A.Howard Cook, of Bay Area
Retrofit in Berkeley, Calif., responds: Since
the home was built in 1930, it's probably framed
with old-growth, full-dimension, close-grain
Douglas fir lumber, a framing material we've found
practically impossible to split.
You can experiment on a cripple stud by nailing
slightly staggered nails 2 to 3 inches on-center to
see if it splits, but I doubt it will.
If it does, predrilling (typically with a drill
bit sized slightly smaller than the 0.131-inch
diameter of an 8d common nail) is an option, but
it's slow, which is why we prefer to use 15-gauge
electro-galvanized staples when fastening plywood
shear panels onto short, new-growth 2x4 studs or
To meet or exceed APA guidelines for wood
structural panel shear walls (see APA Research
Report 154, Form Q260, available at
www.apawood.org), we use 1 3/4-inch-long staples
with 1 5/32-inch structural I-rated plywood
sheathing, slightly staggering (by about 1 inch)
the staples from the stud's centerline.
Because staples can rust through more quickly
than thicker-diameter nails, we use stainless steel
staples whenever we suspect moisture might be a
While a lot of money has been wasted on fancy
straps and connectors, it's interesting to note
that none of the existing seismic retrofit
guidelines (such as Chapter A3 of the International
Existing Building Code) address the connections
between floor framing support members.
Since even modern building codes address these
connections with only a few toenails, check and
make sure the tops and bottoms of the posts are
nailed so that they cannot be knocked loose.
They're sometimes hard to see because the rusted
nail heads look like the surrounding wood.