Choosing the right type of finish can dramatically slow the weathering of wood, protecting it from long-term exposure to the elements. Appearance, durability, cost, surface type, ease of application, and maintenance should all be considered when selecting an exterior finish.

Two basic types of wood preservatives are used to protect wood surfaces from weathering: those that form a film on the wood and those that penetrate the wood surface.

Film-forming materials include paints, solid-color stains, and varnishes. Penetrating finishes include preservatives, water repellents, and pigmented semitransparent stains.

A newly updated FinishLine fact sheet from FPL offers a wealth of information to help you choose the right finish for your outdoor wood.  For more detailed information, see Chapter 16 of the Wood Handbook, Finishing of Wood.