Flex Head Attachments
Sprinkler systems have seen an increase in the use of specifically listed equipment. Flexible arm-overs serve a great purpose in sprinkler system installation but are heavily depended on proper installation per the manufacture listing requirements.
If you look at the first picture above you may say “Well it truly depends!” So lets make a couple of assumptions:
- The system was properly designed to account for the friction loss of the devices
- The flex head is listed for use on sprinkler systems
So the question is, does this meet code…. oh and take a look at these pictures below
View of the flexible piping
So Mrs (or Mr.) Inspector, does this meet code? How do you cite this if it is a violation? Does it matter if your referenced version of NFPA 13 does not specifically address flexible arm-overs?
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{ 5 comments… read them below or add one }
No – improper installation –
Minimum Bend Radius:
• 7″/178 mm (FM Approval for braided system)
• 4″/102 mm for (UL Listing for unbraided system)
• Do not bend within 2 1/2″ from connection nut.
ALSO< equipment or appliances are required to be installed in accordance with the listing of the device per manufacture's installation guide……
This installation does not appear to meet those guidelines.
It does not appear to meet the manufacturer’s installation instructions of any flexhead sprinklers I’ve seen, because of the tight turn radius. In order to determine if it meets code or not, I would neet to see the manufacturer’s instructions and cut sheet, and the system design criteria. If it does not conform to those things, I would cite is as either not installed in accordance with its listing, or not in accordance with the approved construction documents – depending on which is violated. If the currently adopted issue of NFPA13 does not specifically address flex-head technology, then I believed the “new methods and materials” section would apply.
I’ve inspected several of these systems and in my humble opinion where they go wrong is exactly in this type of installation. When the Tee comes off in a horizontal direction that should tell you something. Each manufacturer has a spec sheet about the number of bends in the pipe allowed for it to still meet your code . We had a manufacturers Rep in to show all our inspectors in the area what to look for in “their product” and they at the time were the only american made product and they taught us to use a small coffee can on a stick/pole. If you cannot fit the can in the bend it is too sharp and the had a specific number of bends I believe it was 6 on a 36″ model. According to our manufacturer a bend is counted in the beginning, middle, and end of the bend that that would make (3) bends. This photo makes a clear indication that the bend it not correct and would restrict flow thereby messing with your hydraulics. Secondly if you’re not using the right code it very might well come down to a CBO making the decision to allow the flexible sprinkler parts or not.
Dale
I will begin having contractors have the manufacturers cut sheet available at the time of a rough inspection to be sure the installation does not exceed the maximum radius bends. Additionally, on a retro-fit commercial installation, light weight ceiling grids cannot be used. Be sure to review the new calculations, since the length of the flex drop can be much different than regular pipe.