Extended Sidewall Head

[sia101]

Hello

I have a situation. I am working on a sprinkler drawing for a chapel building built around 1960. Roof is pitched 30 degree down from the center ridge on which 18" deep beams are spaced every 15ft. The ceiling is built in flat wood panels. The elevation of highest peak is 30 ft.


We have been told by the owner to use extended sidewall head along one side of a beam to discharge across the slope to cover the entire 15ft bay.

Are there commercial extended sidewall sprinkler heads listed for the slope?

Can anyone please recommand me one model?

Thanks

 

[SprinklerDesigner2]

I don't know of any.

Fact be I think you are out of luck.

From NFPA #13 - 2002
8.4.3 Extended Coverage Sprinklers. Extended coverage sprinklers shall only be installed as follows:
(1) Unobstructed construction consisting of flat, smooth ceilings with a slope not exceeding a pitch of one in six (a rise of two units in a run of 12 units, a roof slope of 16.7 percent)
(2) Unobstructed or noncombustible obstructed construction, where specifically listed for such use
(3) Within trusses or bar joists having web members not greater than 1 in. (25.4 mm) maximum dimension or where trusses are spaced greater than 7½ ft (2.3 m) on center and where the ceiling slope does not exceed a pitch of one in six (a rise of two units in a run of 12 units, a roof slope of 16.7 percent)
(4) Under smooth, flat ceilings that have slopes not exceeding a pitch of one in three (a rise of four units in a run of 12 units, a roof slope of 33.3 percent), where specifically listed for such use

Seeing as how a one in three slope is 14 degrees and you being at 30 and all.