"Hi, I have seen some remodelers with an existing receptacle that is wired with
12/2 and on 20 amp breaker tap into it with 14/2 wire to add a switch and
new fixture. Is this up to code or is only 12/2 allowed on the 20 amp
breaker? Can this 20 amp breaker be downsized to 15 amp to prevent any
overheating or is no smaller gauge wire allowed on a 20 amp circuit?
Any information on this would be appreciated. Thanks