[header] How to apply elastomeric paint [title] Power wash the surface for a sure clean. [step] The best way to ensure your surface is clean is to power wash it at a pressure of 2 , 000 to 2 , 500 psi. It's always a good idea to test the pressure on your surface, because it can cause damage. 
You may need to use a lower pressure or another cleaning method if washing at these pressure levels causes damage. [substeps] Don't add cleaner or bleach to the water when power washing.