Designed to clean the dirtiest pine, cedar, redwood, cypress and birch decks and siding asphalt shingle and cedar shake roofs and badly stained and oil spotted concrete in the fastest and easiest way possible. 1 Quart makes 2-1/2 Gallons and 1 Gallon makes 10 Gallons. Gallon diluted 9:1 with water covers about 2000 square feet. Water-base. Being free of bleach, it will not harm shingles or bleach wood. No scrubbing needed.