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How to clean painted walls
Avoid harsh chemicals on flat and eggshell finishes.
Both flat and eggshell (also called satin) latex paints look nice on interior walls because they don't bounce a lot of light. Unfortunately, these popular paint finishes can be finicky to clean.
These finishes can be damaged easily, so do not use chemicals or degreasers on this kind of paint. Mix a few drops of dish detergent in a 0.5 gallons (1 , 900 ml) of water.