digest
Short Summary
Main recommendation: Install drywall in a shower by using moisture-resistant wallboard behind a waterproofing membrane, building out the wall flush with the tub's tile flange using J-trim, and cutting fixture openings with basic hand tools. The presenter argues that a waterproof membrane makes expensive "green board" or "blue board" unnecessary, since the membrane keeps the board dry.
Key Points
- The presenter contrasts common TV advice (green board and blue board) with a superior waterproofing system that keeps the board from getting wet, so costly specialty board is not worth the spend.
- The tub's integrated tile flange is thick, so the wall is built out to bring the finished wall over the flange, letting tile run straight down into the tub without awkward curves.
- Metal J-trim wraps the drywall on three sides, giving a clean tile edge and eliminating the need for mud work where the new and old drywall meet.
- The wall is prepared before closing: the water supply, faucet, tub, drain and overflow are installed, the vapor barrier is fixed, and any mold behind the wall is remediated.
- The presenter accepts a visible gap, saying it's a bigger issue elsewhere; he'll fill it with cement and cover it with cloth under the waterproofing membrane, making it rock hard with no problems.
Details Worth Noting
- Concrete instructions: Cut the back piece of wallboard first using a drywall square, scoring the paper on the outside.
- Concrete instructions: Cut the shower fixture and tub spout openings using basic hand tools; a Roto-Zip spiral cutter or hole saw kit also works, while cement backer board requires proper saw blades and tools.
- Concrete instructions: Set the tub flush to the wall, then build out the wall with strapping behind the tile flange so the drywall covers the flange.
- Concrete instructions: Use a 3/32 spacer or shim for the build-out, then cut a single piece of drywall with no joints, attach the metal J-trim to it, and install it as one panel with precise measurements.
- The presenter notes that building out creates a mismatch with the old drywall, which is accepted because the J-trim handles the finished edge.
- The presenter's planned finish: apply the waterproofing membrane, fill the ceiling gap with cement, and cover it with cloth, which he says will harden and cause no problems.
Bottom Line
A shower wall can be finished with standard drywall, provided it is fully protected by a quality waterproofing membrane and detailed with a build-out and J-trim at the tub flange.
