My daughter's attic bedroom consists of lattice walls covered in concrete, platerboard, wall paper and panel board. We are trying to repaint the room and bought the materials to strip the paper and started taking down the panel board that was on the lower half of the wall only. Turns out the previous owner used the panelboard to cover falling apart walls. I do not have the time and energy to remove all platerboard etc and start over with drywall. What is the easiest and most inexpensive way to repair sections of these types of walls. The largest problem area is about 2 by 2 feet, other areas are only inches. Any help would be greatly appreciated.

 

You can clean it off and fill and repair with joint compound.

 

If you don't have the time or energy, hire someone to do it.