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Residential Sprinkler Installation

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NJ1

Mechanical
Feb 9, 2010
381
I just won a bid for a new installation on a residential home. What caught my attention is the fact that it is a stand alone three family house but the mechanical engineer (PE) design the system
(not hired by me) as a NFPA 13-2002. I noticed all calculations and notes on the drawings are per NFPA 13 plus he added hose valves at the 3 landings (bsmt, first and second).
Anything wrong with this picture? I think I need this reviewed by a second PE before submitting anything. Right!
 
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I would get a hold of the architect and find out if there was a reason the building was classified as a 13 building and not 13R. Check the building height vs the IBC code to see if a standpipe is required, but with it being only 3 stories it would be very doubtful. Also, check into any other local codes that may superceed that.

Given it's only a 3 family building this would be really odd that it would be a full 13 building, but stranger things have happened and there may be more behind this.
 
It should not matter but how many sq ft


Besides the standpipe are they sprinkling every enclosure and the attic???
 
Keep in mind that 13D's scope is one and two family dwellings, and anything beyond that would be 13R or 13. The AHJ may have their own ordinance like we do that only recognizes 13D and full 13 systems.
 
I understand that but here is the scenario.
It is an existing home where they converted the basement into an apartment.
Now we have basement apt, first floor apt and second floor apt.

This PE.,PhD is an idiot. I do not care what planet we live in but this system should have never be installed with hose valves, Siamese connections and NFPA 13 requirements. I do not want to hear it.
This goes back to past postings of Engineers undertaking work they are not qualified for.

I had the drawings revised by others and they said the same. I figure I get some feedback here.
Thanks anyways
 
If its a single family dwelling just design it to NFPA 13D or IRC P2904, eliminate the standpipe and be done with your efforts.
 
Sorry, I read a little deeper. First, I see a NFPA 13R design. Second, if the building height is less than 30 feet, a standpipe system is not required by the IBC or IFC.

I apologize for the premature interpretation.
 
Stookeyfpe

Thanks so much. I understand your comment but this local fire official wants to see what is the drawing. I just think the engineer made a big pooopooo
 
Oh more looks like an apartment then a sfr

What do you mean the

Fire official wants to see is the drawing???
 

Sounds another mechanical engineer who needs to be reported for practicing outside the area of competence.. If you refrain, then don't complain!

I could report about 3 a week but I review designs for federal property, and the states have no jurisdiction.

Maybe he fully sprinklered it to meet 13 and added standpipe above and beyond building codes. Nothing illegal about that if it meets 14..

Real world knowledge doesn't fall out of the sky on a parachute, but rather is gained in small increments during moments of panic or curiosity.
 
"Sounds another mechanical engineer who needs to be reported for practicing outside the area of competence.. If you refrain, then don't complain!"

In the real world from my end you can't complain because you are in business and you got to deal with what you have. Go after someone and when word gets around you'll be untouchable.

Oftentimes specs read "Do it exactly my way unless it is wrong then it becomes your problem to fix at your expense because you are the expert."

Nearly every job and if we started reporting that is all we would do making an enemy of every single one and I don't need any enemies.

How many times we have read specs and wondered "do they really mean this?" leaving us in a huge guessing game. Specs that sometimes reference other jobs in other states.

If we were like other trades we could just put it in wrong then get a lucrative change order to change it but we are not like other trades.

Sometimes knowing to much costs a job. I know one water purveyor that requires FM-CT meters on fire protection, they will without exception, yet a drawing comes in for bid less the meter. How do I bid because if I include it I won't get the job and if I don't then I would worry I'd have to provide and install with the"you are the expert and should have known" phrase.

Engineers that don't know what they are doing are really good at skating away from disasters they caused and for our little company a $9,000 meter with strainer that wasn't figured in costs is a disaster.

Like earthquake sway bracing. It is in more and more specs but do they really mean it or is it there just to cover their rear ends? Where we work we've never had an earthquake that caused damage, most of us (wave) have never dealt with it over 35 years of experience and what to do? Do I bid it and lose the job, because a competitor certainly will not include it, or bid it without taking my chances?

BTW a I would estimate 95% of the jobs, other than federal work, that spec sway bracing it's never put in.

//Rant Off
 
I totally see your predicament SD2.. I backcheck submitted sprinkler shops against engineered sprinkler plans and I sometimes see the sprinkler subs fixing mistakes the engineer made.. I also see them leave in the mistakes, but I am not privy to the fingerpointing that certainly happens when I write up those mistakes. I'm sure it is not pretty and involves the engineer saying "our massive specs require you to put pipe dope only on the outside of threads, and also include the CYA clause that says design and install in accordance with NFPA 13 and governing codes and standards.. " and the sprinkler sub saying "I built the ____ exactly like your drawing shows, and you didn't show ____". Then the engineer says, "in spec __ it says when there is a conflict, the specs govern.. And the specs require NFPA 13 and all other governing codes and standards, which means you were required to put in ___ required by the local code ___."

The best solution to this issue is to review and force quality from the engineer. If the bidding sprinkler sub can't report it due to politics, then it has to start with the AHJ reviewing the engineer's plans.

I don't get to see all our engineered sprinkler plans to fix them, and the other engineers frankly don't have the skill to review them in the very short time they have to review and formally comment on the plumbing, HVAC, Energy Compliance, LEED, and Fire Protection. We get about 6 hours to review all this for the typical 2 to 10 million dollar projects. That can be a set of 75 drawings and two 4" binders filled with specs, design narrative and calcs. in 6 hours.

I know we had this discussion already where someone blasted me for saying an AHJ can very easily miss one line in a hydraulic calc regarding flex hose equivalent length and not comparing it against the vendor cutsheet. I thought they were way off base in disagreeing with that.

Compare that to your experience.. You estimated a 95% failure rate on AHJs enforcing NFPA 13 requirements for seismic bracing, and have experienced a great many cases where the engineer's mistakes were not caught and yet the plans were still approved for the construction permit.

I know there is no easy solution to bad engineers especially when followed up with poor plans review by the AHJ, but I am sympathetic to the situation from your perspectives.. All I can say is if everyone out there put as much effort into learning as we forum regulars do, then none of us would have much left to complain about.



Real world knowledge doesn't fall out of the sky on a parachute, but rather is gained in small increments during moments of panic or curiosity.
 
I started out working for contractors, but now work as a consulting engineer, so I can completely understand the rants about engineers not knowing what they are doing.

When working for a contractor, feedback from installers comes very fast. If you design something that they don't like, you will find out about it very quickly. Consultants live in a different world. If they come up with something that they think is a fantastic idea that turns out to be a complete pain in the butt for the installers, he will likely be blissfully unaware of it. He will never get feedback from the installers.

Consultants really do live in another world. The word 'Right' takes on a whole new meaning being something that doesn't offend the established beliefs and entrenched misconceptions of your colleagues, client and management most of whom have barely set foot out of the office and onto a construction site.
 
Anyway, in defence of consultants, sometimes engineers take on work that they don't have years of experience with. This is because consultants have to compete with other consultants for work and they need to do the work with the staff and skill set that they have - not the staff that they would have in an ideal world.

Engineers do try to cover their back, drawings are supposed to be used for pricing only, not construction. The contractor is supposed to make changes to the drawing because that's in their contract. If something needs to be changed and this costs more money (in materials and labour), then the contractor should be entitled to claim a variation. If it's possible to save money, then this can suit the contract too.

Why worry if an engineer is practicing outside their field of competance - don't you like variations?
 
lol blueshift that was good.

I will do what I have to do as a contractor period. Do it right.
 
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