I am working on a project which has several buildings with 4-8 apartments each. Between 2 and 3 stories. We are designing 13R systems. There is a 4" main coming into the buildings dedicated to the sprinkler system. The engineer is requiring that the riser consist of the following (after the underground with 4" elbow on top):
4" OS&Y valve 4" pipe a minimum of 10 diameters long (40") 4" RPZ with OS&Y valves on either side (RPZs are now required on all new systems in CT) 4" tee which branches to a 4" check valve and a 2-1/2 x 2-1/2 x 4 FDC At this point, we are "permitted to reduce to 2-1/2" if the calcs allow" 2-1/2" OS&Y 2-1/2" alarm check valve 2-1/2" pipe to the top of the riser Here we reduce to 1-1/4" CPVC to feed the system. The reason the engineer gave for requiring the 4" RPZ and FDC is that the fire department requires a 4" connection to be able to fill their trucks from the FDC. He is now confirming this requirement with the local fire marshal. The specification also called for a 13 system with K8.0 extended coverage commercial sprinklers in all areas, including closets and bathrooms. However, the exclusion from 13R for sprinklers in attics and crawl spaces was directly quoted in the spec. The saga continues......... 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)
