On 2009-11-09, jamesgangnc wrote:

I'm building a detached garage with 2nd story living space that is
about 14 feet from the house. The two are connected by the deck
that also wraps around the house. Basically you go between the
house and garage via the deck. I powered the garage via a 100amp
breaker on the main box to a subpanel in the garage.

This is an interesting situation and a judgement call: does the deck
connecting the two habitable spaces make the whole thing one
structure? You should ask your local electrical inspector. If it is
one structure, then there is no extra complexity, so let's assume for
discussion they are separate structures.

Given two structures, did you install the required grounding electrode
system at the garage? Did you provide a main disconnect, or arrange
for six or less breakers in the garage subpanel? I assume you used a
4 wire feeder and kept the grounds and neutrals separate.

But I've also installed an outdoor light fixture on the door of the
garage that opens on to the deck. And I extended the 3-way switches
out to a box just inside the door.

See http://forums.mikeholt.com/showthread.php?t=105699 Apparently
225.30(D) of the 2008 NEC allows what you have installed.

I did this by running two pieces of uf, 14/3 and 14/2 out to the
garage inside the deck joists.

Hopefully you stayed 1.25" away from the edge of the deck joists, as
is required when running parallel to the framing members.

I'm curious to ask why you needed to run 14/3 and 14/2 to the garage
3-way switch. 14/3 would have been enough to provide two travelers
and a common; what does the 14/2 provide? If you were to provide
power for any other garage loads from the 14/3 and 14/2 UF, then that
would be a violation of 225.30.

Cheers,
Wayne