I’m doing a tile shower with cement backer board for the walls and a mortar shower pan/floor. Do the joints where the wall meets the floor need to be caulked or grouted?
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Caulk. Be sure to leave a small gap for the caulk to go into.
Are you impersonating me? :)
I caulk before grouting. Let it cure good.
I just grout it. Probably the better way is to use a sanded caulk, but I just grout it.
Because I can.......Regards,
Boris
"Sir, I may be drunk, but you're crazy, and I'll be sober tomorrow" -- WC Fields, "Its a Gift" 1934
I second the motion to caulk first then grout. I use the caulk color matched to the grout from the grout manufacturer.
Most of my work involves shower ROOMS with gang showers, so it may be different for smaller single stall units. We always specify a sealant joint around the perimeter of the tile floor. This joint occurs at the joint between the floor tile and the coved wall base tile.
The Tile Council of America has a wealth of details for tile installation.
caulk backer board install tile then caulk tile I use solar seal 900 its for exterior use comes in siding colors its tuff, sticky, flexible 800% elongation, and cleans up with mineral spirits you can even mix colors for custom work put in a big cow syringe and apply.
matching grout caulk.
and run the membrane up the walls about 6 inches and ya don't have to worry about double back caulking ... the cbu shouldn't be touching the floor anyways ... run the membrane ... the wire mesh ... and the mud bed up the wall 6 inches.
Jeff
Buck Construction Pittsburgh,PA
Fine Carpentery.....While U Waite