Viance makes wood last. Viance is a joint venture of DowDupont™ and Venator Chemicals LLC and a leading innovator in developing environmentally-advanced wood preservatives for the wood protection industry. Our preservatives and protectants are used in treated lumber for residential, commercial, industrial and agricultural applications. This includes treated wood to build decks, porches, railings, posts, fencing, gazebos, playsets, and borate retreatments for residential interiors.