Exterior varnish, stain, penetrating-oil finish, polyurethane or paint – what’s the right option for exterior wood finishing?
Polyurethane with a correct ratio of resin and oil is a smart finish for exterior use with expected longevity. It’s readily available at a minimum cost. Moreover, it keeps the natural wood grain visible, which is another point of their popularity. But still, it’s not the best exterior wood finish, as you have to put more layers and recoat once or twice in a year!
The “spar” or “marine” varnishes are similar to exterior polyurethane. They require many coats to ensure perfect UV-blocking while recoating each year. Experts call them short-lived beauty, as they give robust protection for a relatively short period.
But an epoxy sealer with an exterior varnish topcoat can genuinely offer a durable finish for outdoor woods. Despite their higher expenses, they might be your best bet as an overall perfect finish for exterior wooden surfaces. Next to it, a penetrating oil finish with a high-quality formulation is an excellent finish if you want the grain visibility with durable performance.
But, paint (added with primer) is doubtlessly the best solution for protecting outdoor wooden surfaces in terms of longevity. On vertical surfaces, a paint coat can last 10 years or more, while on horizontal surfaces, it may not cross 5 years. No alternative has yet been able to outperform the protection timespan of a quality paint. Unfortunately, you can no way see the wood color or grain if you apply paint. Outdoor stain, a form of thinned paint, can be a great alternative with almost the same durability, but it will cost more than the heavy-bodied paint.
So, overall, among the contenders, paint wins.
For your convenience, you may check the following professional-grade best exterior wood finish.
Outdoor Paint – Prestige Exterior Paint and Primer
Outdoor Stain – DEFY Extreme Exterior Wood Stain
Exterior Epoxy Sealer – TotalBoat Penetrating Epoxy Wood Sealer
Exterior Varnish – TotalBoat Spar Varnish
Outdoor Polyurethane – ZAR Ultra Fast Dry Poly
Penetrating Oil – Cabot Australian Timber Oil