Required Attic Access Size
Building codes 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.
Required attic access size. A 30 inch 762 mm minimum clear headroom in the attic space shall be provided at or above the access opening. See the california mechanical code for access requirements where mechanical equipment is located in attics. 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. When 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.
For smaller attic openings with a minimum measurement of 18 x 24 you will need to measure the swing clearance inside the attic space. The following are attic furnace installation requirements based on 2009 irc and 2009 imc the codes refer to it as appliances in attics. Attic furnace passageway and service area electrical requirement. The type of attic access determines the means you can install for entrance into the attic.
The compact attic ladder requires a minimum height of 28 and minimum depth of 44 inside the attic above and behind the opening. If the attic space is smaller than these specs then an access hatch is not required. Solutions for the new code requirements r 42 attic access hatch exceeds all code requirements 22x30 pre finished white wood frame trim e zh t h triple gasketed air tight seal z hatch mark d. 2006 irc residential construction.
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. Attic furnace access passageway and platform. Here s the full text of the code. See section m1305 1 3 for access requirements where mechanical equipment is located in attics.