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RE: Div. 91

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Mark, if you are speaking of the tension strap connection from the wall to
the roof purlin or sub-purlin, the City of Los Angeles requires a concentric
load path. Therefore, the anchor (an HD for example) needs to be installed
on both sides of the joist or (if you have a wide enough member)you can
install a strap at the top or bottom of the rafter provided you can get the
capacity you need in a connection of this type.
This confused me with the old Division 88 (RGA) methodology that allowed "V"
strap connection. As I understand, this was found to be inadequate unless
placed in every bay. I have not tested my belief, but it would seem
reasonable that if the "V"-strap was placed in each bay, the load to the
rafter would be concentricaly balanced. The last time I wanted to anchor a
rafter to a masonry (reinforced) wall to improve the cross grain tension
problem in the ledger that existed, I offered to do it in accordance with
Div. 91. I was not allowed to use an HD2A attached to one side of the
rafter, but was ordered to install it at each side or to reduce it's
capacity sufficiently to double the required connections at the rest of the
roof.
If Tim McCormick has been checking his digest (since his recent move to the
City of Santa Monica as Chief Building official), he may be able to offer
more information on this.
Dennis Wish PE


-----Original Message-----
From: Mark D. Baker [mailto:shake4bake(--nospam--at)earthlink.net]
Sent: Friday, October 09, 1998 9:20 AM
To: seaint(--nospam--at)seaint.org
Subject: Div. 91


Has anyone used the Zone Four roof to wall connections in the City of
L.A.? If so were single sided installations allowed or were you required
to use double sided connections? Additionally, are there any success or
horror stories regarding the use of this product?

Thanks,

Mark