Recent updates to our Underwriter Laboratories (UL) listings for exposed basements are likely a welcome change for contractors who work on NFPA 13D systems.
Before the update, listings required system mains to run perpendicular to the joists; branch lines had to run parallel to the joists. With the updates to the listings for unfinished basements,BlazeMaster CPVC system mains and branch lines can be installed perpendicular and/or parallel to the joists.You just need to follow the proper procedures in the manufacturer’s installation guide. Here’s a quick rundown:
If the system mains are installed below the joists, use listed support devices for CPVC piping or other listed support devices that mount the piping directly to the bottom of the joists. For system mains and branch lines installed through the joists, the support holes
must be below the center of the depth of the joist. The holes should be oversized to allow for movement and located to not impair the structural integrity of the joists.
System mains and branch lines must be installed in the cavity below the bottom of the ceiling and above the bottom of the joist. The pipe and fittings must be located at or below the center of the joist’s depth.
Install the pipe using listed support devices for CPVC piping or other listed support devices which mount the piping directly to nominal 2-inch wood blocking. You can also use listed support devices for thermoplastic sprinkler piping that offset the pipe a nominal distance of 1 1/2 inches from the joists.
More Updates on Exposed Installations
Other important changes when installing BlazeMaster CPVC in unfinished basements:
BlazeMaster CPVC is now approved for use with 16-inch joists. We’re the first CPVC fire sprinkler system approved for this application.
The blocking requirement is expanded to 40 feet.
The 1,000-square-foot protected area requirement was removed.
The asymmetrical head layout is no longer required.
These updates should be good news for contractors, who now have more flexibility for installing BlazeMaster CPVC. It’s a good example of how we are constantly working to broaden use of BlazeMaster CPVC while streamlining installation requirements. As always, please contact us with questions.