What is the minimum height required for a nonabsorbent wall surface above a bathtub?

What is the minimum height required for a nonabsorbent wall surface above a bathtub?

• A. 4 feet
• B. 5 feet
• C. 6 feet
• D. 7 feet

Answer: (C)

Moisture control around wet areas is the key idea. The wall area above a bathtub is where splashes hit most, so finishing it with a nonabsorbent surface up to six feet above the finished floor keeps water from soaking into wood framing or porous materials. This six-foot height is the minimum that codes require to protect the structure and reduce rot and mold risk, using materials like tile, moisture-resistant drywall, or other water-resistant finishes in that zone. Choosing a height lower than six feet would leave more area exposed to moisture, while going higher than six feet isn’t required to meet the minimum standard.

Moisture control around wet areas is the key idea. The wall area above a bathtub is where splashes hit most, so finishing it with a nonabsorbent surface up to six feet above the finished floor keeps water from soaking into wood framing or porous materials. This six-foot height is the minimum that codes require to protect the structure and reduce rot and mold risk, using materials like tile, moisture-resistant drywall, or other water-resistant finishes in that zone. Choosing a height lower than six feet would leave more area exposed to moisture, while going higher than six feet isn’t required to meet the minimum standard.