We too had bad wallpaper covering plaster in our entire house. In one room, the wallpaper was a "pre-pasted" removable kind and came off easily. It would have been dumb to paint over this paper because it was so easy to remove. However, in all the other rooms, the wallpaper was VERY difficult to remove because it was the old variety that came off only in one inch strips. We got several quotes from professionals who refused to touch the wallpaper. At least one professional recommended that we paint the wallpaper. We then tried three different solutions. First, my husband removed the flocked wallpaper in one room. It was very difficult to remove because it was not "removeable" wallpaper but older, heavily pasted paper. He tried every tool for removal, including steaming, scoring, etc. The only tool that worked was a 4 inch razor blade scraper (not 3 in or 5 in according to him!). That was a long process and the walls were in such poor shape that we had to wallpaper over the plaster when we were done. Second Approach: In two other rooms we painted over the wallpaper. In one room, a bedroom, the paint looked great. The painted wallpaper has held up fine for 20 years. Just last year we painted it again with no problems. The second room where we painted over wallpaper was the bathroom. It bothered me to paint the wallpaper in this room because it was poorly wallpapered in the first place. There were several corners where the wallpaper was not flush with the corners, but "wrinkled", for lack of a better term. Because every inch of the room, including the ceiling, was covered with wallpaper, we just painted it. It too has lasted 20 years, but it does not look as good. The paint made the wrinkles more obvious to me. Also, we must have had a leak, because the wallpaper on the ceiling is beginning to bulge. It will have to be redone soon. I am not sure any outsider would have noticed the flaws in this room, but I did. It was a second floor bath, though, so I just lived with it. Third approach: In our dining room, I think we again stripped the wallpaper, but then my husband attempted to plaster the walls himself. BAD IDEA. Although he is very handy, this was a job that he could never get to look good, no matter how many coats he used and how many times he sanded it. (By the way, the sanding made the entire house a mess!) After weeks of trying , he finally gave up. Instead of hiring a professional plasterer, he applied a special wallpaper that was meant to be painted. This wallpaper was like canvas and smoothed out any irregularities and made the wall ready for paint. It still looks great. My advice to you would be to look into the cost of hiring a professional to either plaster or apply the coat of the substance named above and sand it. I am not sure if we ever got a quote for plastering and sanding. If it is cost prohibitive, get the wallpaper that is intended to be used on plaster walls and then paint it.

Guardz works fine - no specific need to use an oil based primer if fumes are a concern. Sanding the walls is a good idea, then guardz, then a little more sanding if necessary, skim, skim, skim again if you want it perfect, prime and finish with premium quality materials. Zinsser's Kitchen and Bath paint seems to work well in high humidy environments. Or If the walls are not painted with semi-gloss or have torn drywall paper showing, simply sand the walls and start skimming. Priming is usually not necessary over flat or low sheen paints. Do use a high quality primer over skim coated walls prior to painting with 2 top coats.

Veneer plaster is made for skim coating. Mix it with 90 minute compound mix -- 3 parts compound to 1 part plaster. Don't use plaster of paris as it will harden up so fast you'll end up throwing most of it away before you get it on the wall. You can try the above suggested mix and/or work with the veneer plaster mix alone or experiment. Use a large, wide trowel to smooth it on and make up your own "darby" with a 2 x 4 about 2' long and attempt your final smoothing with that, wait and then sand and then fill your dips again until you get a reasonably decent surface. Try to work fast, working slowly and methodically will cause more errors and you will lose sight of the "big picture" and with this kind of work you want to focus on the whole wall -- the whole job and not just a line or a lump here or there. Also, irregularities that you can't get rid of can be feathered out and a fool the eye effect can be achieved by spreading the lump or problem over a larger surface so as to remove focus on one problem area.

Ugh. I just read that both of those primers are alkyd rather than water based. Any suggestions for a water-based primer? I'm really reluctant to use an oil based paint but realize I probably need to. Christopher, is there a reason you suggest the Moorwhite over the other? I think the verticle boards on the wood siding are cedar and the 094 mentioned it was good for that. The paint that is on the house now is water-based, but as I mentioned earlier, it is completely peeling off in a lot of areas leaving bare wood exposed. Will the oil based primer stick to both of those surfaces equally well?