Is your wood deck stained or discolored? Several products are available for dealing with these stains and related problems. Commercially-available powder or liquid-concentrates have a base of non-chlorine bleach or oxalic acid; a detergent may be part of the formula. Bleach-based products eliminate mildew, acid-based materials handle graying and stains. Some products may darken woods such as redwood and cedar, so be sure to test any material in an inconspicuous place.
Always wear rubber gloves, goggles, and old clothes when working with these chemicals and follow the directions explicitly. Caution: Never mix detergent containing ammonia with household bleach; the resulting fumes can be highly toxic.
