Storefront Sill Bracing 2

[XR250]

I am doing the light gage design on a structure with storefront systems as shown (see attached). As you can see, if I frame up cripple studs under the window, there is nothing to brace my sill track on the left side. Usually, the EOR has specified cantilevered tube steel to brace the sill, but not on this job. I could cantilever up some cripple studs using moment clips at the slab but these are expensive, labor intensive and the stiffness is questionable. I am thinking about just throwing it back in the storefront supplier's lap and having his system provide bracing for the left end of the sill. Thoughts?

 

[sandman21]

Why is it dumb? You don't know the configuration of the room or building. Project constraints happen and unique situations occur that require things that are out of the ordinary but doable solutions. It's not the EOR's responsibility to anticipate that other engineers will not review a set before designing their work.

 

[XR250]

I cannot say it any better than Jayrod already has.

 

[jayrod12]

I will admit that in rare instances there are such constraints. But that shouldn't absolve the EOR from at least bringing the point up that those studs (in this example) may be better suited as 6" or 8" deep. If he is told that is not an option then at least he has done his due diligence.

For example, I am in the middle of a steel stud design where the arch is expecting 3 5/8" studs to span 18.5'. I need them at 6" centres to work, is that at all reasonable, heck no, are they constrained in the room, nope. It was just no one decided to inform them of the standard limitations of steel studs. I'm lucky enough to work in an environment where we get our fair share of delegated and EOR work so I often get the chance to see both sides of the battle. I'd say more often than not, the delegated design is made difficult by poor EOR drawings (created by others).

 

[Teguci]

If the arch is showing 3 5/8" steel studs spanning 20 feet that's dumb

Allowable distributed load = 0.00 k, deflection at allowable load = 3.4 in (L/70) - I used a heavier stud at that.

 

[XR250]

I'd say more often than not, the delegated design is made difficult by poor EOR drawings (created by others).

Yup!

 

[XR250]

So it turns out the window supplier did not bid the job with his sill and door jambs to carry the wind loads without the sill braced by the metal studs. Of course the metal stud supplier bid it the opposite way (both bid it the cheapest option). Now the GC is sorting out who is to pay. Probably the owner if I were to guess.