Need a book? Engineering books recommendations...

Return to index: [Subject] [Thread] [Date] [Author]

RE: Shear tranfer from roof diaphragm to shearwalls with eaves?

[Subject Prev][Subject Next][Thread Prev][Thread Next]
Or both.  I typically tie the trusses down with a connector for uplift, then
block between the trusses.  You can install the blocking vertical and rip
the top to fit the roof slope OR tilt the blocking so that the 2x side is
flat against the sheathing.  Now you need to attach the blocking to the top
plate.  You can either toe nail or I typically use A35s (I think Simpson is
phasing these out, so I might start specifying LTP4s).  I also show a nail
into the top of the blocking and call out whatever perimeter nail pattern I
am using for the job i.e. 8ds @ 6".

bks

> -----Original Message-----
> From: David L. Fisher [mailto:dfisher(--nospam--at)fpse.com]
> Sent: Wednesday, November 12, 2003 5:16 PM
> To: seaint(--nospam--at)seaint.org
> Subject: RE: Shear tranfer from roof diaphragm to shearwalls with eaves?
>
>
> I agree with Mr. Smith...blocking or Simpson truss connectors.
>
>
>
> David L. Fisher, SE, PE
> Director
> Head of Design and Construction
>
> Cape Cod Grand Cayman Holdings Ltd.
> 75 Fort Street
> Georgetown, Grand Cayman
> British West Indies
>
> -----Original Message-----
> From: Brian K. Smith [mailto:smithegr(--nospam--at)bellsouth.net]
> Sent: Wednesday, November 12, 2003 4:58 PM
> To: seaint(--nospam--at)seaint.org
> Subject: RE: Shear tranfer from roof diaphragm to shearwalls with eaves?
>
> Dan,
>
>         When using pre-eng roof trusses (or even rafters and
> joist for that
> matter), you should still provide a continuous load path to the
> foundation.
> I always use blocking between them.  Your shear load is in the diaphragm,
> and the only way to get it to the top plate is through blocking.  Another
> option is to design your connectors to handle both uplift and lateral
> loading simultaneously.  Are your trusses parallel chord or pitched?
>         As far as the building size, the Building Code is very specific as
> to the
> minimum requirements for lateral support.
>
>
> Brian K. Smith, P.E.
>
> > -----Original Message-----
> > From: Dan Boltz [mailto:dboltz(--nospam--at)mckinleyassoc.com]
> > Sent: Wednesday, November 12, 2003 4:28 PM
> > To: SEAINT
> > Subject: Shear tranfer from roof diaphragm to shearwalls with eaves?
> >
> >
> > When pre-engineered wood roof trusses are shown with a 1'6" eave, is
> > blocking required above the shearwall to transfer the horizontal
> > load out of
> > the roof panels/diaphragm?  The eave currently shown has a non-standard
> > height above the shearwall location so the blocking would have to
> > be cut to
> > the required size.
> >
> > The standard detail I'm referring to is on page 744 of "Design of Wood
> > Structures" by Breyer, 3rd Edition.
> >
> > Also, two of the buildings I'm designing are approximately 40' x 80'
> > rectangular single story buildings.  I'm being told that I
> shouldn't worry
> > about the horizontal shear and that shearwalls aren't required or the
> > blocking I'm referring to above!  Am I missing something here?  I
> > know there
> > is a lot of redundancy in the wall panels, but I was taught to ensure a
> > proper load path from the horizontal diaphragms to the vertical shear
> > elements into the foundation.
> >
> > Thanks.
> >
> >
> > ******* ****** ******* ******** ******* ******* ******* ***
> > *   Read list FAQ at: http://www.seaint.org/list_FAQ.asp
> > *
> > *   This email was sent to you via Structural Engineers
> > *   Association of Southern California (SEAOSC) server. To
> > *   subscribe (no fee) or UnSubscribe, please go to:
> > *
> > *   http://www.seaint.org/sealist1.asp
> > *
> > *   Questions to seaint-ad(--nospam--at)seaint.org. Remember, any email you
> > *   send to the list is public domain and may be re-posted
> > *   without your permission. Make sure you visit our web
> > *   site at: http://www.seaint.org
> > ******* ****** ****** ****** ******* ****** ****** ********
> >
>
>
> ******* ****** ******* ******** ******* ******* ******* ***
> *   Read list FAQ at: http://www.seaint.org/list_FAQ.asp
> *
> *   This email was sent to you via Structural Engineers
> *   Association of Southern California (SEAOSC) server. To
> *   subscribe (no fee) or UnSubscribe, please go to:
> *
> *   http://www.seaint.org/sealist1.asp
> *
> *   Questions to seaint-ad(--nospam--at)seaint.org. Remember, any email you
> *   send to the list is public domain and may be re-posted
> *   without your permission. Make sure you visit our web
> *   site at: http://www.seaint.org
> ******* ****** ****** ****** ******* ****** ****** ********
>
>
> ******* ****** ******* ******** ******* ******* ******* ***
> *   Read list FAQ at: http://www.seaint.org/list_FAQ.asp
> *
> *   This email was sent to you via Structural Engineers
> *   Association of Southern California (SEAOSC) server. To
> *   subscribe (no fee) or UnSubscribe, please go to:
> *
> *   http://www.seaint.org/sealist1.asp
> *
> *   Questions to seaint-ad(--nospam--at)seaint.org. Remember, any email you
> *   send to the list is public domain and may be re-posted
> *   without your permission. Make sure you visit our web
> *   site at: http://www.seaint.org
> ******* ****** ****** ****** ******* ****** ****** ********
>


******* ****** ******* ******** ******* ******* ******* ***
*   Read list FAQ at: http://www.seaint.org/list_FAQ.asp
* 
*   This email was sent to you via Structural Engineers 
*   Association of Southern California (SEAOSC) server. To 
*   subscribe (no fee) or UnSubscribe, please go to:
*
*   http://www.seaint.org/sealist1.asp
*
*   Questions to seaint-ad(--nospam--at)seaint.org. Remember, any email you 
*   send to the list is public domain and may be re-posted 
*   without your permission. Make sure you visit our web 
*   site at: http://www.seaint.org 
******* ****** ****** ****** ******* ****** ****** ********