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Ceiling Joists to Wall Stud Connections through Drywall

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Colleagues:

An architect recently sent me two details showing light gage metal ceiling
joists framing respectively to an existing wood stud wall and a new light
gage metal stud wall.  This is rated construction, with drywall both sides
of the ceiling joists and studs, and the framing is balloon (not
platform) -- with the studs being continuous to the underside of a roof
structure above.  Both details show a continuous track surface mounted on
the face of the drywall and attached to the studs behind it with undefined
fasteners pentrating through the wall board and into the studs.  The client
wanted me to help them specify appropriate fasteners to make these
connections.

I selected appropriate numbers and sizes of wood screws and sheet metal
screws respectively, basing allowable loads on single shear connections, and
gave these to the client, modifying his details to show that the continuous
tracks needed to be mounted directly against the studs (e.g., that the
drywall had to stop above and below the ceiling joists).  He has responded
by saying that he needs to have the gyp board continuous across the face of
the wall (i.e., between the track and the studs) for fire safety and
security reasons, that these kinds of "through drywall" connections are made
all the time, and that I must be missing something if I couldn't calc it out
(I told him that I did not know of an approval that would allow me to rely
on the strength of the wall board and that I did not think it was practical
to design the screws to "cantilever" across the gap that the wall board
represents).

I recently had to help "fix" a similar (but, to be fair, more highly loaded)
connection (which I had declined to approve) for another client after it
failed by tearing of the drywall around the fasteners (a portion of the
drywall was removed and a ledger "ribbon" direct mounted on the faces of the
studs added as a repair), so I am very reluctant to advise this customer to
do anything except cut out the gyp board.

Any suggestions?

Drew A. Norman, S.E.
Drew A. Norman and Associates
Pasadena, California