A few years ago, I restored a home in Kansas City, Kansas. It was built in 1920 and was lost by its previous owners to a HUD foreclosure. One of the problems we faced with the old house was the wiring. It had the classic knob and tube wiring to go with it’s classic architecture. We didn’t have a giant budget for the home, so we had to leave some of the knob and tube in place. With plaster over lathe walls, if you’re going to rewire, you have to contend with how to handle the wiring without making a royal mess of the walls. If the walls are shot, that’s great, you’re going down to the studs anyway. But, if you’re going to save your walls then you need to find another way to rewire, unless you don’t mind a lot of patching of your plasterwork. I don’t know about most people, but when I fix a plastered wall, you know it’s not original equipment.
While we were remodeling the KC house, we considered using chains to drop wiring through the attic into the stud bays on the second floor. We could have also fished wiring up from the basement into the lower level walls. But with limited time and limited budget, we decided to leave the old wiring that was working fine intact and only address the wiring in the newer portions of the house that we were drastically remodeled. I must say the building codes KCK at the time seemed to be a rather “liberal” and the inspectors never brought up. While we did the remodeling several years ago, I must admit that leaving the knob and tube wiring in place has often crossed my mind. I find myself asking was a good decision?
At the time were remodeling the house, I often consulted books on old houses including, George Nash’s Renovating Old Houses (a great book, by the way). There are a variety of different opinions on knob and tube wiring, however several people said if it works, it works. Of course, the problem is it’s virtually impossible to track down a short in knob and tube wiring since the hot and common leads don’t run together. But in our old house, the old wiring was fine and functional, and the new wiring that was handling the greater loads was all up to modern standards. Hopefully the house hasn’t burned down in the meantime.
As an old house enthusiast and a dedicated do it yourselfer, I still rely on books and websites to help me improve my skills. One of the websites I follow is Fine Homebuilding. And, I subscribed to their daily e-mail tips. Recently I received a tip that addresses the problems of rewiring an old house without disturbing the plasterwork. It’s actually a simple concept that is similar to Cove Mould wiring, although it’s not visible outside the walls.
It’s actually a clever idea that hides the wiring behind the baseboard and protects it underneath a metal covering so can’t be accidentally penetrated by a finishing nail (or the cable Guy). With this tip, he simply runs the wiring below the finish plaster in a gap that sits behind the baseboard and in the corners he puts a fairly severe bend in the wire to accommodate the change of direction. It seems like a good idea to me. While, I’m no expert I can recognize a good idea when I see one. Here’s the link to the tip from Fine Homebuilding. Good luck with your old house.
http://www.finehomebuilding.com/how-to/tips/rewiring-vintage-house.aspx
Denver Home Tips 
This looks potentially really helpful. Thank you! You would still run the wires to your receptacles within the walls, I’m imagining, right?
Hi Marta- sorry to be so slow to respond. Works been a little crazy as we wrap up summer business. You’re right about getting the wiring up to the receptacles in their standard locations. Once you can get the wire into the empty stud cavity, it’s business as usual. Hopefully, you don’t have to tangle with lots of old insulation. Fortunately (sorta), most old houses don’t seem to have any insulation. Old work receptacle boxes work great on even most plaster walls.