Attic Access Hatch Minimum Size

If the attic space is smaller than these specs then an access hatch is not required.

Attic access hatch minimum size.

These specs are per r807 1 of the international residential code irc and the residential edition of the florida building code fbc. Minimum opening size 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. The rough framed opening must be a minimum of 22 inches by 30 inches. According to the 2006 international residential code r807 1 attic access homes with combustible materials in the ceiling and roof construction must have an access to attic areas that exceeds 30 square feet and with a vertical height of 30 inches or greater.

If the access is located in the ceiling the minimum unobstructed headrom above the opening must be 30 inches measured vertically at some point over the access. Minimum vertical height of 30 inches measured from the top of the ceiling framing members to the bottom of the roof framing members. The 2007 california building code requires a minimum attic access opening of 20 inches by 30. The access opening should be located in a hallway or other readily accessible location and minimum 22 x 30.