For plaster holes or cracks, Beeny advises, "Instead of painting over the cracks, fill them properly and youshouldn't be troubled by them again." It may require more time and elbow grease now, but it'll save you a lot of work later. http://www.housebeautiful.com/home-remodeling/renovation/how-to/a3399/how-to-fix-scratched-and-creaky-floorboards/Click here for steps to fix plaster problems >> - HouseBeautiful.com