We used to require the 2.5 pounds/sf as part of the building permit application, if sprinkler permit application was a deferred permit.
We also required the structural engineer to state restrictions on point loads. Before ESFR the common sprinkler designs were 0.39 gpm/sf over 5,600 sf or 0.495/sf over 2,000 sf. Ron G will back me up on that. These worked for a 2-1/2 or 3” grid. In fact they were a little conservative; Conservative is what you get with deferred submittal. Add in lightweight steel roof and often the structural engineer would reduce hanger bracing to 10’ and sway bracing to 20’ min. Not intuitive to a non-engineer they were sometimes not concerned with longitudinal spacing. During construction booms I wasn’t a fan of lightweight metal roofs. It was not unusual to spend two or three hours on the phone with different people with the sprinkler firm, sometimes the building owner with just this issue. Bid without increased spacing. If more time than this, or particularly vehement, I’d ask inspector to stop by. Yep, already installed per submitted plan. Meanwhile every other plan review is waiting in my in basket. Best. Bruce Verhei > On 02/16/2021 7:15 PM AKS-Gmail-IMAP via Sprinklerforum > <[email protected]> wrote: > > > 5 lbs/sf collateral load is likely the low bid metal building design. This > loading is intended to include ALL the MEPF and Arch. loads on the structure. > The sprinkler contribution to the 5 lbs/sf is maybe 1.5 lbs/sf. This loading > gets used for sizing the main structural elements. Depending on the piping > layout, sizes, pipe spacing and max hanger spacing the low bid design purlins > might be undersized for some systems and max. hanger spacing. > > Note, some metal buildings are specified and bid out prior to the building > MEPF and Arch. loading being determined. Then you have situations where young > people without adequate supervision are running the metal building software > design programs. They may not know how lightweight the design is. This might > give you some context as what is going on. For sure the collateral numbers > are average loads over the entire roof area. The loads cannot account for > where there might be a large main and that is just for fire protection. The > loading does not size for other concentrated loads like HVAC equipment. If > there is seismic involved, the structure would not necessarily handle system > bracing loads at locations where NFPA 13 dictates. > > > On Feb 16, 2021, at 1:34 PM, Matt Grise via Sprinklerforum > > <[email protected]> wrote: > > > > When I have looked at it (usually for pre-engineered metal buildings)- the > > lbs/sf is just the weight of the water-filled pipe divided by the are it > > 'covers'. Similar to the coverage of a sprinkler head. > > > > Each structural member then has an allowable point-load formula based on > > how the connections are spaced and how much load it can handle. > > > > Most of the PEMB designs I come across have a 5 lbs/ft "collateral load" > > design. We have never had a sprinkler system exceed that. > > > > Matt > > > > -----Original Message----- > > From: Sprinklerforum <[email protected]> On > > Behalf Of Vince Sabolik via Sprinklerforum > > Sent: Tuesday, February 16, 2021 1:23 PM > > To: Travis Mack via Sprinklerforum <[email protected]> > > Cc: Vince Sabolik <[email protected]> > > Subject: Re: MORE ACTIVITY WEIGHING IN > > > > Offices. > > > > I'm looking for a table that an architect or engineer would use to figure > > roof loading. > > I don't think they're that detailed. > > > > > > On 2/16/2021 2:17 PM, Travis Mack via Sprinklerforum wrote: > >> What is a typical system? Protecting flammable liquids will be a lot more > >> than an office building. > >> > >> Travis Mack, CFPS, CWBSP, RME-G, COC, SET > >> Engineering Manager > >> MFP Design > >> 3356 E Vallejo Ct > >> Gilbert, AZ 85298 > >> 480-505-9271 ext. 700 C: 480-272-2471 > >> mailto:[email protected] > >> https://linkprotect.cudasvc.com/url?a=https%3a%2f%2fwww.mfpdesign.com&c=E,1,LWPOkuQfKyi4ROGqKcnbYQjv2Y6W-GC52ALx7gZ_ozT4hvUsEfdfMFU1zDo69tl0F8jhudt85K7GliMneCJSs-0mA2XIq4vv7cNfCaG8A7EfttrZ5KDqiwaXUQ,,&typo=1 > >> > >> Send large files to us via: > >> https://na01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.hightail.com%2Fu%2FMFPDesign&data=02%7C01%7C%7C1121d49f9e6b4cf248f108d4df580e77%7C14e5497c16da42e69ffa77d19bafe511%7C0%7C0%7C636379016677342180&sdata=eGdMZGu2wXhUupGwgGTrqF3b54OP5%2BAZvlHhABSexWY%3D&reserved=0 > >> > >> From: Sprinklerforum <[email protected]> On > >> Behalf Of Vince Sabolik via Sprinklerforum > >> Sent: Tuesday, February 16, 2021 12:16 PM > >> To: [email protected] > >> Cc: Vince Sabolik <[email protected]> > >> Subject: MORE ACTIVITY WEIGHING IN > >> > >> Hello forum - > >> > >> Does anyone have tables of how much weight per square foot a typical > >> sprinkler system adds > >> to a building? > >> > >> thanks, Vince > > > > > > -- > > > > 11351 Pearl Road / Suite 101 > > Strongsville, Ohio 44136 > > Phone 440 238-4800 Fax 440 238-4876Cell 440 724-7601 > > > > / > > Vince Sabolik / > > > > _______________________________________________ > > Sprinklerforum mailing list > > [email protected] > > https://linkprotect.cudasvc.com/url?a=http%3a%2f%2flists.firesprinkler.org%2flistinfo.cgi%2fsprinklerforum-firesprinkler.org&c=E,1,NPrDsZFoJHdeIk_5-R2AUIsPqjilTuTkcD587y6E7Dx0b5oQNOxLX8krqo5dLEReyOSkeIodEc43NE1QVoQjLFnVHztKtqX9EhY213_EzJPT69DC&typo=1 > > _______________________________________________ > > Sprinklerforum mailing list > > [email protected] > > http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkler.org > > _______________________________________________ > Sprinklerforum mailing list > [email protected] > http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkler.org _______________________________________________ Sprinklerforum mailing list [email protected] http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkler.org
