Request for advice: Can I cut a groove out of plaster wall

[Evan Dickson]

I have a room that was formerly two rooms. The house is 70-90 years old. The walls are plaster. Between the damage from knocking out the wall, and the 7 different plaster textures that exist in the now single room, I figure it would be easier to put up strapping and mount wallboard over the plaster than to repair and skim all the plaster. I've discovered stud sensors don't work through plaster and lath. My idea is to cut a groove, maybe 1" high, circling the room near the bottom of the walls and another near the tops, so I can look and know exactly where the studs are. Would this cause any structural problems to the existing plaster? I would hate to have stuff collapsing under my wallboard.

Thanks for any advice provided!

[Norminn]

If you have baseboards, you might be able to figure the stud spacing from where the baseboards are nailed to the wall. Studs aren't necessarilly regularly spaced, but could be. I would drill small holes, rather than cut a "groove" ... if the bit comes out with wood, you've hit a stud. Do that every 1/2" or so until you hit studs.

[BETA-32]

I have a similar situation (long story).

First, I agree with the suggestion to just use a drill to drill pilot holes and find the studs that way -- must less mess and easy to do.

A contractor just looked at my house and said there are basically 2 options.

The first is to rip out all of the plaster and lath down to the studs, then put up new sheetrock and trim.

The second is to apply new sheetrock right over the old plaster walls. He said sheetrock that is as thin a 1/4-inch thick is available so not much thickness will be added, so the existing trim will still look okay, etc. (I thought the thinnest sheetrock available was 3/8-inch, but he said they make

1/4-inch sheetrock.

[Evan Dickson]

Long stories are good. Which option did you go with, and were you happy with the results?

[mwlogs]

I assume you will be pulling the existing trim off and reapplying after putting up the wallboard? If so, just knock or drill a few holes around the bottom and find the studs. Using the 1/4 inch board will keep you from adding too much thickness to where you'd have to build out the door and window casings. I'd also suggest gluing the board up for the most part of the plaster is sound.

A good stud-finder will work, even with plaster and wood lath - they sense the density of the wall so it need to be able to sense a bit deeper than a cheap one might do. My walls are paster with sheetrock lath totaling about

1" thick and mine works fine at finding the studs.

[BETA-32]

I didn't decide yet. I just went through the house with the contractor last Thursday. It's a whole-house job and I am going to be doing new electric, new plumbing, new kitchen, etc. I already have a couple of ceilings out that I had taken down to the studs, and where I made two rooms into one (the LR and dining room into one big room), I have a 16-inch wide section of the ceiling out that goes across the whole room where the two rooms used to meet. All 4 exterior walls of the house are solid red clay "stone/brick" with plaster applied directly to that. So, it's just the interior walls and ceilings that are plaster over wood lath. That means I need to decide if I want to just go for the gusto now and take down most or all of the remaining plaster and lath down to the studs, or just have 1/4-inch sheetrock applied on top of what is already there.

[John Grabowski]

I don't know what your long range plans are, but I think that the best idea is to remove all of the old existing plaster and possibly the wood or wire lath under it. A house that old probably needs some electrical upgrades which could then be installed in the walls. There also may be some structural issues you were not aware of. Then you can start clean with new wallboard on the existing wood studs.

[Don Young]

This is good advice but a possible downside is that plaster studding is sometimes not as level as you would like for sheetrock since the plasterers just adjust the thickness to level the wall.

Don Young

[Norminn]

I turned my brain back on ...........if you use the drill and hit wood lath, you probably will have some wood shavings on the drill bit, but probably also find more resistance if/when you hit a stud. :o)

[Evan Dickson]

Wiring here is only 9 years old - so I'm not too fussy about removing plaster for an opportunity to invest more work into the room.

I think what I'll do in the end is leave the plaster on and use someone's previous idea to strip off the baseboards to locate the studs

- this idea seems spot on. Now that I can locate the studs, I'll mount thin boards over the plaster and thin sheetrock (1/4" thickness) over the boards.

[BETA-32]

I think you'll have a problem if you apply 1/4-inch sheetrock and it is not applied directly to the existing plaster. If you first "mount thin boards over the plaster" and then attach the new 1/4-inch sheetrock to the thin boards, the sheetrock will be too thin and will bend and flex.

[Heathcliff]

I agree -- putting "thin boards" in between seems to be inviting trouble. Gluing the drywall on directly sounds like a better idea -- would like to hear from someone who has done this successfully. What glue did you use? Previous discussions on the group have also mentioned the option of skim-coating to cover flaws, unwanted textures, etc. in old plaster. Putting up thin drywall might be easier and faster though, plus it will not telegraph cracks (current or future) in the plaster.