All steel of Chapter 22 shall conform to the minimum thickness of metal in accordance with Section 2211.2.
All exterior structural steel members exposed to weather shall have a minimum thickness of metal of 0.23 inches (5.8 mm).
Exceptions:
Exceptions:
- When an approved type of atmospheric corrosion- resistant steel is used.
- Exposed surfaces are zinc coated with a minimum weight of coating of approximately 0.6 ounces per square foot (0.00156 kg/m2) of exposed surface and covered with a protective coating as required by Section 2203.2.
- Exposed surfaces are protected by other means approved by the commissioner.
- Temporary construction that will be in place for a period of 1 year or less, provided that all surfaces which are exposed to the weather shall have a protective coating as required by Section 2203.2.
- Joists or purlins that are exposed to the weather but which do not support more than 200 square feet (19 m2) of floor or roof area, and which have a protective coating as required by Section 2203.2.