NFPA 13D & Nonresidential Sprinkler Heads

[mattyd723]

In some situations it is better to run exposed steel pipe with upright sprinklers than with pendent sprinklers because the uprights are less susceptible to damage. This has always challenged me because in 15 years of designing sprinkler systems, I have not yet seen or heard of a residential upright sprinkler being manufactured. Furthermore, it seems to me that NFPA 13D (2013) is moving away from allowing the use of quick response spray sprinklers in one- and two-family dwellings (except for mechanical closets, unheated areas, saunas & steam rooms--presumably due to temperature ratings). However, they don't clearly state that it is now illegal to use quick response spray sprinklers (uprights) say, to protect an unfinished 13D basement. The discharge criteria was worded differently in earlier editions, making it sound acceptable to use them, but in 2013 they seem to be moving toward the "...ask the AHJ" cop out. Does anyone have any insight on this issue?

Thanks,

Matt

 

[cdafd]

but in 2013 they seem to be moving toward the "...ask the AHJ" cop out""""""""


do you have a section reference

 

[mattyd723]

8.1.1.1 from the 2010 edition has mysteriously vanished from the 2013 edition's new Chapter 10, causing me to wonder about sprinklers that are not listed with specific discharge criteria. I could ask the AHJ about it, or I could ignore the 2013 edition until they start enforcing it and worry about it then.

 

[cdafd]

check the top two items on page 34

http://www.nfpa.org/Assets/files/AboutTheCodes/13D/13D_ A2012_AUT-RSS_ ROP_Ballot.pdf

 

[mattyd723]

Yes, I see what they are saying in this document. It still evades my issue. While it is true that there are no residential sprinklers listed without specific discharge criteria, quick response spray sprinklers are all listed without specific discharge criteria. I can't find where it says all sprinklers in a 13D system must be residential sprinklers, so it is unclear to me whether or not the intent is to forbid the use of quick response spray uprights in an unfinished 13D basement.

 

[cdafd]

Thought it said that in regular 13. Will have to look again

 

[cdafd]

7.5 Sprinklers.

7.5.1* Listed residential sprinklers shall be used unless another type is permitted by 7.5.3, 7.5.4, or 7.5.5.



7.5.2 Residential sprinklers shall not be used on systems other than wet pipe systems unless specifically listed for use on that particular type of system.



7.5.3 Listed residential or quick-response standard spray dry pendent or dry sidewall sprinklers shall be permitted to be extended into unheated areas not intended for living purposes.



7.5.4 Quick-response sprinklers shall be permitted to be used in mechanical closets.



7.5.5* Quick-response spray sprinklers shall be permitted to be used in saunas and steam rooms in accordance with 7.5.6.3(4).


I think the restrictions of 7.5.3, 7.5.4,7.5.5 answer your question along with 7.5.1

 

[mattyd723]

That doesn't answer my question, it raises more. Those excerpts from the 2013 NFPA 13D are exactly what I was alluding to in my first post. This is still a grey area. "Unheated areas not intended for living purposes", like a garage. Sprinklers aren't required in 13D garages. So whats the point of 7.5.3? To encourage homeowners to install dry sidewalls in their walk-in freezers and loading docks?

According to 13D, I don't need sprinklers in my basement as long as it has a garage door.

There is no hard definition of "mechanical closet" so a 24' x 40' section of unfinished basement with a furnace & water heater in the corner could be called a mechanical closet. Better yet, if we can manage to park a car in there then we'll know for sure that we don't need to sprinkle it per NFPA 13D. So here we are using common sense and consulting the AHJ instead of relying on the standard.

Anyway, if someone could just invent a residential upright sprinkler, I would be satisfied. I can't believe Tyco engineered a whole new residential dry system complete with residential dry pendents and residential dry sidewalls... and yet we still do not have a residential upright.

 

[cdafd]

Does no upright head maybe have something to do with the spray pattern from a residential head??? Plus pipe would need to be exposed, so possibly cvpc could not be used unless listed for exposed use

 

[cdafd]

Unheated Exterior storage room??

 

[skdesigner]

Blaze pipe is listed for exposed installation in unfinished 13D basements subject to certain installation and framing criteria.

http://www.vikinggroupinc.com/literature/TDR-4122

For what it's worth, the manufacturers likely don't make res uprights because there isn't a market for them. I can't imagine testing and listing new sprinklers in this day and age is a cheap endeavour. Sure it would come in handy in some limited situations, but does it make the manufacturer MONEY? Return on investment is what makes things happen.

"In some situations it is better to run exposed steel pipe with upright sprinklers than with pendent sprinklers because the uprights are less susceptible to damage". What happens when the decision is made to finish said basement? The pendants are going to be installed anyways. Seems like better value to the homeowner to install the plastic pipe and pendant sprinklers and all he/she has to do is put up the sheet rock on the bottom of the joists.

Maybe I'm just not seeing the situation right.

cheers

 

[mattyd723]

I tend to think that if I were the only company with a listing on a residential upright, I could make a few dollars off it. You're probably right right though. Money is the reason. Shocking.

 

[concernpro]

The contractor installed 4 sprinkler heads for a branch line of 1 inch diameter pipe (2 pendent heads below ceiling and 2 upright above ceiling). Per NFPA code requires only 2 sprinkler heads for 1 inch dia branch pipe. Contractor designer said 4 heads is acceptable per their hydraulic calculation. Is that acceptable/true?

 

[stookeyfpe]

Con

Start a new thread

 

[majesticphil]

I'm surprised no one brought up section 8.2.5 (I only have 2002ed handy, not sure if its still in the newer editions).

8.2.5 In basements where ceilings are not required for the protection of piping or where metallic pipe is installed, residential sprinklers shall be permitted to be positioned in a manner that anticipates future installation of a finished ceiling.

The provision in 8.2.5 provides guidance when installing sprinklers in unfinished basements. NFPA 13D requires sprinklers in areas where the basement is not finished. If other than nonmetallic pipe is used, the deflectors can be installed as if the ceiling were installed.

So in lay terms it seems to say to me that you just pretend there is a ceiling and get back to designing really that's what it says right? Always brings a smile to my face.

 

[mattyd723]

That's a great point, majesticphil and that's how I try to design basements 99% of the time on 13D projects. However there are those unique situations where someone wants permanent exposed steel pipe and it would be nice to have an upright sprinkler that we could legally use in this scenario. But there isn't, so I have to tell them they must use residential pendents.