Protect exposed outdoor woodwork, such as unpainted fencing and decks - unless they're made of a tropical hardwood like teak, or the manufacturer recommends against treating - by painting on a coat of a highquality wood preservative, such as Sikkens Cetol ($30 a gallon, at paint stores).
Frequency: Every three to five years.
Last updated December 20 2007: 9:44 AM ET