greetings fellow plasterers!

i am readying to do some stucco valentino. the surface has wallpaper on it, which my clients applied primer on top of because they were told you could just prime and finish overtop of it! this seems funny for painting or a thin finish of course, but since i am doing the thick valentino, must i remove the paper? no doubt the prontomuro will hide any seems, it's just a question of adherence. it looks like the paper is adhering to the wall pretty well, no pealing or anything. what do you think?

and if i am to remove it, what's your favored method?

I wouldn't do it, I'd remove the paper first but of course I haven't been doing this as long as some, just my gut feeling. At some point that paper will loosen then your in trouble.

In the past I have had some clients insist on leaving the paper up, so I had them sign a disclaimer. I explained that the finish was only as good as the paper it was on... I have gone back over the years to do other rooms for them and it still looks good. It is a judgement call, but you should always take it down when you can. If you seal it, make sure the primer is oil base. The water base primers will just soften the paper and cause it to start to release, so will any plasters you apply if not sealed first with oil base. You can test this by applying a test area of Joint Compound across a seam, see if the paper starts to bubble up while it dries. JC will stay wet about as long as the prontomuro if put on the same thickness. If you are going to remove it, there are products on the market you can get, or just use warm water with dishsoap, roll on a few times & it will loosen up. Peel the first layer off and re-wet the paper backing in the same manner. Others have suggested putting up a thin sheet of plastic to keep it wet longer. I intend to try that the next paper removal I get. Never bid doing this, tell them you need to charge by the hour, because you never know how it is going to come off. It could be large strips and take thirty minutes or can be like small gum wrapper pieces and take days. Plus it may take the top layer of the sheetrock off in areas and that will have to be patched. Good luck!

Prontomuro is put on a little heavy. So all that moisture will come out thru the top and bottom if possible. My vote is to remove.

I would remove it. I would try dif and the gel together. Someone on here also suggested to lay some plastic over it and let it soak. May take awhile for the moisture to penetrate. If it still wont come off after all that,..leave it.

Ya'll forgot to note that the client has all ready applied a coat of primer.... my call would be to check the wallpaper closely, any loose corners? any loose seams..? Any air bubbles, run your hand on surface you can hear a hollow sound if any air bubbles.? If everything is tight I would reprime with oil primer just to be sure it is sealed really good. If there are any loose seams etc..RUN!. The only way you will get it off after being primed is to steam it off...the electric steam rental machines take hours to produce a tiny amount of steam. If one can be found you can steam with a propane heated steamer it will give you enough steam to remove anything, but they are nearly impossible to find...So your next chance would be to remove the losse corners..looose seams and then prime. Again I would put a big disclaimer on any finish you put over wallpaper.

I have removed wallpaper that has been primed, and painted. Sometimes it comes off, sometimes it doesnt