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13d attic sprinklers

13d attic sprinklers

13d attic sprinklers

(OP)
What are some of your thoughts on uprights in attics in 13d systems?

Some AHJ's are requiring these heads along with patio heads in some situations like limited fire truck access "hillside lots etc."

I think it is dangerous to ask a sprinkler system to do what it wasn't designed to do as there is no science involved in this installation.

We all know a 13d system will buy time to escape a fire, but could it really control a fire in an attic with CPVC piping? Wouldn't you lose your pendant density if even 1 or 2 attic heads activated?


 

RE: 13d attic sprinklers

I have had the same questions with those systems for years, but the AHJ you are referring (assuming I know who it is since you are in AZ) does not bend.  NFPA 13D was never to be a property protection system, but some AHJs take it on themselves to amend standards to meet whatever they think it should be.  However, in that particular jurisdiction, there is a very long history of life safety and property protection in homes protected per their requirements.

And, to answer your question, you could very well lose your pendent density if heads in the attic activated.  It is not guaranteed, but probable.

Good luck working in AZ.  It can be the "wild west" in some areas.  But, overall, the AHJs are good to work with and will assist you in many ways where it is possible.

Travis Mack
MFP Design, LLC
www.mfpdesign.com
 

RE: 13d attic sprinklers

Install and design the attic system to nfpa 13

What is the problem with that???

Normaly there will be two risers

RE: 13d attic sprinklers

The problem is the increased water demand, pressures, etc.  Also, not sure if you can design certain areas to NFPA 13 and others to NFPA 13D in the same home??  But, this AHJ just wants a 2 head calc in the attic as well, if I recall correctly, from the last one I did there.  They also want you to use CPVC pipe with standard spray sprinklers in the attic.  I don't believe this is consistent with the listing of the pipe.  However, based on the track record in that particular jurisdiction, it does seem to be working.  I don't know if studies have been done on the number of fires controlled by the attic sprinklers vs ceiling sprinklers in this jurisdiction.

Travis Mack
MFP Design, LLC
www.mfpdesign.com
 

RE: 13d attic sprinklers

sorry I missed that bus

have not seen a 13"D" system with heads in the attic

got my d's and r's mixed up

that would be interesting. along with do not think the plastic is listed for use as attic protection, would have to check the listing


yea putting your name on something not tested, even as an ahj seems to be taking a big leap


have they had any attic fires??? and if so waht is the track record??? as far as control or extinguishment of the fire??  

RE: 13d attic sprinklers

To my knowledge BM/CPVC is listed for combustible attics with specific Tyco heads but not for this particular situation or application.  This jurisdiction referenced is going beyond the scope of 13D.  

"Fire suppression is a failure in prevention"

RE: 13d attic sprinklers

Yes, BM/CPVC is not listed for the application.  I remember sitting in a meeting with other contractors and the AHJ when these requirements came out.  Several of asked asked why they felt they could require something that was not per a manufacturer's listing.  I still to this day remember the quote: "We have seen it in several places in California and that is how they do it and this is what we want."  We brought up the issues of liability and such should the system fail because of unlisted material.  Again, it was the same thing - "This is what we want and what we will require."  

Again, this jurisdiction has a long history of residential fire sprinklers and is well known for their report on the history of residential fire sprinklers since it was made mandatory in their jurisdiction many years ago.  I don't know what the rate of fires in the attic has been shown to be.  But, they do have a nice record of what residential sprinklers can do.  However, you have to remember that the requirements in that jurisdiction are above and beyond NFPA 13D in a few areas.  As such, one should not necessarily point this jurisdiction when looking to the effectiveness of 13D.

Travis Mack
MFP Design, LLC
www.mfpdesign.com
 

RE: 13d attic sprinklers

Are they requiring the whole attic to be sprinkled or just a few heads at the ridge and/or a head or two located at any furnaces in the attic?

RE: 13d attic sprinklers

It varies on the jurisdiction.  The first one to incorporate all of this just wants a "pilot" line at the attic ridge.  Others in the area want the full attic provided with sprinklers.

Travis Mack
MFP Design, LLC
www.mfpdesign.com
 

RE: 13d attic sprinklers


Just so we are clear, we are talking about Scottsdale Arizona, I take it?  Can't argue with their track record, that is something to be proud of.

RE: 13d attic sprinklers

Scottsdale is one of the jurisdictions that requires sprinklers in homes in AZ.  But, the track record of NFPA 13D can't necessarily be correlated to the Scottsdale successes as Scottsdale requires a modified 13D system.

I think they have a relatively good thing in place - minus the CPVC in the attic with standard spray pilot heads at the ridge.

Travis Mack
MFP Design, LLC
www.mfpdesign.com
 

RE: 13d attic sprinklers


I was told at the SFPE conference that a new trend in home structure fires is when a fire on the back porch spreads into the attic.  A by the book 13D would not protect against that.

Interesting topic.  I guess from an AHJ's perspective, this is a story of, "two heads are better than none" lol
  

RE: 13d attic sprinklers

But, is 13D really designed to protect against that?  I was taught that a 13D system is designed to basically buy you 10 minutes to get everyone out of the house.  If it burns, it burns.  The system is to sound an alarm and buy you time to get out.  We often forget that fire sprinklers are really good at doing more than what they are intended to do.

Travis Mack
MFP Design, LLC
www.mfpdesign.com
 

RE: 13d attic sprinklers

(OP)
I think Scottsdale no longer requires these attic or patio heads, but some surrounding cities adopted similar codes, the problem we had with these codes is that we had trouble with the definition of an "attic" and "patio" Some houses had TJI construction w/ dropped ceilings and soffits below TJIs and the insp. wanted heads in these. Scottsdale originally wanted heads on the ridge only spaced @ 15' and sprigs w/ non combustible insulation, but houses w/ flat roofs required heads @ 225 SF. You could imagine having to put sprinklers on a patio of a 20 million dollar home w/beams w/ tongue and groove on top of beams and block exterior walls, no option for sidewalls, some had 2" exposed copper pipe "for freeze protection". I think there was confusion as to what these heads were intended to do, alert us of a fire, or put out a fire or both?   

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