Yes, it’s possible to rewire a home without removing drywall or, in older homes, plaster. The process involves the same kind of process as using a safety pin to pull a drawstring through the waistband of a pair of sweatpants where it has come out.
First Steps
The Wiring Map
To know where to remove the old wiring, your electrician will make a wiring map. If you have the original blueprints of your home, then it’s easy. If not, then that’s OK, too, because it’s not super-difficult to do in the first place. Basically, the electrician will follow the outlets and light fixtures and then figure out how the wiring goes between them all. As part of making the map, the electrician will plan where to put the new wires at the same time. If you’re upgrading the wiring, such as in a case where you’re also upgrading the junction box, then you might need to reroute the tougher wiring that you need to have installed. Your electrician will go over all of that information with you when planning the rewiring project.
Removing the Old Wires
Most of the time, the reason that you don’t have to remove the drywall or plaster is that the electrician will rewire your home through the attic and/or basement. Sometimes, it’ll be in the crawlspace if you don’t have a basement. After disconnecting the wires from the junction box, in many cases, it’s possible to leave the old wires behind the drywall or plaster because, once disconnected, they’re harmless, and it’s not worth it to tear off the drywall to remove them completely. Some wires, however, will have to be removed for one reason or another. As with the map, your electrician will discuss those places with your and then get your approval to proceed.
The Next Steps
Installing the New Wires
Your electrician will have to disconnect your home’s power to complete the work safely. The installation process includes running wires from the junction box up to the attic or down to the basement and then drilling holes in the right places to be able to thread the new wires to the outlets and permanent fixtures inside your home.
If necessary, or you simply want to have it done, then the electrician will remove the old junction box and install a new one. If your home predates 2015, then it likely has, at most, a 100-amp junction box. The standard since 2015 is to have a 200-amp box. It’s a good idea to upgrade to that even if you don’t need the extra power currently, pardon the pun. After all, you might want to add an extension onto your home in the future or sell it. Having an upgraded junction box will make your home more attractive to buyers.
Final Testing and Cleanup
Once all the wires are connected throughout the house, then the electrician will connect them to the junction box. Each wire will then be tested to see if it the connections are good. Once the electrician completes the unpowered tests using special equipment, the electrician will turn the power back on and retest all of the installed wires. Often, electricians will also replace all of your outlet covers as part of the service. In some cases, too, they’ll replace the outlets themselves if they only adhere to older electrical codes or if there is some other problem with them. Once everything is tested and shown to be functioning correctly, it’s time for cleanup to the state your home was in before the beginning of the rewiring project.