Cutting drywall and drilling from below may be the only option if you have to access the attic there.
Drill top plate in the attic.
If one wants to add a new receptacle on the second floor in a finished room with no receptacles the easiest method appears to be doing the wiring in the attic.
And use semi rigid wiring fish tape to pull your wiring down to your outlet location.
Imo cutting a hole in the sheet rock on the wall and lid and drilling your holes up into the top plate would be the easiest solution.
I ve been reading the irc 2015 and the wording for drilling into top plates isn t clear.
It would nice if the top plate was fastened to the joists above immediately on both sides of the area where all these holes will be drilled.
However this would require one to drill one hole through the top plate in order to get the wire from the desired receptacle location into the attic.
To fix it you just fill the gap with caulk or spray foam.
Normally you would cut out an access hole in the plaster below the top plate and drill a hole through the top plate.
This will also make it easier to fish the wire.
Just go up in the attic pull back the insulation and find the top plates.
Before drilling go into the attic and find the top plate 2x4 that is right above the vent and make sure there are no wires running directly above it that might get cut by the drill.
An alternative is to drop all the way through the wall cavity from another top plate in the attic and into the basement or crawlspace then run over to the wall you want to end up in.
When piping or ductwork is placed in or partly in an exterior wall or interior load bearing wall necessitating cutting drilling or notching of the top plate by more than 50 percent of its width a galvanized metal tie not less than 0 054 inch thick 1 37 mm 16 ga and 1 1 2 inches 38 mm wide shall be fastened across and to the plate at each side of the opening with not less than eight 10d 0 148 inch diameter nails having a minimum length of 1 1 2 inches 38 mm at each side or.
I did this recently to run ethernet cable in an exterior wall.
If you will need to fish wiring through a wall drill a hole through the wood plate in the attic only.
I ve got a 2nd story home theater room under construction.
The photo at left shows a typical one flush drywall on one side and a big gap on the other.
If this is just a partition wall not load bearing and the wall is well supported on both sides of where you want to drill the holes i don t think there is any limit.
The framing has been done but i m going to be doing the wiring myself.
I prefer to stick the drill into the vent and drill up into the attic instead of drilling down from the attic.
