Originally posted by midget:
Well, I was working on troubleshooting some issue this lady was having the other day, and I was just not getting anywhere...there was power to everything else on the circuit...just not the receptacle and switch in the 2-gang box, which I believed to be the end of the circuit...how long do you guys troubleshoot somethign before you cut the wall open to see what's going on? The guy was syaing there might have been a wire that got cut from when all this new stuff was put in. Then, when you decide to cut open a wall, or an opening for a box, etc...how do you go about it? How do you make sure you're not hitting wires, pipes, etc? Sawzall, utility knife, what your choice of weapon to make your cuts? This is sheetrock we're talking about...but woudl it be different, if the wall surface was different? Do you repair the wall yourself when you're done, or call a sheetrock/texture guy?
In my experience, people are
very reluctant to have their walls cut open. Most of my clients live in houses built in the 1920s and 1930s, and in those days the walls were finished with plaster on wood lath. Often there are plaster archways or textured surfaces, too. Patching such surfaces to the satisfaction of the client is not easy, which is why I avoid it as much as possible.
Sometimes you don't have much choice, though. In these cases, it's often more trouble than it's worth to try to trace a bad connection that's buried in the walls somewhere, so I just cut the connection at the nearest convenient existing opening and run new wires.
You'll still have to do some wall opening, though. Sawzalls are nice for demolition work, but they are a bit crude for something like this. Drywall is easy to open up cleanly just using a jigsaw, but plaster on lath is much more problematic. Plaster is brittle (cracks easily), and lath will rattle back and forth (breaking up the plaster) once one of the support ends of the lath gets cut. A rotary tool (like RotoZip) solves the rattling lath problem, but they rotate at a minimum of 15,000 RPM and take a while to learn how to control precisely without using a guide.
In situations like you describe (on a plaster/lath wall), I like to score the outline of the new opening with a utility knife and use a cold chisel to remove the plaster, leaving the lath exposed. Then I carefully use a jigsaw (very slow speed) to finish cutting the lath to make the opening. It's more time-consuming this way, but it results in a good, clean opening that is much easier to patch. I like to leave as much of the lath in as possible, as it can serve as a good support for a drywall patch. I've found that 3/8" drywall on top of lath often lines up well with the existing plaster surface of the wall. Then there's the taping and mudding process. I think the drywall and tape & mud guys work for a lot less than licensed electricians, though, so it's probably better to let the homeowner hire that out after the electrical work is done.
Plus there was about 3 j-boxes just in the basement...in the cieling...who puts them in the cieline? LOL they are really noticeable up there. 
I didn't charge them for the troubleshooting, though, since I didn't get anywhere. People shouldn't charge someoen if they didn't accomplish anything, right?
