A closet is designed for a clothes dryer. The manufacturer’s instructions give no makeup-air specification, and no other approved makeup-air method is provided. Under 2024 IRC M1502.6.1 (published Version 2.0), what minimum total area must its permanent enclosure openings provide?
- A50 square inches
- 100 square inches
- C200 square inches
- D288 square inches
Where to look it up
https://codes.iccsafe.org/content/IRC2024V2.0/chapter-15-exhaust-systems
Why B is correct
M1502.6.1 first uses the dryer manufacturer’s makeup-air instructions. If those instructions have no specification, it permits permanent enclosure openings totaling at least 100 square inches or another approved makeup-air means. The question selects the opening route. This is closet makeup air, not the area of the dryer exhaust duct or a universal two-square-foot ventilation requirement for every dryer installation. Values greater than the minimum are not themselves too small. Source: https://codes.iccsafe.org/content/IRC2024V2.0/chapter-15-exhaust-systems