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attic access for insulation inspection and whatever

bill1952

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Aug 12, 2021
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Clayton NY
IRC 2018: R807.1 The rough-framed opening shall be not less than 22 inches by 30 inches (559 mm by 762 mm) and shall be located in a hallway or other location with ready access. Where located in a wall, the opening shall be not less than 22 inches wide by 30 inches high (559 mm wide by 762 mm high).

Rough opening or finished? It kind of says both. This is an unfinished no storage attic over habitable space, and the access has to be from the exterior through a gable. And can the 30" be horizontal so it fits through truss and bottom is above blown in?
 
R807.1 Attic access. Buildings with combustible ceiling or roof construction shall have an attic access opening to attic areas that have a vertical height of 30 inches or greater over an area of not less than 30 square feet. The vertical height shall be measured from the top of the ceiling framing members to the underside of the roof framing members.

The rough-framed opening shall be not less than 22 inches by 30 inches and shall be located in a hallway or other location with ready access. Where located in a wall, the opening shall be not less than 22 inches wide by 30 inches high. Where the access is located in a ceiling, minimum unobstructed headroom in the attic space shall be 30 inches at some point above the access measured vertically from the bottom of ceiling framing members. See the California Mechanical Code for access requirements where mechanical equipment is located in attics.
 
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I think it should be as close as practicable to 22" x 30". My guess is that the code just gives rough opening sizes because most access openings are in the ceiling, and almost all of them don't have any finish jambs, just 1/2" or so stops (or the trim projects about 1/2" inside the rough opening).
 
I think it should be as close as practicable to 22" x 30". My guess is that the code just gives rough opening sizes because most access openings are in the ceiling, and almost all of them don't have any finish jambs, just 1/2" or so stops (or the trim projects about 1/2" inside the rough opening).
I don't disagree but wouldn't it be better for everyone to simply say what the minimum clear opening was to be? That kind of unclear code writing is just irritating.

I imagine in fact if an inspector can see the measure strips and have a fair idea of the depth of insulation, there isn't a lot to write up. I doubt too many attic openings are red tagged.
 
I don't disagree but wouldn't it be better for everyone to simply say what the minimum clear opening was to be? That kind of unclear code writing is just irritating.

I imagine in fact if an inspector can see the measure strips and have a fair idea of the depth of insulation, there isn't a lot to write up. I doubt too many attic openings are red tagged.
Bill,

This is no different than the rough window sill height, it needs to be checked at the framing inspection, thus will a finished clear be checked at framing, I doubt it.

Thus, if you know the rough opening is there, and the minimum size is there, the odds on someone closing it down more than trimming it out is a better bet.
 
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