Please be aware of the definition and egress requirements of a habitable attic as it relates to dwellings built from the 2012 irc.
Attic access requirements irc.
See section m1305 1 3 for access requirements where mechanical equipment is located in attics.
Current international residential code irc 12 13 section r807 attic access.
30 x 22 however irc m1305 1 3 regarding the attic passageway access not attic access is not as clear because it uses two different dimensions in relation to the term opening used twice in the same paragraph.
Irc 807 1 is clear to me with its dimensions for attic access.
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 ventilation amount and opening size requirements can be found in section 806 roof ventilation of chapter 8 roof ceiling construction.
Attics that meet the size and ceiling height criteria of the habitable attic definition in chapter 2 are considered habitable.
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.
There you ll see that an access opening is all that is specified not stairs.
R807 1 1 attic service access.
16 georgia is bringing back a requirement that was previously an amendment to the 2006 irc which will now require attics containing appliances to be accessible by pull down stairs or other permanent stairs.
See section m1305 1 3 for access requirements where mechanical equipment is located in attics.
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.
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.
The following are the requirements taken directly from the irc.
The 2009 and 2015 irc verbiage is similar and still applicable.
2015 irc mechanical 1305 1 3 2 access for cooling or heating appliance for residential application the attic space in which any cooling or heating appliance is installed shall be provided with a permanent ladder for folding away ladder or direct access door opening from the house on the same floor level.
You will also see that for smaller attic areas no access is required whatsoever in my view some access to all such limited space areas is desirable to permit visual inspection for leaks.
See the california mechanical code for access requirements where mechanical equipment is located in attics.