This problem sometimes occurs when filled areas are not primed before painting. It is always best to prime filler and/or apply an extra patch of paint to filled areas. This is especially the case for water-based paints Tools and materials Paintbrush, primer, roller, paint

This problem can occur with some types of filler. Recoat the patch of filler with a suitable primer, or if you are painting with emulsion, prime with full-strength emulsion. Recoat the entire wall.

Extracted from DIY- Know How With Show How published by Dorling Kindersley, price £25.00. Copyright © 2006 Dorling Kindersley Ltd, Text copyright © 2006 Julian Cassell and Peter Parham