Attaching Large Signs to Steel Wall Buildings

[klewcm]

Any recomendations for attaching large signs to the wall of corrugated wall steel panel buildings. Interested in simple but safe techniques which will pass muster with passing building codes and wind loads.
Seems as if corrugated panels ( some as thin as 26 ga ) will generally not have the screw holding strength unless the thickness approaches 16 ga or so.
Any thoughts or recomendations ?

 

[MiketheEngineer]

Behind all that steel siding are steels girts that generally run horizontally (some do go vertical) about 24'' - 30'' oc and carry and support the steel. Also there are steel frames that the girts tie to - but they may be anywhere from 10' to 20' or even 30' oc. Plan on attaching to the girts.

But if it is like most steel buildings - there may be very little "extra" for carrying any superimposed loads. So double check them. And girts are really not designed to carry much vertical load - usually just wind.

If the walls can already carry the wind load - how will your sign add any more wind load??

 

[hokie66]

Agree with Mike. Connect to the girts inside the cladding. To carry the load vertically, you may have to provide support for the girts, either propped off the floor or hung from the eaves strut above.

 

[msquared48]

Just plan on reinforcing the girts inside vertically. Uasually they are real wimpy members vertically.

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

 

[paddingtongreen]

You might get away with it if you can connect to the girts near the sag rods, assuming there are sag rods present.

I once put an open web joist in alongside the girt to support the load, using the girt for lateral stability.

Michael.
Timing has a lot to do with the outcome of a rain dance.

 

[klewcm]

Thank You gentlemen.
Girts not anywhere close to customers location for sign. Sign wraps all around perimeter of building. Beams are 20 ft. apart.
Negative wind loads have potential for pulling sign from wall if poorly or improperly attached. Not comfortable with Tek screws or rivets.

 

[MiketheEngineer]

Glue - lots of glue..

Looks like you will have to design some type of supports to be placed probably internally and hung off the frames. Then bolt through. Not going to be cheap.

 

[hokie66]

I fail to understand how with corrugated cladding there would not be girts in the vicinity. Also, I wonder why there are beams in the wall instead of columns. Maybe you need to get a structural engineer involved who speaks our language.

 

[csd72]

Yes you definately need some specific advice from a structural engineer.

1) we have not seen the building (there could be things that you have missed)
2) we dont know the full details regarding the sign.
3) We dontknow the location.
4) we have not carried out any design calculations to verify our design.

Many of these small signs are much more complicated than they look. You may also need a permit for this sign.

 

[Bobber1]

The girts are currently designed for a uniform wind load along their length. A sign will likely need stand-offs at the fasteners so the sign doesn't interfere with the wall corrugations. The stand-offs effectively converts your uniform wind loads to point loads on the girt, a situation it was not designed for.

How 'bout just an independent sign structure just outside of the wall?

 

[lgoarch]

All pre-eng steel buildings will have z-purlins (16ga usually) at 3'6 from top of slab, & at no more than 48" o.c. thereafter with a c-channel over the top of doors/windows (also usually the same ga).
refer to the attached sheet for an example...if the building does not have them already - you just need to place them inside between the W-members (columns) where you need them and attach accordingly with Tek-screws.