Storage Lockers Facilty/Warehouse - Design Criteria

[mannyman]

Need some input:

We have a warehouse facility providing customers with storage lockers (8' x 10' x 8'H). Size of locker area...+- 85,000 sq.ft.

My concern is that I can't apply CH.13 Misc. storage (NFPA 13) as we are limited to an area of 4000 sq.ft. max. So I have to move on to Ch.14. If folks decide to come and store couches, or plastic bins, books, etc., would I be able to get away with classifying this storage of Class I-IV? or do I have to consider Grp.A plastics stored at < 8'H. This would mean 0.40 over 2000 (with zone reduction). The existing system is pipe schedule with a capacity of 0.25 over 2000 sq.ft.. Hopefully someone can give me some feedback soon. Client expects a quote in the next few days...

 

[cdafd]

So are all the units being protected by heads at the roofline


Or will each unit have head/s

 

[TravisMack]

These things are crazy. If the owner has a solid lease agreement with what is to be permitted, then use that for your guideline. I tend to protect as Grp A because heaven forbid you treat these like OH2 and a design area reduction as well. I have seen that.

Travis Mack
MFP Design, LLC

http://www.mfpdesign.com

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[stookeyfpe]

What's worse is if the owner goes with rack storage and CMDA sprinklers. I've only seen this once and fortunately the site had a decent water supply. My issues were two fold: dry pipe sprinklers (30% design area increase) and the wood containers are built as a solid-flat bottom pallet, which is a 20% increase in the discharge density (see NFPA 13 Section 16.2.1.3.4.7). Owner was not happy with ye AHJ.

 

[mannyman]

It's roof sprinklers and they've built a mezzanine, so 2 levels of sprinklers. Each unit will have a sprinkler yes. Everything is solid pile really. As TravisMack said Grp.A seems like the best protection. But inside scoop is my competitor is not doing a system overhaul. In this case, an overhaul is required since the existing system cannot provide a .40 density. So the customer obviously wants to spend less right...therefor I am stuck between a rock and another damn rock. Tried researching for loop holes but not much in the NFPA 13. I might lose this contract if I can't get the edge. If I'm right in the GRP.A scheme, well, it's the other company taking that chance...unless there is something I don't know. Hence this is where you good folks come in *wink *wink

 

[TravisMack]

One thing I've learned over the last quarter century in this industry - it's better to lose a job for doing it right, than to get a job for doing it wrong.

Travis Mack
MFP Design, LLC

http://www.mfpdesign.com

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[mannyman]

@ TravisMAck: Yep, that's the truth. I second guessed myself is all, wasn't looking to play with fire so to speak. It's frustrating because the other company is an internationally known company, and I just thought, what do they know that I don't. But then again no ones perfect. So hopefully the good guy wins.

 

[cdafd]

Hopefully the ahj will ask questions

 

[LCREP]

Hopefully the insurance carrier has an engineering dept and they review the plans and bounce them back based on the inadequate design. If not when they walk through they will say what??

 

[mannyman]

AHJ or customer will ask questions after they read the explanation in my quotation. It's all I can do. Thanks to all who took the time to respond.

 

[SprinklerDesigner2]

I happen to have one of these right now and we are going with Ordinary Hazard group 2 in accordance with specifications received from the professional engineer of record. His drawings are signed and sealed so whatever happens it isn't my problem.

And I am going to take the area reduction.

If I had to make the determination I would probably go with Ordinary Hazard Group 2 as well because height is limited to 8 feet and to the bottom of the purlins I only have 12 feet off the floor.

I will be watching this thread.

 

[mannyman]

@ sprinklerdesigner2: So in your particular case storage was deemed Class I to IV only?

 

[TravisMack]

The problem with these things is the classifications. Storage may be limited to 8'. But a lot of household goods contain a lot of plastics. It could be piled to 8' of Grp A. That takes you out of OH2.

These things are always crazy. We work closely with the EOR and owner to clarify what they are and are not designed to protect. I honestly hate these projects and turn most of them away because of these issues.

Travis Mack
MFP Design, LLC

http://www.mfpdesign.com

"Follow" us at

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[SprinklerDesigner2]

@mannyman: Yep, the professional engineer of record called it, sealed it and signed it so that is good enough for me.

If it were totally my call I would opt for the Group A plastics just to play on the safe side but in this case that call has already been made and I have learned over the years if a professional engineer calls it you can have a discussion but in the end you give it to them their way with plenty of written material to back you up.

The way these are built the highest any storage can be is 8' with the underside of the steel at about 11'.

Partition walls between the units are 8' high with chain link fence material from the top of the solid metal partition to the underside of the steel.

 

[MGXFP]

Aren't many of these storage type buildings fairly well compartmentalized with multiple layers of gypsum board within each unit?

I will agree there is a large amount of uncertainty with what could be stored within these units. It seems every situation couldn't be accounted for.

Typically we walk away from these because the owner's engineer has classified it as light hazard or something zany like that.