Building codes require that crawl spaces be made accessible the 2012 irc describes the minimum crawl space accessibility requirements as follows.
Minimum attic access opening.
These openings not only allow mechanical and electrical contractors to.
In buildings with combustible ceiling or roof construction an attic access opening shall be provided to attic areas that exceed 30 square feet 2 8m2 and have a verti cal height of 30 inches 762 mm or greater.
The minimum opening for the attic access should be 22 inches by 30.
When located in a wall the opening shall be a minimum of 22 inches wide by 30 inches high 559 mm wide by 762 mm high.
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.
508mm is 20 inches was no typo on the scuttle or access opening minimum.
Access shall be provided to all under floor spaces.
The compact attic ladder requires a minimum height of 28 and minimum depth of 44 inside the attic above and behind the opening.
You re confusing the appliance gangway access passage way minimum width heighth and depth with what was the access entrance minimum or didn t catch what follow ed.
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.
Tuesday january 28 2020.
The rough framed opening shall not be less than 22 inches.
Here s the full text of the code.
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.
What is the minimum size for attic access opening.
See the california mechanical code for access requirements where mechanical equipment is located in attics.
If the opening is located in a wall the 30 inch dimension must be vertical.
The access opening should be located in a hallway or other readily accessible location and minimum 22 x 30.
If the access is located in the ceiling the minimum.
The rough opening cannot be less than 22 inches by 30 inches and must be located in a hallway or other readily accessible location.
The minimum size for an attic s access.
If the attic space is smaller than these specs then an access hatch is not required.
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 rough framed opening must be a minimum of 22 inches by 30 inches.