Wood gutters are a rarity these days, but if your home does have them, they require a little extra attention. Wood gutters need to be resealed every two years. Wood gutters need to be resealed during the dry season. The first step in caring for wood gutters is a good sanding, followed by an application of wood preservative. Finish caring for your wood gutters with two coats of asphalt-aluminum roof paint, and your wood gutters will look like new.