Dear Glenn: We painted the color lock siding on our house six years ago with a primer and Weatherbeater Ultra (polyurethane added), 25-year-guaranteed paint. The integrity of the siding is still good, but we have accumulated mold on the south and west sides of the house. We would like to repaint with your recommendation on how to deal with our mold problem.

Susan, Altoona, Pa.

Dear Susan: There is no bleach in Eco-Wash by ConcrobiumXT, (866) 811-4148, www.concrobium.com. So it will not harm the paint. If the surface is in good condition then no painting is needed.