AS Hydraulic cals for Large DC's
AS Hydraulic cals for Large DC's
(OP)
Hi,
Are hydraulic calculations required for every sprinkler system in a large Distribution Center (or similar) where there are many systems, each having the same designs and piping layouts. I seem to see more and more submittals where only the most remote system (furthest from the water supply) is calc'd then that demand is put on all placards. Systems are generally very similar but are not always identical - some are smaller than others which would likely result in a lower demand (assuming the same design). I know that if the supply is adequate for the most remote system, then it would be okay for closer systems, but I would rather see calcs for each system but I can't find a reference in NFPA or FM that provides clarification. Maybe they're not necessary?
Thanks for your time,
Wally
Are hydraulic calculations required for every sprinkler system in a large Distribution Center (or similar) where there are many systems, each having the same designs and piping layouts. I seem to see more and more submittals where only the most remote system (furthest from the water supply) is calc'd then that demand is put on all placards. Systems are generally very similar but are not always identical - some are smaller than others which would likely result in a lower demand (assuming the same design). I know that if the supply is adequate for the most remote system, then it would be okay for closer systems, but I would rather see calcs for each system but I can't find a reference in NFPA or FM that provides clarification. Maybe they're not necessary?
Thanks for your time,
Wally





RE: AS Hydraulic cals for Large DC's
Not sure if 13 would address this situation
RE: AS Hydraulic cals for Large DC's
RE: AS Hydraulic cals for Large DC's
RE: AS Hydraulic cals for Large DC's
RE: AS Hydraulic cals for Large DC's
Chapter 23 23.1* Working Plans.
Plans and Calculations
23.1.1* Working plans shall be submitted for approval to the authority having jurisdiction before any equipment is installed or remodeled.
(34) Hydraulic reference points shown on the plan that correspond with comparable reference points on the hydraulic calculation sheets.
How can you comply with the above section by only submitting a few calculations?
One of the 1st things I do in the plan review process is make sure I have calculations for each system, if not, I reject and referance the above section.
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RE: AS Hydraulic cals for Large DC's
RE: AS Hydraulic cals for Large DC's
Wally
RE: AS Hydraulic cals for Large DC's
If I have a 6 story hotel, where floors 2-6 are identical, would I need to provide calculations for every floor, or just calculate Level 6 and size the others based on level 6 calcs? I often run calcs on a lower floor just to see if I can reduce pipe sizes, but if I can't, then I don't bother submitting that calc.
Travis Mack
MFP Design, LLC
www.mfpdesign.com
RE: AS Hydraulic cals for Large DC's
RE: AS Hydraulic cals for Large DC's
Personally I would calculate the most remote/demanding and then see if the pipe sizes could be reduced to save money on the remainder of the systems. Otherwise it just seems to be using extra paper.
RE: AS Hydraulic cals for Large DC's
RE: AS Hydraulic cals for Large DC's
But pipe between the source and base of riser was not typical so I ended up with 24 sets of calculations enough to fill a phone book. They all came out close but non were identical.
Gridded ESFR side fed systems so why did I end up with two sets of calculations per system?
Building was 200'x200' with 24' eave and 1 in 12 pitch to the peak at center of the center of the building. Sprinklers adjacent to peak were 7'-6" higher than sprinklers along the eave and that made a difference by a good couple of pounds putting my hydraulically most demanding area not at the far end of the system where most would think it would be but halfway back toward the riser smack in the middle of the system. So I submitted two sets; one showing the most remote where some might expect it to be the other showing where it actually was knowing if I didn't show where it was expected to be there would have been questions my the local AHJ.
Gentlemen, if you got systems that straddle peaks where cross mains are rather large you really should do two sets of calcs because it might just surprise you.
RE: AS Hydraulic cals for Large DC's