>On 21/04/2014 10:39 am, "Ed Minch"  wrote:
>
> >1857 - looks like we have a handle on it.  I wonder if the Romans - who
>> standardized so many things - had a similar set of standards.





My father always worked two jobs. He worked at the foundry in skilled trades and
after work he was a electrical contractor. As a boy I was a valuable asset
because I could fit into attics and crawl spaces so I went with him. Since Dad
usually did smaller jobs we would be putting an outlet in a spare bedroom or
adding a porch light in mostly older homes. In Coldwater, MI the houses on
Chicago St. were built in the 1830’s or later.  After a hundred years of changes
and additions the plan of the houses varied with the owners fortunes.  I got to
see the back side of a lot of attic walls and learned how to cut holes in and
patch plaster around outlet boxes and the occasional rat wall.
The lath in the wall depended on what was at hand when the wall was built. Most
was about 5/16” thick and 1 1/4 to 1 1/2” wide. Usually just rough sawn. Most
walls had the lath run horizontally across the room and the length varied so the
joints were staggered across the span. A few were nailed diagonally. Those were
a special pain because the angle left the lath unsupported for a longer length
and chances of the outlet hole breaking out while sawing was much greater. I got
pretty good with a keyhole saw.
Stud spacing was at best random. The studs were native lumber and dried in
place. I think the lath held them square while they were drying but once dry
they gripped the nails so tightly that the nails would break off before they
would pull.
With the native lumber and random placement square corners in the room were the
responsibility of the plasterer. A layer of horsehair reinforced plaster would
be laid up and used to build up low spots with a skim coat of harder plaster
over it. Since the lath was there only to provide a frame for the plaster to be
hung on, stub ends of lath in the corners were common. Fortunately most
homeowners didn’t want outlets in the corners. The hard ones to cut were switch
boxes.
Most people want a light switch near the door entering the room. Door ways
require headers and vary from 29” to 36” wide. That usually meant there was a
stud on one side and a stud and a cripple or short stud on the other side next
to the door, to support the header. In the early 1800’s there were gas lines and
valves installed next to doorways for the gas lights but no one thought of
switch boxes.  With the spacing of the doorway related to esthetics and
convenience more that code restrictions, the cripple usually had stub ends of
lath bridging the gap between the stud and the cripple. It was almost guaranteed
to break the plaster when I cut into it. If there was a cripple it meant there
wasn’t room for a switchbox. We had to chisel an opening in the stud. Native oak
and lath nails meant the chisel had a rough life.
As to stud spacing, most were roughly 16” on center. +- 4”. Unless it was a
corner or someone added a door/window/dumb waiter to the building. In one house
we found a 8’ wide fireplace that had been covered with lathe and plaster. The
owner wanted an outlet in the wall so I chiseled a channel through the brick for
a piece of emt and we put in the outlet.
I’ve lived in 3 houses that were built in the 60’s or newer and they all have
been on 16” centers.
The 4th house was built in 1891 and that was on 16” centers. So it could have
started sometime between 1800 and 1891.