted, new plumbing, electrical and total new tile on floors and walls; everything new. We have a contract and he is to do all the tiling.

My understanding is that the tile should be completed, meaning: all tile, grouting, cleaning of grout and sealant should be finished before anything is installed in the bathroom. The contractor has not finished grouting where the walls and floors meet and has not done any cleaning and sealing of tiles. But he has gone ahead and installed the vanity as well as toilet and shower fixtures. We are concerned that since he has installed these items without finishing the grout and sealing of the grout, any water that gets behind the shower fixtures and the vanity can cause damage.

We believe he needs to take out the vanity and the plumbing/shower fixtures that have grout running behind and under them for the tile to be completely sealed. He says he is not going to do it. If he had finished all tiling work before installing these items we’d have no problem.

ANSWER:
I am hoping this note can help ease your mind. Yes, grouting and cleaning any grout residue from the tile surfaces should be completed before installing fixtures. Where the wall tile meets the floor tile, or where tile meets a tub, should NOT be grouted. This area needs to be filled with a flexible sealant (like silicone caulk) to allow for the slight but certain move- ment that will be occurring at those changes in plane.

Sealers are typically misunderstood by consumers. You understand correctly that tile and grout are not waterproof. But the waterproof- ing (or moisture barrier) is actually designed into the substrate, or the system used BENEATH the tilework. Even if the system were not tiled, the waterproofing would not allow water to damage your structure. The best sealers are the ones that allow moisture or vapor transmission, or breathability. Sealers are not (and should not) be a waterproofing or moisture barrier. Sealers are NOT required in any tile installation, and at best should be looked at as an add- on product that allows the migration of smaller water molecules, but stops the larger dirt and oil molecules from getting a firm grip onto the surface, allowing greater ease of cleaning. Therefore, sealing is good if using a quality sealer, but not required.
To your question about the toilet and vanity being installed before the sealer, I hope the previous explanation lets you understand that since the areas beneath these permanent fixtures are protected, and never will need cleaning, there is not really any need to seal the tile and grout where they reside.

Michael K. Whistler
NTCA Workshop Presenter/Technical Consultant