Gutted an alcove shower. Replacement acrylic base is 32" x 32" Delta 40014, which has a slightly smaller footprint than the base it replaces. The instructions show base flange fastened directly to wall studs, then green/cement board coming down to top of flange, overhanging it, then finish wall coming down to top edge of shower base itself, creating a 1/2" void between flange and finished wall.

enter image description here

My finished walls will be Wilsonart WetWall, which are 1/2" panels faced with laminate. Because this shower has such a small footprint, I'm wondering if I can take a different approach, making green board parallel to the base flange, then bringing WetWall panel down flush (or nearly) against the flange. So no void. Adds an inch of space compared to the install instructions, but unsure if it could be less waterproof.

enter image description here

  • Green board is not an acceptable wall surface in a shower
    – Matthew
    Commented Jun 26, 2022 at 14:59
  • @Matthew, IIUC, the greenboard will be covered by the "Wilsonart WetWall" material, thus not directly exposed to the shower.
    – FreeMan
    Commented Jun 27, 2022 at 14:32

1 Answer 1


The void is to have some separation between the flange and the green board. You will normally have to re caulk showers after a number of years due to settling, etc. If, and when, your sealant fails, that void will prevent the water from rising up and being absorbed by the green board. Remember, this is a shower so water hitting in that area will be forceful. It will also keep water from coming in contact with the screws holding the base flange in place.

Also, think about using cement board instead of green board. It's just structurely more sound.

  • 1
    thank you. Will take your suggestions to keep the gap as designed, and probably use cement board (if only because I don't have a pickup truck to transport 4x8 sheets).
    – Scott
    Commented Jun 28, 2022 at 11:57

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.