Water-based acrylic paints, such as Sherwin-Williams Duration and Behr Premium Plus Ultra, are good for most outdoor wood, states ConsumerSearch.com. Oil-based paints are best used for sappy woods, such as tannin or sap, because they have better adhesion and stain blocking qualities.
Water-based acrylic and latex exterior paints characteristically don't trap moisture beneath them, which allows wood to breath. Trapped moisture, which can be caused by applying oil-based paints, can cause the wood to rot. In general, for outdoor wood structures, such as porches and roofs, 100 percent acrylic latex water-based paints offer the best results. However, regardless of the paint used, any sort of outdoor wood must be prepped prior to painting it to achieve the best painting results. Sanding the wood with fine grit sandpaper and applying a primer before painting increases the durability and the appearance of the paint.
The Sherwin-Williams Duration line of acrylic paints is lauded as one of the easiest and most durable paints to work with by industry professionals. ConsumerSearch.com cites nine-year studies in which Duration paint was subjugated to extensive weathering elements. The paint performed admirably and needed any sort of repainting or touch up very rarely.
The Behr Premium Plus Ultra acrylic water-based paint is one of the best value based paints on the market. It is significantly cheaper than the Sherwin-Williams Duration paints but it still matches up admirably to other more expensive top of the line external wood paints.