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Attic separation

Attic separation

New postby bigdog on Tue Jan 15, 2013 9:43 am

Hi Jerry
I just looked at a duplex here in Palm Beach County, Masonry walls and trusses..built in 1973 with no fire / draft stopping between the units in the attic.
Do you know when this requirement was put into effect?
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Re: Attic separation

New postby Jerry Peck - Codeman on Tue Jan 15, 2013 7:33 pm

I am not exactly sure when that was required (I am not at my computer with my older codes on it); however, that requirement was applicable in all of the areas I can recall, and was applicable going back decades ... but was not enforced going back decades; i.e., there are many duplexes from the 1960s and 70s in Broward County and Miami-Dade County which did not have the required fire-resistance rated wall in the attics, and, like you, I have seen the same thing in Palm Beach County. I believe it was in the codes at that time, it's just that 'fire' was not of 'high importance' until the mid-to-late 1980s.

Palm Beach County used to be under the old Standard Codes from the Southern Building Code Congress International (SBCCI) and, to my recollection, that fire-resistance rated wall was required.

There is an exception in the current Florida Building Code (however, you would find a draftstopping wall instead of a firewall for the exception to apply):
- R302.3 Two-family dwellings.
- - Dwelling units in two-family dwellings shall be separated from each other by wall and/or floor assemblies having not less than a 1-hour fire-resistance rating when tested in accordance with ASTM E 119 or UL 263. Fire-resistance-rated floor-ceiling and wall assemblies shall extend to and be tight against the exterior wall, and wall assemblies shall extend from the foundation to the underside of the roof sheathing.
- - - Exceptions:
- - - - 1. A fire-resistance rating of 1/2 hour shall be permitted in buildings equipped throughout with an automatic sprinkler system installed in accordance with NFPA 13.
- - - - 2. Wall assemblies need not extend through attic spaces when the ceiling is protected by not less than 5/8-inch (15.9 mm) Type X gypsum board and an attic draft stop constructed as specified in Section R302.12.1 is provided above and along the wall assembly separating the dwellings. The structural framing supporting the ceiling shall also be protected by not less than 1/2-inch (12.7 mm) gypsum board or equivalent.
- - - - 3. Screen enclosure walls of insect screening with a maximum of 25 percent solid flexible finishes.
- - R302.3.1 Supporting construction.
- - - When floor assemblies are required to be fire-resistance rated by Section R302.3, the supporting construction of such assemblies shall have an equal or greater fire-resistance rating.

All the above said, though, and for your case, the critical aspect is that there is no fire-resistance rated wall there and there should be, for the safety of the occupants in each duplex.
Jerry Peck - CodeMan
Construction Litigation Consultant - Retired
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