Wallpaper and Wallcoverings - removing painted over wallpaper

Can anyone provide any suggestions for removing wallpaper which has been previously painted over (and indicate the difficulty of such a project)? I don't want to repaint over it, as the previous homeowner did, for fear that the finished product will bubble and/or continue to show seams. In case it matters, the walls are old plaster walls. Thank you in advance!

As you probably already know stripping painted wallpaper is often harder to do than unpainted. I would take a knife and score the paper well so that the water you use to help loosen the glue will be able to penatrate the paper. You can also buy a 'wheel' [sold anywhere wallpaper supplies are sold] that has multiple cutting edges that makes the job easier - it also eliminates cutting too deep and scoring the plaster. If the plaster is in good shape I don't think wallpaper removal will adversely affect but I rarely work on plaster walls.

Another option is to use a power sander with 40 or 60 grit sand paper,then apply the wallpaper remover.

If it is not bubbling now it probably won't after you are done if you don't strip it.

Sounds like a real pain to joneq. I might opt for cutting out any bad seams or bubbles then priming just those spots with BIN by Zinsser before filling with joint compound then priming everything with Zinsser cover stain and painting.

You can substitute the cover stain for the Bin when sealing any cut out seams. When filling any cut out places just fill the places you removed and not much more. You can leave it a little proud of the remaing painted wallpaper, but not too much you will just need to sand it off. You do need to hide the edges though.

Try wallwik. Its a fairly new product, but removed 3 layers of paper in my house-two of which had been painted over. I wasn't working with plaster, but unfinished drywall--no damage. I'm assuming any plaster wall was finished/painted at some point--normally with multiple layers of paint, so you probably won't harm the plaster.

We removed 4 layers of wallpaper with paint on the top layer by using a scoring wheel (paper tiger by Zinsser) and then spraying Zinsser DIF wallpaper stripper on it. I then scraped the paper off with a tool that looked like a small window squeege but had a long blade on the end. We have plaster walls and this method worked really well for us.

How long did it take to remove your wallpaper? I am looking at this problem as well but it is in a big room and is really getting me down.

We had this same issue too. We used fabric softener and hot water half and half. Put it into a spray bottle and it worked so well! Our first room was only 10x8 and it took half a day. But we had the advantage of it starting to peel on its own so it was easier.
When we got down to the brown stuff adhesive maybe? It was justa matter of washing it off with a old rag.
It was a much cheaper alternative to the chemicals you buy in the store.

FredandRetasMom, It took us about 5-6 hours to do the whole 12' x 15' room with a 10' ceiling. My wife ran the paper tiger, I sprayed the solution on with a garden pressure sprayer, waited about 15 minutes and then I scraped the paper off. We did 4-5' wide sections at one time. It seemed to take 2 rounds of this cycle to get it all off.