Painting - Massive paint chipping

I just bought a house built in 59 and the paint in the bedroom is literally flaking off everywhere in little tiny pieces. I know it needs to be sanded down before I paint again.

My question is, how much sanding do I need to do? Should I sand until the paint stops flaking and then primer or do I need to go through the color completely?

I can send a photo if that will help.

Thanks

If the paint is flaking off the wall, I would recommend using a brush to remove the loose chips. A stiff brush will remove the chips faster without all the sanding dust. Then wash the wall with TSP or spic and span. Hit it again with a stiff brush. Then prime with Zinsser 123 to seal the remaining paint to the wall and to prepare the wall for new paint. If the chips are protruding sharply from the primed coat, sanding them lightly to remove the sharp, obvious edges will help the appearance. Then another coat of Zinsser 123. Then paint.

Peeling as widespread as this sounds is likely due to inadequate bonding in the first place. The original wall was probably contaminated somehow. The Zinsser will stabilize the wall to hold the new coat of paint.

I had a similar problem, used the method of scraping, priming, sanding, priming, then painting. It looks great and the new paint has not failed. The first painting attempt had paint failing at the end of the first day.

Hope this helps.