Where the access is located in a ceiling minimum unobstructed headroom in the attic space shall be 30 inches 762 mm at some point above the access measured vertically from the bottom of ceiling framing members.
Ibc attic access requirements.
Contributes to but does not supersede thermal resistance requirements for attic and roof assemblies in section c402 2 1 of the international energy conservation code.
The international code council icc is a non profit organization dedicated to developing model codes and standards used in the design build and compliance process.
The 2012 international residential code requires an attic access opening for attics with an area greater than 30 square feet and a vertical height in excess of 30 inches.
1202 4 under floor ventilation the space between the bottom of the floor joists and the earth under any building except spaces occupied by basements or cellars shall be provided with ventilation in accordance with section 1202.
An opening not less than 20 inches by 30 inches 559 mm by 762 mm shall be provided to any attic area having a clear height of over 30 inches 762 mm.
See section m1305 1 3 for access requirements where mechanical equipment is located in attics.
2009 ibc commercial construction requirement for attic space access 1209 2 attic spaces.