My daughter and SIL bought a nice, old, 2-1/2-story home in Davenport, Iowa.
I suspect the floorplan is typical of the era (1920s?). It is basically
square with a full, unfinished basement; two, full, finished floors above
grade; and a third level: the attic. In the attic are 2 or 3 modest dormers
on a four-sided HIP roof.
The previous owners did a LOT of work to this fine place, including the attic.
ago (oak?), the floorboards were subsequently drilled and
insulation was injected. That, of course, will complicate any upgrade to the
rooms room below, but we'd deal with that later.
Right now, the ONLY electrical up there is an old pendant light hanging from
its knob-and-tube wiring controlled by an SP switch at the bottom of the
stairs. That's it. No outlets.
I investigated pulling-up new power from the basement to the attic using the
void that MIGHT exist in the enclosure around the sanitary stack and brick
chimney. Some, if not all, of this space is already occupied by
added/replacement copper water lines to the second floor bathroom that was
remodeled some few years ago. I am doubtful that we'd have much success
adding MORE stuff to this chase. Even if we were successful, it would
probably be tight and even possibly damaging to the cables pulling them up.
I believe it would be "better" to make an EMT run from the basement to the
attic up the outside of the house. This would be close to and parallel to the
main service mast on the rear of the home.
Of course, I want to install a conduit of sufficient capacity to accommodate
all potential future demand from the attic, including the possibility that we
would rewire second floor bedrooms and bathroom below the attic as well as the
demand should the attic be finished, including a window air conditioner (15k
BTU/240VAC). The second floor SEEMS to be adequately cooled by the newer
central air conditioning so capacity up to the attic to accomodate AC window
units in the second floor (below) are NOT a given at this time.
Should I run a 3/4-inch tube or 1-inch?
(Yeah, I know about percentage fill of raceways and boxes but have forgotten
much and am intimidated at the prospect of finding the appropriate reference
for this and making the necessary calculations. I'm asking for a GOOD guess,