Do i need any prep before painting this wall?

Question

there used to be wallpaper here. Im not sure what that grey layer on top of the wall is. When i rub my finger on the white part, this white dust comes onto my finger (dont know if this means anything) So basically what i am saying is, do i need to remove this grey coating completely off the wall, or can i just paint over it? it is a very thing layer.

heres a pic of my wall

http://i38.tinypic.com/2udysew.jpg

Answer 1

You'll need to clean off anything that is loose (including the powder) using a rag and perhaps a little bit of water (try not to use any chemicals).  Then, paint the wall with a nice thick coat of primer (something will a stain blocker in it).

The primer should seal in the gray layer and help the paint to stick.

Answer 2

I saw the picture, looks like fresh sheetrock mud and ripped paper off the sheetrock.

Put a skim coat on and sand smooth, texture to your desire, prime and paint your color choice.  You can use two coats of paint because it looks like fresh sheetrock.  Stay away for a flat wall paint, use a egg shade of satin finish.

Answer 3

It sort of looks like removing the wallpaper took off some of the paper covering the gypsum underneath. That's what wallboard is made of in case you didn't know. Have you tried looking this up on diynetwork.com? I'm not sure if regular primer would take care of that, or if you need to prep the wall in some other way first.