folding partition support

[RacingAZ]

I have this project where we are putting in a new folding partition at an existing 2nd floor (steel joists, steel deck & concrete). The folding partition mfr. stated that they don't need input from structural as their system is specifically designed for that reason.

It is a system where they have their own proprietary truss beam at the top (with diagonal bracings) to support the partition then a post at each end to simply bear at the elevated floor. I was told that they would provide all the attachments above and below the existing floor. I also been told not to worry about the post reaction to the floor slab (no need to reinforce the existing slab) as their system is rated for a max. of 4000 lbs. at each post for a 3 1/2" thk. min. slab.

I'm very skeptical and find this claim hard to believe so I asked for supporting calcs. I was told that providing engineering for this specific request would cost an additional charge per the signed contract.

So I did some quick calcs based off the allowable capacity of the deck slab and it would take at least an 8’ wide strip of slab to safely spread out the post reaction. Then there is punching shear and the issue with the joists taking that additional load. The weight of the partition has to go somewhere.

I don't think that is reasonable. Anyone here dealt with this type of partition system?

 

[msquared48]

Yes, and we always checked out the loading to the structural system. If your framing is supporting the partition, you have a right and a responsibility to get the information you need to do your due dilligence and satisfy your concerns.

Mike McCann
MMC Engineering
Motto: KISS
Motivation: Don't ask

 

[a2mfk]

I'd want to see their technical specs and calcs if they have any. I've never heard of a specialty supplier of partitions or similar making any such claims outside of their own system. I would say they probably intend to certify their post and possibly the attachment are good for 4000lbs. Further, that the bolts they have specified in tension are good for a given embedment and a given slab thickness. This last part seems like a stretch for most pre-fab systems, as they don't want this liability and almost always specifically note this must be evaluated by an engineer.

There is obviously no way they can actually certify IN GENERAL that the floor slab or any structural system is OK for that point load without doing what you did and review the actual in situ condition.

What is your role in this, the EOR? You need to talk to you client and call BS on this.

 

[JAE]

There is obviously no way they can actually certify IN GENERAL that the floor slab or any structural system is OK for that point load without doing what you did and review the actual in situ condition.What is your role in this, the EOR? You need to talk to you client and call BS on this.

Yes...agree 100% with a2mfk.

 

[RacingAZ]

I was brought in to look at their claim. The mfr. said they can go 40' long X 10' high with a 10 psf wall weight (4000 lbs. max. stacked at one end) and their system would work as long as there is a minimum of 3.5" thick of slab to support the posts. No need for additional support.

Pretty much what I'm thinking and I posted this here to get some thoughts. My plan is to recommend putting additional support structure below the slab and check the existing joists (at least add some web angles if the reaction load from the post will be away from the joist panel point).

 

[hokie66]

Maybe their statement about the slab was intended for a slab on the ground.

 

[RacingAZ]

hokie, that was my 1st impression also but verified it to apply for elevated slab.

I think we're all in agreement here that the mfr. claim is some kind of false advertising.

 

[msquared48]

If they keep on doing this, the company will fold like its partitions. It's only a matter of time.

Mike McCann
MMC Engineering
Motto: KISS
Motivation: Don't ask

 

[hawkaz]

I have seen some claims like this. The product manufacturer did a punching shear check only to determine minimum concrete thickness.

Obviously, this isn't a complete picture and their claims are premature.