Did you verify that the owner/ AHJ really wants new calcs? They may be in there as part of a canned spec that did not get cut out.
Matt Grisé PE*, LEED AP Sales Engineer Alliance Fire Protection *Licensed in KS & MO 913.888.0647 ph 913.888.0618 f 913.927.0222 cell www. AFPsprink.com -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Todd Williams Sent: Wednesday, January 12, 2011 6:06 AM To: [email protected] Subject: Re: Hydraulic Calcs Are you replacing only the 3" pipe or branch lines and heads as well? Was the existing system hydraulically calculated or pipe schedule? How old is the system? Depending on the age of the existing system, new hydraulics could open cans of worms. If it is pipe schedule, the system has probably never been calculated so there is no indication of how the hydraulics looked in the first place. If it has been calculated, was the 30% increase for dry systems, 30% increase for roof slope and the new(er) minimum end head pressures included? If not, you may not have an adequate system, based on current Code. But it may have been fine when it was installed. Is there a compelling reason to bring this attic up to current Code? This probably needs to be hashed out between you, the Owner, Engineer and AHJ. I hope your quote included a provision so you get extra $$ if the pipe sizes increase due to the hydraulics. At 02:10 AM 1/12/2011, you wrote: >I am bidding on removal and replacement of an >existing dry pipe system. This is about 1,000 >feet of 3 inch. Part of the specification is >“Contractor shall submit working plans that >have been approved by authorities having >jurisdiction, including hydraulic calculations, >prior to starting work.†Is it normal to have >new calculations done when just replacing >rusting pipes? If so, where do you draw the >line at needing new calculations? There has >been new construction, since the building was >built. Three new low hazard buildings have been >built, with a new low hazard rehabilitation >facility going in a block down the >street. >_______________________________________________ >Sprinklerforum mailing list >[email protected] >http://fireball.firesprinkler.org/mailman/listinfo/sprinklerforum >For Technical Assistance, send an email to: >[email protected] To Unsubscribe, send >an email >to:[email protected] (Put >the word unsubscribe in the subject field) Todd G. Williams, PE Fire Protection Design/Consulting Stonington, CT 860.535.2080 www.fpdc.com _______________________________________________ Sprinklerforum mailing list [email protected] http://fireball.firesprinkler.org/mailman/listinfo/sprinklerforum For Technical Assistance, send an email to: [email protected] To Unsubscribe, send an email to:[email protected] (Put the word unsubscribe in the subject field) _______________________________________________ Sprinklerforum mailing list [email protected] http://fireball.firesprinkler.org/mailman/listinfo/sprinklerforum For Technical Assistance, send an email to: [email protected] To Unsubscribe, send an email to:[email protected] (Put the word unsubscribe in the subject field)
