I have moisture damage on a couple joists and a bit of the sill (band?) in a part of my crawl space. With frenchdrains, gutter drain changes, and a vapor barrier I seem to have stopped the damage and dried out the wood, but I would like to "clean" it, some of it is very dark in color. Also, I may decide to put pieces of 2x6 between the sill (?) and the subflooring at the end of the joists where some of the wood is damaged. And possibly sister in a new piece of joist. But th epoint being I want to make sure any mildew etc is dead before I sandwich a piece of wood against the old stuff. ANybody have suggestions for chemical products? Deck cleaner? Bleech and water?? Any suggestions will be greatly appreciated.