And for that reason, spar varnish is used when it comes to varnishing wood that is to be used outside. Spar varnish is purposed to project long-lasting protection to your piece of wood. It is designed to withstand harsh elements and save your wood from them.

What is spar varnish used for?

Spar varnish is perfect for outdoor projects and for raw wood used for exterior doors and trim on rustic homes. In addition to protecting the wood, it also provides natural ultraviolet light protection. Spar varnish is often used on items that will be near or on the water, like a wood boat, decks, beach chairs, etc.

What is the difference between spar varnish and regular varnish?

Last but not least, every spar varnish needs to protect itself and the underlying wood from the sun. Regular polyurethane and varnish contain little, if any, UV blocking additives, and that alone makes them a poor choice for exterior application. Without UV protection, varnishes and wood quickly break down and fail.