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Brent Crouse
05-12-2008, 06:58 PM
Firestopping is required in a garage on any wall/ceiling which has livable space on the other side. This is usually provided via drywall.

Question: Can the ceiling drywall be omitted if a sprinkler system is installed?

Thanks.

Jerry Peck
05-12-2008, 07:10 PM
Firestopping is required in a garage on any wall/ceiling which has livable space on the other side. This is usually provided via drywall.

Brent,

First, that is not "firestopping", that is "separation". It is not even a "fire rated ceiling".


Question: Can the ceiling drywall be omitted if a sprinkler system is installed?

Nothing says it can be eliminated.

Besides, why would you want to?

That would expose all the insulation underneath the floor above to the garage side, and, it would also increase (make if much more difficult to eliminate or reduce) air infiltration and exfiltration.

Brent Crouse
05-12-2008, 07:18 PM
Thanks for the speedy reply.

I saw a townhouse (built in 2004) with an exposed garage ceiling, with just insulation. It has a sprinkler system installed on the ceiling, but that's it. I wasn't sure if this was a valid method of fire separation or not. I think they did it because some of the a/c ducting runs across the garage ceiling, which would then drastically reduce the headroom if a drywall ceiling were installed.

Brent Crouse
05-13-2008, 06:21 AM
Just talked to the local Cobb county code office, and they said that although not ideal, this setup is acceptable. The theory being that the purpose of fire separation is not to be a fire stop, but to slow down the spread of fire, which the sprinkler system would accomplish.

Bob White
05-13-2008, 08:25 AM
Yep.

Georgia's version of the 2000 IRC was amended in Jan 2002 to add an exception to to Section R309.2 to read:

"Section R309.2 Separation required.
Exception:
In garages protected by an automatic sprinkler system installed in accordance with NFPA 13D, a separation is not required.
(Effective January 1, 2002)"

The newly adopted IRC 2006 has been amended to read:






GARAGES AND CARPORTS


*Revise Section R309.2 ‘Separation required’ to add exceptions as follows:



R309.2 Separation required.



Exception #1:


Separation is not required in garages protected by an automatic sprinkler system that meets the following criteria:
1. Maximum protected area is 600 square feet (55.74 m2).
2. Maximum number of sprinkler heads per domestic system is six.
3. Minimum pipe size supplying domestic water system shall be ¾-inch (19 mm) nominal diameter.
4. Maximum area of coverage per sprinkler head of 100 square feet (9.29 m2).
5. No control valve to isolate the sprinkler head(s) unless supervised.
6. Protected area is defined by physical barriers that extend from floor to ceiling of construction that will resist the passage of smoke.
7. Doors through physical barriers shall be equipped with self-closing devices and be positive-latching.
Exception #2:
A disappearing/pull-down stairway with minimum 3/8-inch (9.53 mm) (nominal) fire-retardant-treated structural panel is deemed to meet the 20-minute thermal barrier test based on ASTM E 119, Test Methods for Fire Tests of Building Construction and Materials, or deemed to have the fire resistance of or equivalent to ½-inch (12.7 mm) gypsum wall board.



(Effective January 1, 2007)


Exception #2 was added to the old 2000 IRC by Georgia in 2005.

Brent Crouse
05-13-2008, 08:51 AM
Thanks for the help Jerry and Bob!!! Appreciate it.