What type of wall surface is required above a bathtub?

What type of wall surface is required above a bathtub?

• A. Water-resistant plaster
• B. Nonabsorbent wall surface
• C. Painted drywall
• D. Vinyl paneling

Answer: (B)

Moisture control in a wet area is the main idea. Above a bathtub, walls are repeatedly splashed with water and exposed to humidity, so the surface must resist water penetration. A nonabsorbent wall surface stays dry on the interior side, cleans easily, and prevents moisture from soaking in, which reduces the risk of mold, rot, and deterioration behind the finish. That’s why nonabsorbent surfaces are required in this location. Materials that fit this requirement include things like ceramic tile, sealed gypsum board with proper backing and waterproofing, or vinyl panels. Plain painted drywall or plaster can absorb moisture and deteriorate over time if not specially waterproofed, so they’re not as suitable for the area directly above a tub.

Moisture control in a wet area is the main idea. Above a bathtub, walls are repeatedly splashed with water and exposed to humidity, so the surface must resist water penetration. A nonabsorbent wall surface stays dry on the interior side, cleans easily, and prevents moisture from soaking in, which reduces the risk of mold, rot, and deterioration behind the finish. That’s why nonabsorbent surfaces are required in this location.

Materials that fit this requirement include things like ceramic tile, sealed gypsum board with proper backing and waterproofing, or vinyl panels. Plain painted drywall or plaster can absorb moisture and deteriorate over time if not specially waterproofed, so they’re not as suitable for the area directly above a tub.