BIOSMonkey wrote:
More questions:

1) In order to add enough circuits in my breaker box, I may have to double up
some of the breakers. We had a new heat pump system installed and the HVAC guys
stole a lot of space!

I really only have one breaker space left, and 2 more circuits to run (1 20A for
bathroom and 2 15A for bedrooms), BUT some of the other breakers are single and
could potentially be converted to two small breakers. What are the rules
regarding this? I am wondering why some are single and some are double...why
not just make all of them double to leave space?

Your box will indicate somewhere what its max circuit capacity is; this
will probably permit some but not all of the breakers to be doubles.
For example, if the box has 50 slots it may permit 60 circuits, so 10
of the breakers can be doubles. Be aware that you may need to add extra
neutral (and less probably, extra ground) bus bars; unless the panel
says so explicitly, don't try to put more than one neutral wire under
one neutral bus screw. I *think* you can usually double up the ground
wires but I'm not certain. On this topic code says to do only what your
panel's manufacturer says is ok.

2) Does the bathroom circuit have to be dedicated to the GFCI outlet ONLY or can
it also feed the vanity lights?

I've heard the answer to that and I forget it, partly because Canadian
and US codes are different on that question. Search other postings in
this NG and you'll find it.

3) Can NM cable be run diagonally under the joists, or must it follow the inside
of the joist or through holes? (remember I will be doing a drop ceiling)

In general NM should be along the faces of joists and through holes,
never across the undersides of them. At your ceiling-mounted light
fixtures (octagonal boxes or recessed pot lights) you staple the NM to
the nearest joist and then it can run to the box; there should be no
need for armored cable unless your local code requires it (as I'm told
Chicago, NYC and some others do).

You *might* get away with stapling the NM to boards that are fastened
across the undersides of the joists; this is permitted in certain
circumstances where you're sure there will never be drywall on the
joists. I think it's the inspector's call.

I'm wondering how you'd do a dropped drywall ceiling. I guess you'd
have to build a whole framework of joists at the height you wanted it.
Of course you can never have any electrical junction box hidden insde a
drywall ceiling; there are metal access panels you can build into the
ceiling if you have to. If you plan to avoid junction boxes by making
your connections in the pot lights, ie feeding one pot light from
another, be aware that the little boxes on pot lights may be used as
junction boxes only if they're marked as such. Some are, some aren't. I
think it's a matter of how big they are.

Chip C
Toronto