[oscarMadison]

I have what I think is plaster walls. Where the trim is removed it looks like concrete. In one spot where I can see the back of the wall I don't see slats, but what looks like some kind of drywall.

Is this plaster on drywall? If so how hard is it to cut a square hole in it? I figure drywall would okay, but not sure on the plaster. I'd like to extend a single receptacle box to a double so I can fit in a phone jack/cable plug. Currently, the cables come up through the floor. I'd like to do the same thing in the other bedroom, it's got an old style four prong jack.

 

[timthetoolman]

Yes plaster with a drywall backing is quite common. Usually 2 ft by 8 foot pieces of drywall were used for this installation method. It is fairy easy to cut through with a sawsall and although some slight chipping of plaster may occur, it will be minimal as opposed to cutting other installation methods of plaster such as steel mesh-AHHH Terrible to cut and wood lath.

 

[fireguy]

Yes plaster with a drywall backing is quite common. Usually 2 ft by 8 foot pieces of drywall were used for this installation method. It is fairy easy to cut through with a sawsall and although some slight chipping of plaster may occur, it will be minimal as opposed to cutting other installation methods of plaster such as steel mesh-AHHH Terrible to cut and wood lath.

To expand on timthetoolman's response. Use either Lennox or Milwaukie blades, 18 tooth bi-metallic. Wood blades will tear the plaster out.

 

[Thurman]

I actually have a hand saw, much like a drywall saw, for doing just this, enlarging electrical boxes. It has a "grit" type blade instead of teeth, made for cutting plaster with metal mesh backing actually, should work on your plaster/drywall combo. I got mine at Lowe's, I think it is their Kobalt brand, it has a blue handle anyway. I'm sure others have these also. Thanks, David

 

[oscarMadison]

Thanks guys. Now to figure out which receptacle. As far as phones, the hallway has a little built in section for a phone. May have see if I can pickup an old style phone to put in there.