Look what I found in NJ

[KZQuixote]

You can't take shear walls all the way down to the ground in a V-zone because the walls need to break away.

Ben,

Are you saying that that's why the straps don't connect the first floor to the second?

Bill

 

[jar546]

Since I am not in a wind zone like that on the coast. I too was curious as to why the straps did not connect the floors. There were no connectors for the rafters either so I was assuming they were not done framing yet. I won't be back there any time soon so be able to check on it.

 

[TimNY]

Simpson has a new connector system using threaded rods to tie the floors together. The upside is they don't interfere with siding and they can be done afterwards; we won't know if they are missing something or if they are just going to do it later.

KZQ brudgers is referring to the pilings when speaking abou shearwalls. In a V zone waves are possible from the storm action. You can't enclose the space permanently as the waves are supposed to pass through the pilings rather than exert lateral pressure on the foundation (as would happen if the walls were solid, such as if shearwalls were continued down to grade)

 

[Architect1281]

My curiosity would begin where the load path ends - all those lovely straps tied into the lateral side of floor joists/truss at first

beams from pier to pier look light? and what holds the second floor to the first and second floor band / floor to first

Hope theres a truckload of timber lok, ridge beam to column to plate and that non continuous stud gable end configuration,

nice hinge effect going there - should I stop

Plywood in shear it might be if they add a second layer to bring the plates............................ I should stop

hopefully lateral and diagonal pier supports.........................I should stop

 

[brudgers]

Ben,Are you saying that that's why the straps don't connect the first floor to the second?

Bill

Not at all.

The structural design of the building is not self evident from the photos - and it may or may not be properly designed.

But in any event, the structural requirements are more sophisticated than your typical SFR.

 

[Mule]

It looks like the straps are part of the portal framing.

 

[Forest]

I wonder if they accounted for Length of nail into stud at strap location minus sheathing.

 

[Mule]

The 2009 IRC allows the straps to be installed on the outside of the sheathing without mention of additional length.

 

[brudgers]

That's because the sheathing is required to be attached to the stud in such a way that the failure will occur in the wood rather than at the fastener. In other words the fastening of the sheathing to the stud is such that they act as a single piece of wood.

 

[Paul Sweet]

The plywood sheathing can be designed and nailed to transfer uplift forces as well as shear forces, so metal strapping isn't always necessary.

 

[TimNY]

Straps on the outside of the sheathing require a 2-1/2" nail per Simpson.

As it was explained to me in simple terms, the sheathing is not used to transmit the uplift forces because it's strength is used for the shear and there's not enough left to use for uplift. Not to say it can't be done, but it would be a significant amount of math and more importantly a lot of drawing to inform the contractor how to properly do it.

 

[brudgers]

There is plenty of strength for both, typically (2300 psi tension for 24/0 rated sheathing).

Straps are used at the discontinuities in the studs typical in platform framing.

At higher windloads, hardware becomes an attractive alternative to additional nailing (e.g. 10d @ 3" o.c. along top and bottom plates.