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RE: LGSS - Light Gauge Steel Stud question

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Charlie, you hit it on the head with the foam solution. I received the same
suggestion from Bob Kazanjy and thought this to be a great idea. Here is
only one problem - I found out after offering the suggestion that the
contractor had already packed batt insullation into the beam cavity - nice
thought, but kind of screws up this idea.
The foam is possible, however, in the 12" garage door header since this was
not filled with batt.
I can't really count on the connection of the gypsum or exterior stucco to
resist buckeling of the web to the inside of the wall, but would be willing
to consider the rigidity of the materials as appropriate bracing against
buckeling of the web in the outward direction since these materials are at
least connected by perimeter (at worst) connections of the lath or gypsum.

I still like the insertion of the bolt with spring wing connector to create
a brace at midspan web from buckeling. I would think that I would be safe to
provide one bolt at each end and one in the middle for each header less than
6' wide and spaced at 48" o/c for wider headers. I would suggest that if the
threaded rod is to be sheared off flush to the face of beam that it be tack
welded in position to allow for a clean drywall and stucco patch.

Thanks for the suggestion - amazing how creative minds tend to work in the
same direction of thinking. I never even thought of the foam until Bob
brought it to my attention and then it struck me as such a wonderful and
inexpensive solution to this problem.

Regards

Dennis Wish PE

"Science may have found a cure for most evils; but it has found no remedy
for the worst of them all- the apathy of human beings."
Helen Keller

|-----Original Message-----
|From: CanitzCF [mailto:CanitzCF(--nospam--at)aol.com]
|Sent: Monday, March 16, 1998 8:19 PM
|To: seaoc(--nospam--at)seaoc.org
|Subject: Re: LGSS - Light Gauge Steel Stud question
|
|
|Dennis -
|  This is a tough one. The contractor's suggestion of reinforcing the
inside
|member web will not benefit the outside member web.
|
|  Regarding the 8" deep member, the web h/t ratio is approximately 230
which
|exceeds the AISI mandated limit of 200 for unreinforced webs. I know I'm
going
|out on a limb on this but could the attachment of the gypsum wallboard and
the
|exterior finishes(if sufficiently screwed to the web) be deemed
satisfactory
|to prevent lateral buckling of the web for both the interior and exterior
|members? I realize there is no way to quantify this assumption but perhaps
it
|could fall under the purview of an empirical "enginnering judgement".
|
|  Regarding the 12" deep member, the web h/t ratio is approximately 340.
|Therefore, your proposed solution(short of removing the 20 gauge header and
|installing heavier gauge members) may be the way to proceed. Just a
thought -
|What do you think about installing foam insulation within the cavity
between
|the member webs? This material, once hardened, is fairly stiff and could
|provide resistance to any inward web buckling.
|
|
|Charlie Canitz, PE
|Bel Air, MD
|
|
|