The physicochemical properties of two newly developed dirt-resistant cool white coatings were systematically measured in light of the relevant standard testing methods, and the influences of dirt accumulation and washing on the long-term cooling performance of cool coatings were investigated and discussed. Both cool white coatings owe their outstanding physicochemical properties to the optimized formulations, high glass transition temperature and minimum film formation temperature of selected aqueous self-curing acrylic emulsions. The high solid content was also influential. Dirt accumulation leads to a decline in the cooling performance of coatings, which may be almost fully restored by simply washing the coatings with a mild soap solution. (C) 2012 Elsevier B.V. All rights reserved.