Steel Stud Parapet Height

[dvanee]

Does anyone have a reference for the design of steel stud parapets.

I am looking at the following condition:
- a single story commercial building with a steel structure (20' high).
- exterior wall is a non load bearing steel stud wall with stucco or similar finish.
- studs are located outside of the steel structure and will extend above the roof for the parapet.
- Generally this parapet is in the order of 2-3' so I am not concerned
- along a portion of the building the parapet extends 8' + above the roof (??? How high can I go ???)

For regular strength and deflection design I would assume the cantilever could be equal to 1/2 of the simple span stud capacity (assuming you have adequate anchorage). However I would guess that at some point stability / buckling may become an issue or additional bridging / strapping and a solid connection to the top track may be required to provide stability?

 

[MiketheEngineer]

Typically, angles are added at about 45 degrees from such parapet walls to help matters.

 

[BAretired]

I agree with Mike. An eight foot high parapet should be braced.

BA

 

[ron9876]

Depends on magnitude of loads and strength of studs.

 

[shobroco]

Do you have snow? Angle framing behind a parapet over 4' or so is always done here (Canada) to both brace it & eliminate snow drifting.

 

[msquared48]

Snow is still going to drift with the parapet in place, with or without the braces.

Mike McCann
MMC Engineering

http://mmcengineering.tripod.com

 

[shobroco]

Sorry, I should have clarified: cover the bracing with metal roofing to remove the space from the possibilty for drifting. A 12:12 roof behind the parapet is a great wind deflector and snow eliminator.

 

[wannabeSE]

Sometimes kickers are not an option (ask the architect). Above the roof, lateral torsional buckling may not be an issue because parapets are typically clad on both sides and the cladding braces the studs. Below the roof, bridging or bracing may be needed if the studs are only clad on one side. Web crippling will need to be checked. The openings below the roof need to be considered. If openings are wide with headers high on the wall, the forces on the jambs and headers can be high.

To see if steel studs are practical, you need to do some quick calculations and look at a table with stud moment capacities and I-effective. Also, look at the architectural elevations to see what openings are below the parapets.