Paint Pulled off Drywall Layer

A friend of mine's roommate used oil paint to paint the entire apartment and did a terrible job of it. We have been stripping the oil paint off the walls to redo it all and in doing so, the brown layer of drywall is exposed with all the fuzzy fragments. We were told to lightly sand it and put two coats of primer on it before painting. Is there more to it than that or is that sufficient? I am attaching a picture of the walls.

You'd be better off to just paint over what the friend did with an oil based primer, and then paint over the primer with whatever paint you want. Removing the oil based paint simply isn't very feasible.

What I'd do with what you have is use a piece of sandpaper to remove the roughness on the brown paper patch, and then repair that brown patch.

The best way to repair it is to apply strips of self adhesive fiberglass mesh drywall joint tape across the patch and run it up onto the painted wall a few inches on each side. Then, paint with white wood glue diluted with enough water to make it into a paintable consistancy. As the glue dries, it'll bond the fiberglass mesh to the drywall, thereby replacing the strength of the missing paper. Apply a second layer of fiberglass mesh strips running perpendicular to the first layer, and paint over them with diluted white wood glue as well. Now, mix up a bit of all purpose drywall joint compound (you may want to thin it by mixing in some water if it seems hard to spread easily) and apply that over the fiberglass mesh. Use a bright light held close to the wall, but some distance from where you're working to cast critical lighting on your work area to make it look rougher than it really is. That will give you a better idea of where to add joint compound and where to remove it to get a smoother surface. Once it looks OK under critical lighting, it'll look great under normal lighting, and you can prime and paint.

I would wipe off the lose paper with your hand, apply 2 coats of quick dry polyurethane with a chip brush, apply 2 coats of mud. They have a product for drywall repair called Gard Z but a little pricey.
Mesh tape would raise the repair area leaving you to float out that section more than necessary. Use a hair dryer to dry the joint compound (mud) so you can get the repair done fast…

Mike
Home Repair and Improvement Houston

The product Mike is referring to is called "Gardz". It's made by Zinsser's and is sold at Home Depot.

Or, smooth out that brown paper as best you can with whatever works, apply the Gardz to seal the brown paper, and when dry, apply the two layers of fiberglass mesh over the Gardz. You probably don't really need to replace the strength of the missing paper; the wall will look find without doing that. But, if it wuz my house, I'd put some fiberglass mesh strips down to build up the strength of that area.

Skim coating a wall isn't hard. Just work with a bright light close to the wall, but far enough away so as to cast light at a sharp angle, making the wall look rougher than it really is. That will give you a good idea of where you need to add joint compound and where you need to remove it to get the area smooth. Once the area looks reasonably smooth under such critical lighting, it'll look perfect under normal lighting. Then, primer and paint.