I. Floor Finish Materials

Floor finish materials shall be smooth, hard, and non-absorbent. The following are examples of acceptable floor finish materials:

1. Portland cement
2. Concrete (troweled smooth)
3. Ceramic tile (glazed or unglazed)
4. Terrazzo (cement base)
5. Marble blocks or slabs
6. Sheet vinyl with fully-coved or top-set base
7. Magnetite composition
8. Approved prefabricated shower pans or stalls

II. Wall Finish Materials

Wall finish materials shall be smooth, hard, and non-absorbent. The following are examples of approved wall finish materials:

1. Concrete or concrete block covered with waterproof paint or plastic
2. Portland cement plaster on metal lath, wire lath, or wire fabric, troweled smooth and painted
3. Prefabricated metal toilet compartment partitions (painted) or approved prefabricated shower stalls
4. Glass mat water resistant gypsum backing panels, Nonasbestos fiber-cement backer board or Nonasbestos fiber-mat reinforced cementitious backer unit (CBC 2509.2)
5. Ceramic, plastic or enamel finish metal tile
6. Marble or simulated marble slabs or blocks
7. Stainless steel
8. Tempered masonite with factory-applied baked paint or plastic.

III. Showers

Walls finishes, as specified in Section II of this technical bulletin, in shower compartments and in bathtubs with installed shower heads shall extend to a height of at least 72 inches above the drain inlet.

IV. Backing Materials and Methods

The following backing methods are examples of acceptable installation of wall finish materials listed in Section II of this technical bulletin, items 4 through 8:

1. Portland cement plaster applied to framing in accordance with exterior plaster application method.
2. Three-eighths (3/8”) inch exterior grade plywood (Grade C-C) minimum, or interior grade plywood with exterior glue applied to framing as a backing. All joints must be caulked.
3. Walls in bathrooms other than walls surrounding showers and bathtubs may use water-resistant board such as cement backerboard.

V. Water Closet Compartments

In other than dwelling units and in toilet rooms that are not accessible to the public, walls and partitions within 2 feet of sinks, urinals and water closets shall have a smooth, hard, non-absorbent surface, to a height of not less than 4 feet above the floor. Refer to Section II of this technical bulletin for a list of acceptable wall finish materials. All materials shall be installed in accordance with manufacturer’s specifications and CRC, Chapter 7, or CBC, Chapter 25, as applicable.

All wall surfaces not specifically requiring protection against water intrusion and water splash as outlined in CBC Section 1209.2 and CRC R307.2 may be finished with gypsum lath and gypsum plaster, troweled smooth and painted. Water-resistant gypsum backerboard may be applied as a base for tile or wall panels in water closets in accordance with American Society for Testing and Materials (ASTM) C840 or Gypsum Association GA-216 (CBC Section 2509.2). Refer to CBC Section 2510.6 for restrictions on the use of wood-based sheathing as a backing for plaster.

VI. Privacy Partitions

Public restrooms shall be visually screened from outside entry or exit doorways to ensure user privacy within the restroom as outlined in CBC section 1210.3. This provision is also applicable where mirrors would compromise personal privacy.

Privacy at water closets shall be in accordance with CBC section 1210.3.1, where it shall occupy a separate compartment with walls or partitions and a door enclosing the fixtures to ensure privacy.

Privacy at urinals shall be in accordance with CBC section 1210.3.2, where it shall occupy a separate area with walls or partitions to provide privacy. The walls or partitions shall begin at a height not more than 12 inches from and extend not less than 60 inches above the finished floor surface. The walls or partitions shall extend from the wall surface at each side of the urinal not less than 18 inches or to a point not less than 6 inches beyond the outermost front lip of the urinal measured from the finished backwall surface, whichever is greater.

VII. Unacceptable Materials

The following materials are examples of not acceptable for use as a finished surface:

1. Asphalt or vinyl tile
2. Wood or wood products (exception: tempered masonite)
3. Gypsum board of any type including wallboard, sheathing, and gypsum lath
4. Gypsum plaster, including Keene’s cement plaster

VIII. Inspections

At the time of drywall inspections, the sealing of all cut edges, utility holes and joints will be inspected.