Fixing old problems

I just gutted one of my upstairs bedrooms and now have the chance to do things correctly.
Since my house is 40 years old, there is one 20 amp circuit powering all 3 bedrooms and some outside and hall lights as well. Given our new inventions called computers, stereos, etc., this is not the best model.

I want to run a new 20 amp circuit just for this one bedroom, and disconnect it from the rest of the circuit, without messing up anything existing.

Is there a rule of thumb for looking at existing wiring and plotting the best course of attack? I am more than a beginner with wiring and have done many ceiling fans, outlets, switches, etc., but the simplier the explanation, the better...thanks..

 

The best course of attack is to start from scratch. Wire the new circuit as if nothing existed. You can either leave in place, but cease to use, the existing outlets, or you might be able to rip the wiring out if you can do so without burying any splices. Remove or replace all the old wiring that you can see while you have the chance.

 

Thanks for the quick reply...

If I want to use the outlets in the places they are in, but also keep the original wiring in place like you mentioned, and add new wiring as if it didn't exist, wouldn't I have to switch from single gang to double gang boxes to allow enough room for the "old" wiring and the new improved wiring?

Can I drill through the studs when running the new wire, or do I have to go up to the attic, across, and then down to each one?

 

Let's say you want to abandon all the old outlets. So the current wire is merely passing through this room. Since the walls are open, it should be easy to see where it enters the room and where it leaves it. Remove all the cabling between these two points, and run new cable from the point where it enters to the point where it leaves. As I mentioned earlier, don't bury any splices, so you may need to put your splices in the first and last boxes (unless you can actually work backwards and forwards to the next box out of the room). Replace the existing boxes with 22.5 cubic inch boxes and you should have room.