I'll play devil's advocate: It may be allowed up to 24" as indicated in NFPA 13 (2013) Section 6.3.1.1.1* which states " Underground pipe shall be permitted to extend into the building through the slab or wall not more than 24 in. (0.6 m)." The annex for this section states "Extending the underground pipe into a building provides working room to transition to the appropriate aboveground piping. Environmental conditions should be considered as outlined in 24.1.6.1.2." Section 24.1.6.1.2 states, "The transition piece shall be protected against possible damage from corrosive agents, solvent attack, or mechanical damage."
But will the piping withstand fire potential in the riser room? What about the pressure classification of the piping which is highly dependent upon temperature per AWWA C900 per the temperature coefficients in Table 3 (50% reduction in pressure rating at 110°F). Is the correct pressure classification of this piping being used? Is there sufficient restraint at the penetration through the floor slab to withstand the forces of Poisson's Ratio such that the header and riser located above the stub-in and connected to it will not be unintentionally stress-loaded in a way to cause downstream component failure or leakage? AWWA C605 which governs installation of PVC pipe is titled "Underground Installation of PVC..." There is no aboveground installation guide that I am aware of. Will the manufacturer stand behind this installation? Is the piping still UL listed or FM approved when installed this way? The cited article makes no mention of this. Several manufacturers of PVC and HDPE state these piping products are "... Factory Mutual Approved for underground installation only." Acceptable approved 'In-building Riser' fittings are made for this application...specifically with a female end for bell and spigot connections...why not use one of them? 'Working room to transition' as indicated in Section A.6.3.1.1.1 can be accomplished below grade and not under footings by qualified entities wherein the possibility of catastrophic failure for the entire suppression system is mitigated with placing the transition below grade and at the same time non-metallic piping manufacturers' listing limitations are maintained. Ryan L. Hinson, PE*, SET** \ Burns & McDonnell Senior Fire Protection Engineer O 952-656-3662 \ M 320-250-5404 \ F 952-229-2923 [email protected] \ burnsmcd.com 8201 Norman Center Drive, Suite 300 \ Bloomington, MN 55437 *Registered in: MN & TX **NICET IV - Water-Based Systems Layout -----Original Message----- From: Sprinklerforum [mailto:[email protected]] On Behalf Of Richard Carr Sent: Friday, October 02, 2015 11:34 AM To: [email protected] Subject: RE: PVC (C900) for spigot through floor YES, it is allowed. Article in Sprinkler Age by Phill Brown. Richard Carr, SET Branch Manager Cox Fire Protection, Inc 6555 Grace Lane. Jacksonville, Fl. 32205 [email protected] 904-781-8227 -----Original Message----- From: Sprinklerforum [mailto:[email protected]] On Behalf Of [email protected] Sent: Friday, October 02, 2015 12:29 PM To: [email protected] Subject: PVC (C900) for spigot through floor Good morning, Is it permissible to install PVC (C900) as the spigot piece through the floor slab of a building? There would be about 6 to 8" of exposed piping. All I can find in the 2013 edition of 13 is that Fire Resistance of the Pipe shall be considered (10.1.4 (1)). It appears that this wording has been done away with in the 2016 edition and replaced with this, "Where piping installed in a private fire service main must be installed above grade, the piping materials shall conform to NFPA 13". Based on this, it looks to me like using PVC through the floor will be acceptable moving forward. Is this correct? Thanks for the help, Bob Knight, CET III 208-318-3057 www.firebyknight.com _______________________________________________ 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 _______________________________________________ Sprinklerforum mailing list [email protected] http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkler.org
