Hydraulic Calcs for Sprinklers above / below Cloud Cielings
Hydraulic Calcs for Sprinklers above / below Cloud Cielings
(OP)
Do you include every sprinklers above and below a dropped cloud cieling located in the design area in the calculation?
NFPA 13 (2007) section 22.4.4.6.3 indicates that only the above or below level is required to be included in the calc.
This does not seem conservative enough since this open floor plan has rather large spaces between cloud ceilings and many sprinklers both abaove and below.
Any advice?
NFPA 13 (2007) section 22.4.4.6.3 indicates that only the above or below level is required to be included in the calc.
This does not seem conservative enough since this open floor plan has rather large spaces between cloud ceilings and many sprinklers both abaove and below.
Any advice?





RE: Hydraulic Calcs for Sprinklers above / below Cloud Cielings
Travis Mack
MFP Design, LLC
RE: Hydraulic Calcs for Sprinklers above / below Cloud Cielings
Short of any guidance from the NFPA 13 committee, the only literal way to look at it currently, is that you are first responsible for protection at the highest ceiling/deck, then, as Travis has suggested, you must add heads for any obstruction to discharge using the available rules in NFPA 13 for obstructions.
This would typically (not always) lead to adding heads into/under any "cloud" or other obstruction that is wider than 4-ft. and obstructs the heads at the higher level.
It is my personal opinion that while this position may be defendable legally, it is not necessarily supported by reality. More testing/study needs to be done to determine the effects of clouded ceilings, since it does not appear that our Architect buddies plan to stop designing them into the projects that we have to protect.