I have a problem with the simplified definition floated out here that a grid system is one that feeds a sprinkler from two directions because of the illustration of a looped system in the annex of '13 which shows sprinklers attached to the end portion of the loop resulting in those sprinklers receiving water from two directions. Technically the only cross main is the center piping - everything else are looped branchlines. I would be prepared for kickback from a knowledgeable AHJ. I would personally avoid a design like this if at all possible to avoid the headache of hashing it out w/ an AHJ. But if it's the difference between a system like this and a fire pump it might be worth the fight.
JH On Wed, Oct 27, 2021 at 6:04 AM Sean Conlin via Sprinklerforum < [email protected]> wrote: > If you were to put caps on the left and right lines going north and south, > it resembles a compound gridded system and a sprinkler can receive water > from both sides. > > The east and west lines are essentially the mains and so is the 4" in the > middle. > > Yes is has a looped piping arrangement and is symmetrical but it is a > gridded system by NFPA-13 definition. If you were to not tie the lines > together, it would be a loop. > > Regards, > > Sean W. Conlin > E:[email protected] > > This message, including any attachments is considered confidential and for > use only by the intended recipient(s). > Any other distribution, copying or disclosure is strictly prohibited. > Please delete this communication and notify > Demand Sprinkler Design Inc. if you are not the intended recipient or have > received this message in error. Demand > Sprinkler Design Inc. accepts no responsibility or liability for any loss > or damage from use, including damage from viruses. > > -----Original Message----- > From: Ed Kramer <[email protected]> > Sent: October 26, 2021 1:31 PM > To: [email protected] > Subject: Gridded dry system > > Is this sprinkler system a gridded system? I've avoided this type of > design in the past for dry systems because it 'kinda' a grid, but not > really. Now I'm questioning my questioning. What are your thoughts? > > > > Reference NFPA 13 (2019) sections 8.2.3.10 and 3.3.206.5. > > > > https://www.dropbox.com/s/u2hw3cbvlga4fcq/Dry%20Attic%20System.pdf?dl=0 > > > > > > Ed Kramer > > > > > _______________________________________________ > 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
