The largest section of shelving is 65" wide, 37" tall, and 9" deep. It has
three rows of books (183 linear inches of bookshelf), so almost 300 pounds
for a fully-loaded unit based on my measurements. It's hanging up near the
top of a 9' ceiling, so I don't think it will make a convenient step-stool
for painters...but then again someone reaching to get to that top shelf
could fall off their chair/ladder/pile of phone books and attempt to use a
shelf as a grab bar on the way down.

The mating surfaces of the French cleat will be about 3" below the top of
the unit, as you guessed.

I don't know what gauge the studs are; this is not for my house.

The wall cleat will span five studs, so there's 60lbs (shear) per stud, and
at least two fasteners per stud.

In addition to the French cleat along the top, I was going to fasten a 3"
strip of the same 3/4" plywood along the bottom, and the cases will be
screwed to these through the backs. The upper cleat is what's really meant
to take the load, though.

I suppose I could go with a hybrid approach: put a row of EZ-Toggles along
the top of the main cleat (where the pullout loads are greatest), and put
another row or two of fat sheet metal screws lower down to finish the job.

Thanks,

Chris.

"BobK207" wrote in message
ups.com...
How tall are the shelves? How close to the top edge would the strip be
mounted? How deep (~10")?

So if your studs are 16" o/c that's 32lbs per shelf per stud.

If you're talking about a 4-shelf unit (~40 to 48" high & about 10"
deep). The CG of your book load is about 6" off the wall, the total
(per stud) book load is about 130 lbs.

If the line of action to resist the shelf pulling away from the wall is
~3" from the top & the bottom edge of the shelf bears against the wall
you have a resisting "couple" of about ~36" minimum.

If my way of looking at it makes sense; we've got 6" x (130lbsof books
+ 25 lbs of shelf)

Or (torque yanking bookshelf off the wall) 930 in-lbs resisted by a
36" couple

Need ~25lbs of safe allowable withdrawl per stud location. We also
need 155lbs of safe allowable shear resistance per stud location.

I'm was concerned about shear loading than withdrawl but that's just
my point of view.

I'm talking about burly #12 or #14 SMS not POS drywall screws. Should
be able to get a lot more than 25lbs withdrawl safely out of a #12
unless your studs are paper thin.