joint between backer board & green board
johnnyd
| Posted in Construction Techniques on
First time tiling a bathtub surround, have figured out (with help from this forum) how to get tub and backer board installed, fastened and oriented (not done yet, though), and this question is specifically about the joint between the backer board and the sheetrock, where the transition from tiled surface to painted surface takes place.
Do you tile OVER that taped joint or just up to it?
Do you always use greenrock for the untiled portions of the bathroom?
Answers will help my figure out if and where I might need to add additional blocking.
Replies
Do you tile OVER that taped joint or just up to it?
Yes.
(BTW, you did use the fiberglass tape, didn't you?)
Actually, you can do it either way. But note that if your tile ends on the joint, and your mudding skills are less than perfect, then you will be setting tiles on a surface that is not flat.
Most folks won't notice, but you will. Everytime you're in that bathroom.
Unless you're the lead dog, the view just never changes.
So that provides a third and perhaps better option?:
Run durock past where the tile ends, pick up with greenrock and then tape that joint with FG tape. Makes sense to me.
Do you use greenrock or just regular rock with a good primer and finish?
I like to extend the CBU past the point where tile will end. But you have to be able to float mud pretty good to make it look pretty. If not, meet the 2 pieces just inside the tile line. As long as it's not going to get too wet there, you'll be OK.
And I always use green board in a bath. (On the walls only)
I'm a fair taper, but slow. I like the idea of no stray water from the shower soaking even greenboard at the edge.
I'm assuming sheetrock mud sticks to CBU pretty good.
I've had no problems doing it. Primes and paints fine. Have even done a few sections of 10 square feet or so.
Use hotmud and not regular JC for that joint. use durabond 210 or 300(longer open time), its damn near industrutable. However its caveat is that it sands like granite.
Id go with blueboard rather then greenboard. It holds up to water better due its design for plaster veneers which is water intense. I dont think id ever use greenboard again. You could seal the rock with a thinned down type2 PVA glue (thinned 5pts water 1 part glue) Green board is pretty and makes the customers happy but in all reality its not that great, blueboard would be a better choice then use a high quality primer/sealer.
I do the opposite. I end the backerboard and span the joint between the CBU and drywall with tile, so that a half inch or so of tile bridges that joint. That joint is taped and mudded with regular drywall tape. The other CBU joints one uses the special tape and thinset, OK?
Regards,
Boris
"Sir, I may be drunk, but you're crazy, and I'll be sober tomorrow" -- WC Fields, "Its a Gift" 1934
hey .. we almost agree 100% again ...
I like the have that joint break about midpoint of the last tile ...
but ... I mesh and thinset the joint.
But ... for times .. like say when the tile layout completely changes after the cbu's are installed .... the cbu's can be flattened rather nicely with durobond as also mentioned above ...
JeffBuck Construction Pittsburgh,PA
Artistry in Carpentry