I've been traveling, so apologies for the late reply. Dewayne, you might remind the AHJ that the annex is suggested material and not necessarily a "written-in-stone" mandate or prescription for the design of a system or parts of one. The sketch in A7.3.2(d) illustrates one way of freeze protecting a roof manifold, but there are countless others including the arrangement you describe. The key feature of the A7.3.2(d) sketch is that a firefighter can access the water supply exclusively from the outside of the building; this means that you can pipe to the roof manifold without consideration for access below, such as running in a stairwell. The valve could be concealed or in a chase without leaving some other means of access for operating the valve. If the AHJ is satisfied with alternate means of access to the control valve, there's no compelling reason to use a key valve as shown.
As far as anchoring a PIV - I'd get with the structural engineer. Maybe a letter from him that you can't do it will motivate the AHJ to relax his requirement. Failing that, in my contracting years we always coordinated with the contractor who was building the roof. Show the what you've got and how many actual membrane penetrations you have to make for bolts, the operating stems (or the well for a wrench) and have them come up with a method for water-proofing. That part of it shouldn't be a big deal. Steve Leyton Protection Design & Consulting The foregoing is my opinion only and is not intended to represent the Technical Committee on Standpipe Systems, nor serve as an interpretation of NFPA 14. -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Dewayne Martinez Sent: Friday, December 28, 2007 8:21 AM To: [email protected] Subject: Hose valves at roof top I need to install standpipe hose valves on a roof top per NFPA 14 (07). What I have done in the past is to provide a butterfly valve inside the stairwell to control the roof valves but this particular AHJ is requiring it to be installed per figure A7.3.2(d) with a non-rising stem gate valve in the stairwell and some type of post indicator / capped wrench head on the roof top to open the valve. Any ideas on how to do this without a major leak issue? Also, what is the best way to secure a PIV to a roof deck? Thanks, Dewayne _______________________________________________ Sprinklerforum mailing list [email protected] http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum To Unsubscribe, send an email to:[EMAIL PROTECTED] (Put the word unsubscribe in the subject field) _______________________________________________ Sprinklerforum mailing list [email protected] http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum To Unsubscribe, send an email to:[EMAIL PROTECTED] (Put the word unsubscribe in the subject field)
