I was responding to Monwheels who has only a few cracks +skimcoat - indeed very do-able by anyone with some arts& crafts ability. The roughcoat + finish plaster can be bought at a specialised bldg supply store (not HD or Menards.) Ive just used Gardz on repairs + any raw plaster Ive found but OP might want to research which primer if its very old type of plaster Yes a bit of a learning curve - but generally worth it for old house owner if there are more rooms with issues than just the one. The skill set needed for crack repair is nowhere near what is necessary for a big job re-doing a whole wall of traditional 3 coat old style lime plaster over lath or board. Thats assuming one is using a bonding agent in place of mesh tape that sits on the surface - I would agree that amateurs do NOT do well with mesh tape. I had to undo all the crack repairs my PO had blobbed on -they looked like giant scabs all over the walls! My plaster guru taught me that mesh tape or any of the fabric bridges should NOT be used - reason being it shouldnt be recracking again in any major way -but if it does you want to be able to get at it to fix it again and/or address the problem thats causing it (may have been a poor quality application to begin with). FWIW, repairs I did 10-20 yrs ago are still holding with no sign of recracking. But as the saying goes, your mileage may vary. Theres a lot of different approaches to how to repair old plaster, and all old houses are different.

Cheap fabric softener mixed with hot water OR vinegar and hot water both work well to remove paste. The trick is to get it on the wall and let it sit about ten minutes, long enough for the chemicals to do their job. A extra wide putty knife has been my favorite tool for this chore however it can ding the wall if you get too carried away. I usually do both a roll of towels at he baseboard to catch drips and a plastic tarp over the rest to catch flying debris. I like to wipe the putty knife after I use it into a pail so it is clean for the next swipe on the wall. Sometimes my aim into the bucket isn't what it should be and it's a nice help to have that plastic there on the floor to catch mistakes. Paper that has been removed and dried is just as nasty to remove as paper from a wall.

It probably doesn't matter what you use really. I would use a green scrubbie pad and whatever tool you choose that gets the wall wet. I would just use a squirt bottle with hot water. This is a fairly normal experience when someone has used sizing on drywall actually. My theory is that the sizing combines with the residual paste that is left on the wall and creates this rubberized goo. This is why we don't use sizing on drywall, but I know for years it's what everyone working in the paint stores was telling us this is the proper thing to use. From now on, prime!

If I don’t wish to remove the current multiple layers of wallpaper on my plaster walls would using paintable wallpaper over them make it any easier to remove later than simply painting over them? There are parts of the old paper that would need repaired before we could do either. If you want to know the why to this question read on, its long, but I have very strong feelings about why I don’t wish to try to remove this paper. The full situation: We’ve been slowly remodeling our early 20th century house. Most of the walls are plaster except for the back half of our upstairs which was added later and is wood paneling. Every inch of the house is covered in wallpaper. The original plan was to eventually drywall the paneled rooms upstairs and to remove the wallpaper to the original plaster downstairs. Re-doing walls however is much further down our current to-do list so in the interim I’ve painted over the wallpapered-paneled bedroom walls. I’ve learned from this that if the wall and paper is in good shape you can barely tell there is even wallpaper under it, but if they are not every imperfection will show. Here is the before and after of my daughter’s room. Even knowing it’s painted wallpapered I always have to look very hard to find the seams. In our bedroom however I see the creases in the paper the minute I walk in (it’s still a 1000x better than the old wallpaper was!) I have also now experienced removing wallpaper from old plaster walls and I don’t wish to go through it again. We removed the wallpaper from my son’s bedroom in the old part of the house. The paper removal was itself was fine, but the walls were in terrible condition and covered in lead paint. Dealing with these issues took about 10 weeks. Those walls are beautiful now, but I am in no hurry to repeat the disruption and stress this caused. I am now considering what I want to do with the walls in our main living space downstairs. These have many, many layers of wallpaper on them. We saw evidence of this when taking down some crown trim and from some “helpful” wallpaper removal by our 6 month old pup. We’ve been dealing with the wallpaper, most of which, while dated is at least somewhat neutral in tone. However, we are talking about removing a fake beam in order to be able to place our TV on that wall and the current wallpaper only goes up to it. My husband has talked of putting drywall over the plaster. This not only seems weird to me but problematic in that much of our original trim would likely be damaged in the effort and we would never be able to match it exactly. At this point I feel like our best option would be either to paint the current wallpaper, or to put paintable wallpaper over it and paint that. Would it likely be easier to remove paintable wallpaper in order to restore the walls at some point if that is what is wanted or would it equally hard? I’m almost considering this more for someone who comes after us because frankly the only way I foresee us re-doing these walls the “correct” way would be if we had enough money after my children grow up and leave home to have a professional come in and do them all at once. Honestly, that seems unlikely to me, we’re older, with young kids trying to save for retirement, and college and remodel this house. We’ll be lucky to have enough for retirement and I don’t know that I’d want to stay in such a large house when the children are gone anyway. I know nothing about hanging wallpaper, but I do know how to paint it, so I think that would “easier” for me, and I also can’t imagine texture on every wall, I’d really have to find something super subtle. Anyway, I’m simply not up for removing the paper and dealing with what’s underneath, so what’s the next best thing?