When the TC added the requirement for a check valve, in addition to a control valve on every sprinkler connection to a standpipe system, it was in part with the practice of looping in mind. Yes, it's possible that the required signage alerting building service personnel to the presence of another control valve won't be installed or will disappear. But I'm not sure I can otherwise see any compelling issue that would cast this as a bad practice. A potential serious inconvenience, but not a bad practice. As previously alluded to, if the intent of shutdown is for service, the system won't drain if both valves aren't closed. And signage can definitely be made up and made onto systems in such a way that they are not likely to disappear. If our industry would raise its standard of care instead of assuming it's going to get boogered up, this wouldn't be an issue but we're culturally predisposed to assume the very worst.
We have done this often, both for hydraulic benefit and as an alternative means and methods substitution for some heightened code requirement. In low-pressure areas or where a building is particular long or oddly shaped (generally attached residential), we loop where we have to in order to keep CPVC mains at 2" an smaller, as the 2.5" is quite the price pop. Code trade ups include doubling design areas to 8 sprinklers, and looping the mains but calculating only the more demanding dead-end path; this usually to mitigate a not-uncommon practice here in CA to frame with wood but classify construction as a Type III-A "modified". We also deal with projected property lines that figurative cut large buildings into multiple parcels and this is a methodology that is commonly embraced in those situations to enhance the active fire resistance of the subject building. Steve L. -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Eric Tysinger Sent: Wednesday, October 26, 2011 10:46 AM To: [email protected] Subject: RE: Dual floor control assembies I've seen it done quite a few times. In my opinion, not best practice, service nightmare down the road. Yes the signs are required, but once they fall off, is the next inspection company going to know there are (2) valves on the floor and replace the required signage. Thanks, Eric Tysinger CET NICET III - 108988 Designer - Fort Myers Branch Wayne Automatic Fire Sprinklers, Inc. 4683 Laredo Ave. Fort Myers, Florida 33905 p: (239)433-3030 x1240 f: (239)433-3263 C: (239)633-9703 -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Morey, Mike Sent: Wednesday, October 26, 2011 1:32 PM To: [email protected] Subject: RE: Dual floor control assembies I'm not aware of a specific prohibition, and NFPA 13 2010 "6.7.4.3.1* Systems that have more than one control valve that must be closed to work on a system or space shall have a sign referring to existence and location of other valves." would suggest to me it's OK as long as that requirement is met? Mike Morey, SET, CFPS Sprinkler Designer BMW Constructors, Inc. O: 317.651.0596 | C: 317.439.2695 www.bmwc.com -----Original Message----- From: [email protected] on behalf of Ronl.Fletcher Sent: Wed 10/26/2011 1:13 PM To: [email protected] Subject: Dual floor control assembies Is anyone aware of a prohibition against having two floor control assemblies on each floor connected to two different standpipes and calculating the loop to size the sprinkler main? Ron Fletcher Aero Automatic Phoenix, AZ _______________________________________________ Sprinklerforum mailing list [email protected] http://fireball.firesprinkler.org/mailman/listinfo/sprinklerforum -------------- next part -------------- A non-text attachment was scrubbed... Name: winmail.dat Type: application/ms-tnef Size: 3521 bytes Desc: not available URL: <http://fireball.firesprinkler.org/mailman/private/sprinklerforum/attach ments/20111026/7d40f17b/attachment.bin> _______________________________________________ Sprinklerforum mailing list [email protected] http://fireball.firesprinkler.org/mailman/listinfo/sprinklerforum _______________________________________________ Sprinklerforum mailing list [email protected] http://fireball.firesprinkler.org/mailman/listinfo/sprinklerforum _______________________________________________ Sprinklerforum mailing list [email protected] http://fireball.firesprinkler.org/mailman/listinfo/sprinklerforum
