Shear Wall Cost Efficiency

[cal91]

I'm creating my shear wall standards and would like to hear other's experience on what is most cost efficient.

Obviously 8d nails are cheaper than 10d, 6" spacing cheaper than 4", and regular (whats a better term to distinguish?) panels are cheaper than structural 1, and 15/32" panels are cheaper than 19/32.

It also makes sense to maintain the same nail size and the same panel size.

But what is the more cost efficient... using 8D nails but having to use 4", or 10D at 6" ? What about 8D at 6" w/ structural 1, or 10D at 6" with "regular" sheathing? ETC.

I'm thinking of having my shearwall schedule be...

10d nails on 15/32"

6" en "regular" - 620 plf nominal, seismic
4" en "regular" - 920 plf nominal, seismic
3" en "regular" - 1200 plf nominal, seismic
2" en "regular" - 1540 plf nominal, seismic
2" en "structural 1" - 1740 plf nominal, seismic

Or is the following more cost efficient ...

6" en "regular" - 620 plf nominal, seismic
6" en "structural 1" - 680 plf nominal, seismic
4" en "structural 1" - 1020 plf nominal, seismic
3" en "structural 1" - 1330 plf nominal, seismic
2" en "structural 1" - 1740 plf nominal, seismic

Or would it be more efficient to use 8D insteal of 10D, or 19/32 instead of 15/32, etc.

 

[BridgeSmith]

I don't know about building construction, but in bridge construction, whatever minimizes the labor cost wins.

Rod Smith, P.E., The artist formerly known as HotRod10

 

[jayrod12]

Tends to be the same for buildings. By increasing nail frequency they're having to drive 30% more nails. I don't have the numbers handy, are 10d nails 30% more expensive than 8d? Are contractors even paying attention to any of this when they submit their pricing? I've rarely seem them care that much about nail specifications as long as we minimize the amount of lumber.

 

[KootK]

Are contractors even paying attention to any of this when they submit their pricing?

I would share this concern. I do occasionally get contractors objecting to exotic sheathings but I've yet to hear a complaint about the nailing until the project has begun. Obviously, I do care about the latter when the contractor either is my client or is a position to influence my client.

 

[BridgeSmith]

To expound on my previous statement, the nail spacing (or more precisely, the total number of nails that need to be shot in), and how long that takes, I would think would be the primary component of the cost evaluation. Whatever extra time would be involved to install a shear panel, compared to what would be done otherwise, would be a consideration, also.

Rod Smith, P.E., The artist formerly known as HotRod10

 

[cal91]

Minimizing labor makes sense.

By increasing nail frequency they're having to drive 30% more nails. I don't have the numbers handy, are 10d nails 30% more expensive than 8d?

Instead of comparing percentages, we'd have to compare total costs per nail (or 100 nails.) Especially when labor costs a lot more than material, supporting your first statement.

Ex. 40,000 10D nails vs 60,000 8D nails.

10D nails = 40,000 nails ($40/hour) / (1000 nails/ hour) = $1,600 in labor.
10D nails = 40,000 nails * ($0.02 / nail) = $800 in material
$2,400 total

8D nails = 60,000 nails ($40 / hour) / (1000 nails / hour) = $2,400 in labor
8D nails = 60,000 nails * ($0.01 / nail) = $600 in material
$3,000 total

I've probably already spent way too much time on this. Sounds like 10D, structural 1 sheathing is the way to go. Thanks for everyone's responses.