Hatches in rated ceilings / assemblies

[bigdog]

What is the minimum material for an attic hatch in residential? Seems like it should be equivalent to the ceiling rating. I see everything from 1/2 drywall to plywood to drywall and plywood with sheet metal on the living space side. Also if you could include the appropriate code reference I would appreciate it.

David

[Jerry Peck - Codeman]

Living space or garage attic access?

The living space attic access would need to be of a material which meets the energy code - there is no fire rating to ceilings in one- & two-family dwellings and townhouses.

The garage ceiling in the same structures do not have a fire rating either ... however ... the garage is required to be separated from the living space and its attic.

The garage can be separated from the living space and its attic in two basic ways:
- extend the garage/living space wall all the way to the underside of the roof decking to separate the living space attic from the garage, the garage does not require a ceiling in this case
- install a ceiling in the garage which separates the garage from its attic, the garage attic and the living space attic does not require separation in this case
- the separation is required to be 1/2 inch gypsum board minimum (or equivalent) for the above separation ... plywood, metal, etc is not an equivalent
- any opening in the drywall needs to maintain the same level of separation as the minimum 1/2 inch gypsum board provides

[bigdog]

So to be clear you are saying that in a bedroom closet the attic hatch could be 1/4" plywood as long as its insulated to code above and has weatherstripping to seal the opening?

Is there a table in the code to determine fire rating "equivalency" in materials?

David

[Jerry Peck - Codeman]