Most timber floors can be sanded. We obviously need some timber to sand, but 1-2mm is enough. Cracks along the edges are a sign that your boards are getting too thin and you may be on your last sand.

Timber Floor Sanding and Polishing
Most timber floors can be sanded. We obviously need some timber to sand, but 1-2mm is enough. Cracks along the edges are a sign that your boards are getting too thin and you may be on your last sand.