You want to paint your walls, but they are crumbly and you are worried this will affect the finish.
You will need
Step by step process
Ensure the walls are clean and dry and try to sand away as much loose material as possible.
If mould is present, treat with Polycell Mould Killer and allow to dry.
Apply one coat of Polycell 3 In 1 Problem Wall Primer using a roller. Once dry, the surface will be sealed, stabilised, flake-free and ready to paint in your choice of finish.