I would never paint of wallpaper at a clients house since we cannot provide a finish that we could warranty. However, at my house I ended up painting over the wallpaper since they did not prep the walls properly when they originally installed it. Uses an oil based primer because the water based will activate the adhesive on the edges of the wallpaper. If you can, get wallpaper stripper and try to take it off before painting over it since will will look better properly prepped. They have all of the tools that you need at Home Depot.

Your success with that will be a roll of the dice. It depends upon many variables (type of prep that was done initially, type of wallpaper, type of glue that was used and the list goes on). SawHorse has the right idea but you will still be able to see the seams. The risk is that when you put any kind of liquid on wallpaper there is the possibility that the glue will come loose and begin to peel. It may take a week, a month of even a year. Then, you have a bigger mess than when you ...»

I typically end up with a textured finish or faux finish in the end because if I put that much work into prepping the walls might as well make it extra special. Wallstreat does this professionally every day so I would listen to what she has to offer when it comes to finishes.

I agree with the others above here. Although I have done this a few times by specific request of homeowners, I would never choose myself to paint wallpaper. It will forever look like painted wallpaper and not a painted wall.

As said already, if it is tightly glued to the wall, it is possible. To hide the seams, prime the seams (oil) then spackle and sand each seam smooth. Oil prime the entire room and proceed as usual with paint. I've done it a few times with no problems. Hope this helps.