I am doing my first large tile job. Hear mixed info re: how to treat the joint at the vertical / horizontal intersection of wall to floor, e.g. in a walk in shower stall. Some say just grout this joint and other say not to grout, use a similar colored caulk. Any suggestions, tricks of the trade? THANKS!
rcj9
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You're likely to hear proponents of both methods - grout and caulk. I lean toward grout since caulk never looks the same and brings it's own issues to the table.
It would be helpful to know more about your situation however.
If this is all new construction with expected shrinkage/movement in the framing likely to occur over the next few years, then caulking in lieu of grout starts to make sense at first blush. However, with the advent of systems like Kerdi et al, the backing for the tile is much more reliable and stable, so grout at the intersection is not a problem. Frankly, for literally thousands of years, grout has been the only solution, but then again, they did not have to deal with our crappy dimensional lumber.
If this is renovation and your structure is already sound, then you might also get away with grout if no modications are made and the tile underlayment is properly installed. (I recently renovated a shower that was poorly installed over green board with only grout and yet still worked fine with no grout cracks for 20 years. Sometimes you get lucky.)
My own preference would be to go with concrete backer board (taped and mudded), a Kerdi (or similar) membrane to stabilize (somewhat) and waterproof, thinset applied tiles, and then use grout at the intersections.
If you haven't already done so, visit the John Bridge tile forum in addition to Breaktime for lots of expert debate on this topic. http://johnbridge.com/vbulletin/index.php
Edited 3/7/2007 11:59 am ET by Thaumaturge
Generically? And with this being your first time tiling?
If the house is wood framed, and the shower walls are lightweight wood frame construction...and you're tiling over cement board, etc...then all changes in plane should be caulked.
If you're floating a true mudwall, then you can grout the intersections.
For caulk, consider a siliconized latex. Better waterproofing due to the silicone, easier to tool due to the latex.
Sanded caulks do a decent job of matching the texture of sanded grout.
You will not use gypsum board, even greenboard, as a tile backer in a wet area. Only if you use Kerdi can you do that, but then you still need to run that past your building inspector before proceeding.
You will not use mastic to adhere the tile to the substrate in a wet area.
Your thinset and your grout will be in powdered form and you'll add water or an admix to them to make them suitable for application. You will not use any type of pre-mixed "thinset" or "grout" that comes already mixed in a re-sealable plastic tub.
Best, Mongo
Oh, one last thing...
Your drainage membrane in the pan? It will sit on TOP of a preslope, so the membrane itself is sloped.
You will not install the membrane on the flat, then do a preslope on top of that.
Be well-drained,
Mongo