On Mon, 21 Jan 2008 13:25:12 -0800 (PST),
wrote:

Online copy of the NJ Building Code states that "Gypsum board shall be
permitted to be used on wood joists to create a horizontal diaphragm
ceiling in accordance with table 2508.5" which then states that 1/2"
Gypsum board used on framing members of 16" o.c. provides 90 plf shear
value, and on 24" o.c. provides 70 plf shear value when used with 1
5/8" wall borad nails or 1 1/4" type S or W screws.

The fire-resistance rated section of the code is simply too confusing
to understand, but they wouldn't have conflicting requirements in the
code book, would they?

Stop by, and see the local fire house Captain! Ask him/her.

Oren
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