Designing Kitchens and Bathrooms - Drywall behind shower in bathroom

We've tore out the shower in our bathroom and found just normal gypsum board behind the shower, not greenboard.

Questions:

1) Do we need sheetroom behind the shower? I believe I've heard some showers need sheetrock behind them while others don't, maybe because of the gauge of plastic and rigidity of the shower.

2) If we need sheetrock, should we use greenboard or something else?

Thanks!!

sx460,

I am assuming you are talking wall surround kits over drywall. If this is an exterior wall, standard drywall is used and W/R is not recommended. All other areas can use W/R.

If we are talking a rigid wall surround - these are attached directly to the studs. You can then use W/R or standard accordingly.

So how does one prevent problems and what to use?

In areas to be tiled, treat all fastener heads with SHEETROCK® Setting-Type Durabond 45 or 90) or Lightweight Setting-Type (Easy Sand 45 or 90) Joint Compound. Use the same joint compound with SHEETROCK® Joint Tape to finish joint. For areas not to be tiled, embed tape with SHEETROCK® Setting-Type (Durabond 45 or 90) or Lightweight Setting-Type (Easy Sand 45 or 90) Joint Compound in the conventional manner.

W/R Panels for use in commercial and residential interior areas not subject to excessive or continuous moisture

– An economical moisture-resistant base for adhesive application of tile and plastic-faced wall panels
– Water-resistant face paper, core, and back paper

Description:

Although SHEETROCK® Brand Gypsum Panels—Water-Resistant, provide a moisture resistant base for adhesive application of ceramic and plastic tile and plastic-faced wall panels, they are not designed for use in high-moisture areas such as tub and shower surrounds. When installed and maintained correctly they help to minimize problems in bathrooms, powder rooms, kitchens, and utility rooms related to incidental moisture exposure.
Panels are manufactured using a 100% recycled green multi-layered face paper treated to resist moisture; a water resistant gypsum core, and a 100% recycled multi-layered back paper treated to resist moisture. The panels have
shallow tapered edges and are available in three types: 1/2 panels are available with a regular core for use in non- fire rated applications, and with a FIRECODE® C Core for use in fire-rated assemblies. 5/8 panels are available with a FIRECODE® or FIRECODE® C Core for use in fire-rated assemblies.
Limitations General

1. Do not use in tub or shower surrounds, or other areas subject to constant or excessive moisture. DUROCK® Brand Cement Board or AQUA-TOUGH™ Brand Interior Panels are recommended for these applications (see USG system folder SA932).
2. Do not expose to sustained temperatures exceeding 125 °F (52 °C).
3. Avoid excessive or continuous exposure to moisture during delivery, storage, handling and installation. Eliminate sources of moisture immediately.
4. Use adhesive (mastic) materials to apply tile. Do not use mortar-type materials.
5. When applied on ceiling, framing must be 12 o.c. maximum for 1/2 thick panels and 16 o.c. maximum for 5/8 thick panels.
6. When used as a base for tile, fasten panels through to framing (wood or steel).
7. Single-layer application on resilient channels is not recommended where tile is to be applied.
8. Panels to receive tile or other surfacing acting as a vapor retarder should not be installed over a vapor retarder.
9. On wall applications, maintain a gap of 1/4 to 1/2 inch between the bottom edges or ends of the panels and the floors, or any other horizontal surface where water could accumulate.

Do not use drywall screws or drywall nails and do not use 5/16" DUROCK Brand Underlayment for wall or ceiling applications.

Approved fasteners include: 1. DUROCK Brand Screws, USG Sheathing, Type WF for woodframe or Type SF for steel-frame construction, or 2. Minimum (1-1/2") 11 gauge, hot-dipped galvanized roofing nails with nominal 7/16" dameter head for wood framing.

I called USG to clarify issues of W/R board and use of vapor barriers. Please review this link for the information I received.

http://dougaphs.smugmug.com/gallery/251530

What products can be used in high moisture areas such as tub/shower surrounds, gang showers, or other areas?

DUROCK® Brand Cement Board is the best product for these areas. It is extremely moisture durable and offers mold resistance. The Tile Council of America does not recommend the use of paper faced gypsum substrates in these areas. USG supports this recommendation therefore we do not recommend that SHEETROCK® Brand Gypsum Panels, Water-Resistant or SHEETROCK® Brand HUMITEK™ Gypsum Panels be used in these areas.

Where should SHEETROCK® Brand Gypsum Panels, Water-Resistant be used?

SHEETROCK® Brand Gypsum Panels, WR are for interior areas where incidental moisture is a concern, but where added mold resistance is not a requirement.

Hope this helps!

Wow! Thanks for the great information Doug, I really appreciate it! You've answered all my questions. Have a great day! :)

sx460,

You're very welcome!

You have a great one as well!