Convince me to use kerdi board instead of kerdi membrane over drywall.
Speed, cost, I’m old and lazy, I have carried an entire 5/8x10’ tall Kerdi board shower wall system up the outside porch of a 3 story home in one trip.
Easier to wet shim the Kerdi board than drywall.
When it comes to the bench, I have to look but I think I’m at $70. A sheet for 2x8x2 Kerdi board, I get the bench and the curb out of it normally. This cheaper than most of the benches alone. It you need to make a stem/pony wall Kerdi fix two sheets together, no studs needed. Easy to carve in a niche also.
If you’re going to use Kerdi over the drywall, spray the drywall with water from a pump sprayer. I lap the Kerdi 2” around corners, no banding needed in the corners.
Some will say that the patches and seams take to long and you have to mix mortar. There is a process to all the other systems so I consider it a wash. If you’re doing a flood test (as you should) what does it matter? It’s day lost any way you look at it.
I don’t band the pan to the walls, I cut the pan Kerdi, 4” larger each direction, fold at the 2” marks and set the liner, this takes care of the pan to wall seam. Kerdi band and corners for the rest of the install. For the washers/screws, you can run a band strip saving cutting time, the screws should be aligned on the studs (I hope...). Other option is wrap the band around your hand about 5 times, slide off have, cut at rolls that form as you flatten it, this will yield 10 pieces each time.
You’ll learn to deal with the build up, if you have to really thin the mortar for corners, do it, 2 4” taping knives are your friend, one to tuck and hold, one to strike.
Tom
