Tub-to-Shower Conversion: The Complete Materials Checklist

What a tub-to-shower conversion really involves

Replacing a bathtub with a walk-in shower is one of the most common bathroom remodels, but it's also one of the projects most people underbuy for. Beyond the obvious — a new shower pan or tile deck — you're rebuilding the drain rough-in, waterproofing behind the walls, upgrading the mixing valve, and often replacing sub-flooring where the tub sat.

This guide covers the material categories Matly recommends when it generates a scope from a photo or contractor quote. It's not a step-by-step build — it's a checklist so you don't get to day-three and realize you're missing the pre-slope mud, curb, or a compatible drain.

Rough plumbing

• Shower valve + trim kit (Delta, Moen, or Kohler — verify the trim matches the rough-in body)
• PEX or copper supply lines — match your existing plumbing
• Shower drain assembly (linear or center) with a compression or solvent-weld connection
• P-trap + 2" DWV pipe + fittings — check whether your original tub drain is 1½" and needs upsizing
• Shark-bite or press fittings for tight retrofit work

Pan + waterproofing

• Pre-slope mud (deck mud, sand-topping mix) — usually 3–4 bags for a 60" opening
• Waterproofing membrane (Kerdi, Wedi, or RedGard) — sheet or liquid, but don't mix systems
• Curb — pre-formed foam curb or 2×4 wrapped in membrane
• Corner + seam patches for the waterproofing system you chose
• Backer board (½" HardieBacker or 5/8" Wedi board) on the shower walls

Tile + finish

• Tile — order 15% overage for cuts and future repairs. For herringbone or diagonal patterns, order 20%.
• Thin-set — modified for porcelain over cement board, unmodified over Kerdi
• Grout + sealer — epoxy grout on the floor, sanded/unsanded cementitious on walls per joint width
• Shower door or curtain rod — measure opening before ordering
• Niche(s), corner shelves, curb tile, Schluter edge trim

Common mistakes Matly catches

• Buying a valve trim kit that doesn't match the rough-in body brand
• Ordering tile without adding waste factor
• Skipping the pre-slope — grout lines will pool water
• Mixing waterproofing systems (Kerdi membrane + RedGard corners = warranty voided)
• Forgetting the transition strip at the bathroom floor