Krud Kutter House & Siding Pressure Washer Conc gallon. House and Siding Pressure Washer Concentrate contains a proprietary blend of ingredients to remove tough stains from mildew, mold, algae, fungus and moss, and leaves the surface completely clean. Safely and easily dissolves stains from dirt, oil, grease, bird droppings, tree sap, and acid rain. Even removes gray weathering on wood, chalking, and oxidation. Features: Contains Sporex mold and mildew stain remover; Makes 11 gallons and cleans up to 3,200 sq ft; Water-based; biodegradable.