I have a two part question regarding a sheer wall.
I need to have the detail for how to transfer it over a cantilever.  I
am using 2x12 joists, spaced 1 foot o.c. and am using 2x6 framing for
walls. the cantilever is 3'.
The second part of the question regards how to tie in the sheer wall
between floors (normal, no cantilever)?

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Request for Question Clarification by redhoss-ga on 07 Oct 2006 12:08 PDT

I understand your question and know how to acomplish what you are
trying to do. Also, I have your e-mail address from the previous
question. Now, the only question that remains is how you want the
details. I can submit in CAD, bitmap, or jpeg. Which would you like.

Hello Sinisa, I had assumed that I would have to draw both details.
However, the second part of your question has some very good details
available online. Look at these and let me know if they are what you
are looking for:

http://www.strongtie.com/strongwall/details/SW2.pdf

http://www.strongtie.com/products/strongwall/raised-second.html

Here is another way not using the Strong tie product:

http://www.awc.org/Publications/papers/WDFPLine.pdf#search=%22wood%20shear%20wall%20connecting%20between%20floors%22

What you need to accomplish is to tie the two shear walls together to
resist uplift and shear. The uplift is resisted using the Strongtie
system (or screws and nails) and shear using either screws or nails.

Here are some more details you might find interesting:

http://www.ventura.org/vcrma/build_safe/pdf/b-40.pdf#search=%22wood%20shear%20wall%20details%22

I did not find any online details for the first part of your question.
You mention using blocking and that would be one way. However, I think
the easiest would be to use plywood as a diaphragm. All you need to do
is to tie the cantilevered 2x12 joists together to prevent any lateral
movement. Let me know which you prefer. I was surprised that there
were no details available for the cantilevered situation you describe.

Please use "request clarification" to respond to my answer and the
questions I have asked of you.

Redhoss

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Request for Answer Clarification by lazarusdesign-ga on 07 Oct 2006 15:49 PDT

Thank you for the prompt response.

For the first part, the cantilever, I would like to use plywood as a
diaphragm.  I still need to use blocking at the end of the wall to
support the wall above, but need to see details for the plywood, is
3/4" sufficient, nailing pattern, size of nails, etc..

As for the sheer between floors.  I think that I will stick to basic
sheer walls not using the StrongWall. Typically, the sheer walls I
have seen use 4x studs at the each end of the sheer wall segment with
either HD5A or HD8A hold downs.. I didn't see anything like that in
the sites that you sent, although they were very informative as to
many other aspects.

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Clarification of Answer by redhoss-ga on 08 Oct 2006 07:39 PDT

I agree that the HDA/HD Holdowns are a good choice. I guess that you
probably have all the information you need on these, but just in case
you don't:

http://www.strongtie.com/products/connectors/HDA-HD.html

I think the plywood diaphragm is your best choice also. Here is some
very good information on this subject:

http://www.mcvicker.com/vwall/page035.htm

After studying this page I would say that you should use at least 1/2
inch plywood with 10d box nails on 3 inch centers.

Please look this over and let me know if you need further discussion or details.

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Request for Answer Clarification by lazarusdesign-ga on 12 Oct 2006 21:34 PDT

the blocking diagram is what i was hoping to get from you in terms of
the cantilever..
the size of the blocking, what angles need to be used (A35 etc)  where
they need to be placed.. etc. etc.

should i be using 4x blocking? that is what i saw in one of the
details that an engineer had sent me,
but i lost those details with a hard disk crash.. 

also, is this blocking just at the end of the cantilever.. or do i
need to also do blocking at the midway position? namely approx 1.5 in
from end ?

lastly, as to the overturning forces at the upper sheer wall.. ??
i kind of understand what you are refering to.. but is there any way
for me to send you a basic working model of the house (pdf file or
sketchup file) so that you can ascertain how best to deal with my
situation. I have a very particular situation.

Only one floor is cantilevered, and the 3 foot of cantilever roof
becomes a walking deck for the floor above.  The load of the floors
above and the roof is never carried by the cantilever.  That load is
carried by the caisonss and the grade beams via posts all the way from
the basement level to the roof level..

Please let me know if this makes sense and if you need further
clarification and/or diagrams..
thanks.
sinisa.

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Clarification of Answer by redhoss-ga on 14 Oct 2006 07:40 PDT

With the 2x12 joists spaced 1 foot o.c., I don't see any need for
blocking other than at the end of the cantilever. At the end it would
be good to use two 2x12's to give you a substantial connection for the
posts you describe. I assume you might through bolt these posts to the
2x12's?

don't forget overturning forces at the upper shear wall for the
cantilever condition.  you have them at the non-cantilever too, but at
the catilever they have nowhere to go if you don't design something at
the ends of the wall.

also, even if using a plywood diaphragm, you need the blocking too.

-cab

redhoss has already taken your $50, so i'm not going to get sucked
into this any further, but blocking at interior shear walls is
required.  you should note again the disclaimer at the bottom of the
page, ?not intended to substitute for informed ? professional advice?.
 that applies to comments and to answers.

-cab