Repairing plaster walls after electrical work?

jerseyguy1996

I am in the middle of a project to replace all of the electrical in my 100 or so year old house. Many of the old outlet and switch boxes were offset from the stud with a steel bracket. Because of this I had to tear out some fairly large holes around the boxes to get to the stud so that I could pry out the steel bracket where it was anchored to the stud. Now I need to repair it. My thought was to repair the hole completely and then cut new openings in the repaired wall for the new outlet boxes and switch boxes. I was wondering if anyone has any insight into how to repair these holes. Pictures are below:

This is an example of the amount of wall I had to chisel out to get the switch box out.




This shows the different layers that make up the wall. It appears to be a gypsum board base with a layer of plaster (actually looks like cement) and a finish layer of plaster at the surface.







These are some other holes I had to make in the wall to pull out the old cable. It was stapled to the stud up in the wall so that was my only way to access the staple.

jerseyguy1996

Okay not sure what is going on with the pictures. Flickr has changed the way that they do the links to pictures.

Okay.....I got the images to work through photobucket. Not sure why flickr changed the way they do it.

forresth

I'd try the stickon patches that are used for doorknob holes.

Scuba_Dave

The old cable could have been cut off & left abandoned in the wall
No need to cut the wall open to remove
So long as both ends are cut short & out of the box

jerseyguy1996

That was the plan originally but as it turned out there was a weird random 2X4 running horizontally through the wall about half way up the wall. I didn't have a drill bit long enough to get all the way through the top plate of the wall and through that 2X4 to run my wires so I really needed the hole that the old cable was occupying to run my new wires. I also needed the old cable to pull my "wire pull" string up through the wall. It was either take out a big section of the wall in order to get my drill bit up through that weird horizontal 2X4 or just make a small hole, get the staple loose, tie a string to the end of the cable, pull the cable up and out of the attic with the string tied to the end of it and then use that string to pull my new cable back down into the wall. I still don't know what that horizontal 2X4 is for.

jerseyguy1996

I will check those out. Do you think those will be "meaty" enough to support an outlet box or switch box?

Mirz2000

Wow, it's kind of cool to see that old plaster... There are not many old houses in my area. I'm not an expert, but aren't those holes kind of big for a wall patch? You can buy small squares of sheet rock at Home Depot (I think they sell 2'x2' squares) and just cut/patch/mud. It's only a few little holes, I wouldn't imagine it would take too long. That's probably what I would do.

forresth

no. but it would be good for the other holes.

I have done what you want in the past, in a wall of very nearly identical construction. I cant remember why I had a hole there, but it was pretty sizable gap even after adding in the double box. I put some short stick in an ancored them on another part of the were there wasn't a hole with screws through the plaster mess, then covered the screw heads up when I was fixing the rest of the area.

If I were to do it again, I'd probably tape the box were I want it, with the wire already running in. Then use a can of that expanding foam to hold it all securely. cut back the foam if need be then putty over to finish it out.

That crap ranks right up there with duct tape as far as I'm concerned. too bad it takes a week to get it off your hands.

jerseyguy1996

This is actually what I was thinking of doing after I cover the hole and cut my new opening. I just need to fix the hole first. I think I may just cut the opening all the way to the next stud so that I can screw in a new gypsum board base. Then I will go ahead and either plaster over the gypsum board so that it matches the existing wall, or just fill the whole area in with joint compound which will be easy to sand smooth.