I'm completely remodeling our master bath, and I have a quick question.
In the shower, I'm putting up all new Durock concrete board and using
self-adhesive fiberglass tape on the flat joints. My question is, how
do I tape the inside corners? Can I use regular joint tape, or do I
need to continue with the fiberglass tape? The paper tape is scored
down the center and would be much easier to work with. Will it matter
much since tile will be going up anyway?
Use the fiberglass tape and _don't_ use
'drywall compound' to go over the tape, use
polymer modified thinset, which will make
the entire wall waterproof. Often people
will wrongly use 'drywall compound' to tape
joints in showers, then when water penetrates
and gets the wallboard moist, the compound
disintegrates and releases the tiles.
I don't tape the corners. When you tile the walls, you should not
grout the corner joint, but should use flexible sealant (like silicone
caulk) in the corner. Doing it that way allows for the slight movement
between the walls.
The tape on the flat joints is to help prevent tiles from cracking
over the seam; this can't happen in the corner if you use flexible
sealant. BTW, you should bed the tape over the flat joints in
And it's probably too late, but you should (have) put a waterproof
lining (such as building felt) behind the backer board, starting at
the bottom and with the upper pieces lapped over the lower.
HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here.
All logos and trade names are the property of their respective owners.