huangyhg

parapet bracing for a strip mall
i am designing a strip mall with rather high parapets. the mall is a steel framed building with steel bar joists on steel beams. the roof is a built-up roofing system. the typical parapet height is 5 feet and the parapet at the mall entrance is 10 feet. we need to brace the 10-foot parapet for sure. i haven't checked the 5-foot parapet yet. the parapet and facade is eifs on 6-inch metal studs. we only can work with 6-inch metal studs for facade and parapets. how do you usually brace parapets on the roof? we were thinking to put metal studs at 45 degree angles and put plywood sheathing on top of the studs. the roofing would go over the sheathing to the parapet. i've noticed on some of the big box retailers that the parapet signs are braced with what appears to be steel pipe. i don't know how the connection to the studs and roof joists is made. is there a name for this type of bracing? i thought i read of a name or a proprietary product. so the main question is, how do i brace the parapet?
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however you hose to do it, and the shed roof configuration is good, just re
can you continue the vertical parapet supports down below the roof and then provide a brace on the inside of the building (below roof level).
i have seen a diagonal brace back to the roof below. this was done with pipes, so that the flashing could be done similar to a plumbing vent pipe penetration, but i agree with msquared that penetrations should be avoided when possible.
csd72,
vertical support will have to be taken by a beam or a joist.
msquared48,
what are pitch pockets? the problem i see with the shed roof is that the horizontal leg will have to be 10 feet long. that is a lot of roof space on a 45 degree slope. would you still be concerned with the pipe penetration that is flashed like strguy11 suggests? i'm concerned with this detail. the shed roof detail is easy but the 5-foot and 10-foot sloping roofs at each parapet concerns me also.
both options you present are feasible, although i prefer the shed roof option as well. with the diagonal pipe option, you would need a horizontal girt on the back side of the parapet.
daveatkins
a "pitch pocket" is a sheet-metal or rubber boot, sometimes conical, that goes around a roof penetration such as a vent pipe and gets an elastomeric sealant....
this is what i meant:
csd72,
unfortunately we cannot do that. we have to use another hanger detail to support the facade because the architect is using a ribbon window, actually a 12-foot window all the way around the building. the ceiling height is low. the parapet heights are 5 and 10 feet above the bar joists. we can only use a 6" metal stud, nothing larger. the parapet unfortunately needs to be braced.
jkw05, i have included the snow load already. this is a crazy project driven by a developer and a half-wit architect. we even have to support our foundations on helical piers. and of course we have to use moment frames with the top of steel 16'-6" aff.
vincent,
if there is a developer involved, they are mainly worried about $$.
if you have problems with the architect being difficult, you can often get around it by convincing the developer client that your way is much cheaper (but make sure it actually is).
can you cantilever the studs or provide a tube every so often and make the studs infill?

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