depending on your location's building code. I am doing some research recently, some locations use metal pipes, and in this case, it is very easy to replace wires by dragging. You should be able to see those metal pipes in the panel and on any wall outlets. If it is stapled on the stud according to "DangDangDang", then you have no choice but opening all the drywalls.
Are you kidding, old house bedroom/livingroom outlet must be 14 gauge, you can't use more than 110*15= 1650 watt in a certain circuit breaker. You can open your wall outlet to see the wire size. It is printed on the wire, next to AWG www.homedepot.com/webapp/catalog/servlet/ContentView?pn=Wire&storeId=10051& langId=-1&catalogId=10053
【在 a****t 的大作中提到】 : Are you kidding, old house bedroom/livingroom outlet must be 14 gauge, you : can't use more : than 110*15= 1650 watt in a certain circuit breaker. You can open your wall : outlet to see the wire size. It is printed on the wire, next to AWG : www.homedepot.com/webapp/catalog/servlet/ContentView?pn=Wire&storeId=10051& : langId=-1&catalogId=10053