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Celling obstructions to sprinklers discharge 1

Aikah-Eng

Mechanical
Nov 27, 2021
22
Hi Everyone,

I've a question regarding the obstruction to sprinklers, please check below photo.

I have a retail shop with celling features that obstructing the sprinklers discharge, I aske to remove this annoying things but they said no way!

this can be a ceiling pocket per NFPA 13 - 10.2.9 Ceiling Pockets or what exactly?
I really don't know under which part of NFPA 13 this can be? ceiling pocket or obstruction?

however, I was shocked when I saw it as the drawing was showing a nice flat ceiling only.

Spr_obstruction_nzcv7c.jpg


Thanks for your help in advance.
 
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It is something

Without seeing it on site. A little hard to make a call

Can you place sprinklers around the perimeter, far enough away, to spray under???
 
cdafd,

yes I'm thinking to instruct them to put side wall sprinklers around.

maybe it's the only option there, thanks

 
Are you the engineer of record? I dont see a black and white compliant solution to this. Hard to justify sidewalls... need smooth flat ceiling.

The ceiling pocket allowance might not apply because you're probably exceeding 1000cuft. Protect on the perimeter soffit and ask for a variance. Or ask the AHJ what they would like to see.

 
Aikah

Have you looked at using extended coverage pendants ?
 
Architect has to create a building that can be protected. This space could be protected, but have sprinklers in every pocket of that monstrosity. If they can't drop it 4"-6" so you can apply the 3x rule with SSP sprinklers then they may be looking at sprinklers in every nook and cranny and cause a change order for a pump. I bet the owner and architect could make changes then.

Just a thought.

Travis Mack, SET, RME-G,
MEPCad, Inc
AutoSPRINK | AutoSPRINK FAB | AutoSPRINK RVT

 
I totally agree with Travis.... this is a nightmare from heck!

I wonder why I have never seen something like this?
 

Hey there 😊

Just had to share this with you, I supposed to see a nice flat ceiling as per the drawings, but Once I visited the shop, I found such a compacted one

Told them straight up, They either get rid of these ceiling sheets or bring in sidewall sprinklers around the whole perimeter.

Thanks,
 

Hey there! I didn't actually consider the EC Pendant before, even though I'm familiar with the obstructions and ceiling pocket requirements in NFPA 13. It can be tricky to know when and where to use it. I'll reach out to them to find out if using the EC Pendant will help resolve this issue. Thanks a lot!
 

Thanks for your reply! Every day feels like the Architect is making our lives harder, as if they don't consider how we'll fit our sprinklers in there! To be honest, I'm a bit confused between the 3x role and I-beam role, where each one applies uniquely. Now that you've mentioned it, I'll definitely look into it. I might try using an EC sidewall around this perimeter.
 

I have a feeling that we're going to start seeing more of these intricate ceilings in the coming days. Thank you for your reply. I always trust that I'll receive valuable insights on this forum from seasoned individuals.
 
Thanks for your reply! Every day feels like the Architect is making our lives harder, as if they don't consider how we'll fit our sprinklers in there! To be honest, I'm a bit confused between the 3x role and I-beam role, where each one applies uniquely. Now that you've mentioned it, I'll definitely look into it. I might try using an EC sidewall around this perimeter.

Simple way to think about it. 3x rule is when the sprinkler "could" essentially spray all around. Basically, you need the deflector to be fully above the top of the obstruction. The beam rule is when the top of the obstruction is above the top of the deflector. It is a bit more nuanced than that, but that is essentially how it works.

What is more interesting is that if using standard spray sprinklers, then you can ignore non structural elements in light and ordinary hazard areas where you apply the 3x rule.

Travis Mack, SET, RME-G,
MEPCad, Inc
AutoSPRINK | AutoSPRINK FAB | AutoSPRINK RVT

 

Hi TravisMack, thank you for the useful explanation. I think I understood how to apply it now, especially for the non-structural part.
 

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