Fire Sprinkler code NFPA 13D

[inphx]

My new build is in a city that rrequires sprinklers for any new structure. NFPA 13D residential applies to my accessory building which is a clear span steel building.

Question:

Vendor A: tells me for $$$$ he will draft the plans i need now, and the design will be plastic pipes so cheaper later

Vendor B: tells me For $ plus $$ he will bid the entire job installed... and you cant use plastic, need to be steel or copper, because it is against code to use the hangars and exposed piping.


Anyone in the trade want to weigh in on that detail?

If i work with vendor B (am inclined to) i would be a 1/3 into total price if i just paid Vendor A what they want for plans.

 

[DonnyT]

NO plastic!!! NO Copper. Use steel pipe. Will the pipe be exposed to the weather ?? What type of system ?? You may even have to use galvanized pipe. The price was roughly 100 a sprinkler head.

 

[the king crew]

In my town they allow plastic pipe in unexposed residential attics but anything that is exposed needs to be steel. All of it has to be installed by a licensed professional.

 

[StevePgh]

If the pipes will not be covered, then vendor B is correct, you need to use steel or copper. Lay-in ceiling tiles appear to be OK to cover CPVC or PEX pipe, so that remains an option if you are doing a ceiling.

There is lots of information here (pmengineer.com) and a manufacturer information sheet on using PEX for this purpose here (wattswater.com)

Seems like lots of the options are possible or not possible based on exactly what classification your structure is. The wattswater seems like an interesting guide to using Pex with lots of layout and connector info. Points highlighted from the pmengineer article:

Black steel or Galvanized, ASTM A53, ASTM A135 and ASTM A795. 1" minimum. The thinner walls need welded by a certified welder. Thicker walled pipe can be threaded. Lots of conditions based on pipe thickness and certification.

Copper tubing can be either Type K, L or M. The type indicates the wall thickness, with Type M being the lightest wall and Type K being the heaviest wall thickness. 3/4" minimum, brazed, not soldered.

CPVC is a limited combustible piping material; therefore, it must be installed to prevent the pipe from failing during a fire. One of the options is to protect the pipe with a layer of gypsum wallboard or plywood. 3/4" minimum.

PEX tubing must be protected from fire similarly to CPVC pipe. The tubing cannot be exposed and must have a layer of gypsum wallboard, plywood or lay-in ceiling tiles protecting the tubing. Also, you can go with 1/2" if it is a looped system.

 

[kbs2244]

In my experience sprinkler install co.s are a specialty of their own.
Mostly because of the liability concerns and insurance costs.
Check into your guys background.

 

[Stuart in MN]

You should mention where you live, besides NFPA there may be local codes or practices that come into affect as well.

 

[Higgins]

I'd suggest talking to your insurance company and see if they have any preferences

 

[jpinca]

I'm just finishing up the supply and riser side of my 13D system. The sprinkler vendor will handle the heads and piping.

I'm using Uponor PEX, but as said before, it must be protected by drywall or plywood. If you'll use exposed piping, then I think threaded galvanized steel is the way to go.

NFPA 13/13R/13D has all the design information you need to common materials (copper/steel/CPVC). You can view those standards online for free. You should be able to assemble a true materials cost list pretty easily, then compare the vendors quote.

 

[inphx]

Wow - thank you all for your advice.

Btw - i am in phoenix az building in scottsdale

 

[NOZZLEMAN]

Call the Scottsdale Fire Marshal or the building department guy that will be doing the inspection. That part of AZ has some unique fire sprinkler codes.

 

[colbiwon]

Blazemaster CPVC piping is now listed for exposed use in residential and light hazard occupancies. This is relatively new it didn't used to be. It could be that the second contractor isn't aware of that. Here is the listing information: http://www.azfma.com/files/blazeng.pdf

NFPA 13D is not written for this type of building, but the fire marshal is allowing it because they want to require a sprinkler system, but to require an NFPA 13 system would be an unreasonable cost burden for the home owner.

I have seen other jurisdictions do this near me.

There is no reason not to have the cpvc system put in. I don't know if freezing in your area is a concern. If it is you will have to keep the building heated no matter what type of pipe you use. You could also install an antifreeze system, but I would not recommend it. I feel that it requires too much maintenance for a homeowner.