A good indication would be a spot where the wallpaper seems to be bulging out a bit--tap such areas to see if they feel hollow; you might just have failed glue, or the plaster could have lost some of its keys holding it to the lath.

I stripped multiple layers of painted paper (about 1/16" ) from my 1908 hall--and lost only a few small areas of the top coat, which I skimmed with compound. The worst area was a section on the upper stairs where there was a crack in the paper--it seems the top coat had separated leaving me about a 1' square section to recoat.

I wasn't real happy with the stripper I bought--I hear you can make your own, so I wouldn't waste money on the commercial type. Score the paper so that the warm water will penetrate, and allow it to soak a bit, then use a drywall knife or wallpaper blade to slip under an edge.
If your woodwork is original finish, mask it off first to protect it from the water.

If you do have large areas where the plaster seems loosened and can't fix it now, go ahead and put another layer of paint on--it won't hurt down the road when you do try to strip--I have several rooms with painted paper, and I just painted over it again.

The painted paper, especially on outside walls, does act as a sort of vapor barrier, so you might keep that in mind. :)

Here is a link to the hall I stripped, and other areas I haven't.

Here is a link that might be useful: House Pics At Last

One thing you really need to consider is this: Many old houses from certain eras with plaster walls never received a finish coat of plaster at all. The intention was wallpaper forever. If you remove the paper from these walls, you'll find a layer of rough, sandy plaster which is not really suitable for painting even if you could remove all the paper and its adhesive without doing any damage - an unlikely prospect in itself.

So the first thing to do is remove a little of the paper from an inconspicuous place and check the plaster surface. If it's smooth, hard and an off white color, you do have a finish coat. If it's sandy, rough to the touch and easily scraped with a finger nail, it's a rough coat with no finish coat.

As columbusguy wrote, the overall shape of the plaster is impossible to determine with the wallpaper in place. If there is a finish coat and you're determined, start with a small room and work at it over time.

If what you have is rough plaster only, there are some options. Strip the paper and coat with joint compound - a pretty major project, but possible DIY. Hire someone to put on a finish coat of actual plaster. Add another coat of paint.

Thank you both! I will strip a little in a small area and see what I have. I am thinking of doing an area around a door jamb,I have heard these are the areas that tend to crack more. Have you found this to be true? I surely don't want to get into a huge project right now but did want the walls to be somewhat smooth.
I know that I can't really sand wallpaper but would like to get rid of some of the raised areas. The previous owners installed a wallpaper border around two of the bedrooms and then painted over it. Any suggestions on smoothing these areas out? Would appreciate it!

I think I'd want to find someplace less visible than around a door frame to do the first excavation. These areas are prone to cracking because of the movement and occasional slamming of the doors, so they're not a very good indication of the overall shape of the plaster anyway.

I assume the raised areas are the vertical seams where individual sheets of wallpaper butt together and the horizontal seams where the border was placed over the paper. I really can't think of any way to eliminate them that is not a major project.

Still a major project, but one that does not involve stripping the wallpaper at all is to use wide and thin adhesive fiberglass mesh over the wallpaper. This is then be coated with joint compound. It's not a cure for plaster that's pulling away from the lathing, but if there are no bulges or places where the plaster moves when pressed or only small areas that can be stabilized with screws, it saves a huge amount of work and mess. There's a good deal of skill involved in putting on the compound smoothly, but the more you do, the better you'll get at it.

All in all, dealing with the walls may be best seen a project for the future.

You need to find out if there is a finish coat on the wall under the paper.

If the finish coat is there stripping is not hard, just dirty and slow work.

4 inch wide razor knives and a steamer and you should be all set.

The only think then is the hours of stripping.

The finish plaster should be smooth and hard enough to allow use of a razor scrapper dry for a lot of the wall.
by LOTS of extra blades.
The plaster takes the edge off the blades very quickly

I also would love to remove paper from plaster walls in several rooms - but I'm afraid to... Long-ago PO's previously paneled over 2 rooms, (suspicious, much?), the only one without that "bandaid" has very thick paper - applied with at least a 1" overlap. It'd been painted over - & sprayed with what I assume was ceiling texture gunk? I scraped/sanded the hard scratchy bumps off & repainted. Both walls & ceiling have this paper - was this something sold for this purpose - to hide/cover, (or egad, "retain"?) crumbling plaster? I know it's probably not that bad - only other projects are keeping me from it, not fear, lol.

On a side note... That's one more reason why plaster is better than drywall! I HAD to get rid of ugly wallpaper in a downstairs bath - tried an area & it pulled right off.. Good, right? Wrong. The floppers had put in drywall & papered directly to it without priming at all. Pulled a layer of "sheet" off the "rock", leaving a rough exposed-paper layer. Why go to the trouble to drywall, then apply (textured vinyl) wallpaper directly to it, so that removing the paper would literally destroy the walls? That's the difference between flippers & floppers. (Sorry for getting off topic & ranting a bit, but if it'd been plaster...).

"Both walls & ceiling have this paper - was this something sold for this purpose - to hide/cover, (or egad, "retain"?) crumbling plaster? "

Thick paper has been available for a long time for use on plaster without a finish coat, and to 'hide' cracked plaster.

Until you pull the paper off there is not any real way to tell.

Ceilings used to be papered as a matter of course.

I remember razor striping the walls of one house with oil painted paper, then going back to steam off the remainder of the paper and having the ceiling paper fall off from all the steam needed on the walls.

We are in a 1848 house and it took me 6 months to remove the wallpaper from the foyer area. It is solid brick walls covered in plaster.(all the interior walls are like this) Once I started to remove the paper with warm soapy water and a tiger stripper, I realized that the wall underneath was never even painted let alone primed. They were pretty good shape and just needed a little plaster/drywall. In another room I did the same method with warm soapy water and the tiger, but this was 3 layers of burlap was what was on the walls. This room retained a lot of moisture from the burlap and needed a little more help. Removed any lose plaster and plaster/drywall over. Been about 8 years now and no cracks showing.

it seems to be easier to remove wallpaper from plaster than from drywall -- the zinnser products on the market work nicely (paper tiger et al). as someone else said, get lots of razor blades. figure out how long you think it will take to strip the paper and triple that figure. if you have a job/life, break the task up into realistic chunks.

i have found that if i give myself plenty of time to setup the work area -- lay drop cloths, tape plastic over the molding, etc - that this time is richly rewarded at the end of the day's work and i'm not tracking old wallpaper and gunk all over the house.

I am so afraid that if I start stripping the wallpaper that the plaster will crumble and then I will be left with a very expensive fix that I can't afford to do right now because I just put all my money into purchasing the house.

Learn to patch plaster ... if you have an old house, it's an essential skill. And it is not hard. If you can spread peanut butter on a cracker, you can spread plaster on a wall.

I learned from a French baron ... genuine titled baron, who spent many weekends patching up the family chateau.

Hi guys! Okay, I couldn't decide what to do or what I would have so I just went for it. I stripped the wallpaper off the plaster. It wasn't that hard really except for the outside walls. There is some patching that has been done, I'm assuming a long time ago. The walls don't look as bad as I thought except for the outside wall. It has kind of a rough surface but I haven't wiped the walls down yet and I am hoping it is mostly wallpaper glue.
I am thinking of just doing some patching...thanks LazyGardens, I WILL learn to patch! LOL! And then just leaving it kinda like it is, paint it, glaze it, and hopefully have some kind of European looking finish when I get done.
Has anyone tried this? Do you have any paint techniques you would like to share? I would love to know as I have never tried this but I am willing.

" I am hoping it is mostly wallpaper glue. "

You had better hope and pray that it is NOT glue and is paste instead.

Skyren, thanks for the update! (It's great to read follow-ups, progress reports, etc to original posts). :-)

Regarding interesting painting techniques, Columbusguy posted pics of his - he did amazing things with paint. ("House pic's at last" is the topic line). I think he used a lot of different techniques, successfully.

Lazygardens, you've got me worried. I nearly always break the cracker! (Does that rule me out, as someone who could repair plaster? Lol..).

House pics at last