What is the difference between varnish and polyurethane?
Marcus Reynolds
Published May 30, 2026
While polyurethane is water- or oil-based plastic resin, varnish is older and made from resins, oils, and solvents. Because of the higher ratio of solids, varnish is less susceptible to ultraviolet light damage. This protection makes varnish an excellent choice for projects such as outside decks and exterior furniture.
What lasts longer varnish or polyurethane?
Varnish is less durable but it is more versatile and flexible. It is more durable on outdoor furniture than polyurethane because of its UV damage protection and water-resistance.How do you know when to use varnish or polyurethane?
Varnish. Polyurethane is a water- or oil-based plastic resin used for coating wood or as a wood finish. Varnish is an older type of finish made from resins, oils, and solvents, but very often, the term "varnish" is misused as a generic name for all types of wood finishing.What is the most durable clear coat for wood?
Polyurethane wood finishes are synthetic coatings that are highly durable and water resistant, making them the best clear coat for wood protection.Can you put polyurethane over old varnish?
Yes, you can polyurethane over varnish without damaging the finish. This is so because it's hard-wearing, long-lasting and durable, and with a high resin value, which allows it to resist harsh outdoor conditions.Polyurethane vs Varnish vs Lacquer
What happens if you apply polyurethane without sanding?
For some types of poly, nothing happens if you don't sand between coats of polyurethane. However, most polyurethane will not adhere properly if you skip sanding dust nibs and brush marks on the finish. The polyurethane finish will eventually peel off or become deformed.What brand of polyurethane is best?
The Best Polyurethane for Treating Artworks, Furniture, and More
- Varathane Water-Based Ultimate Polyurethane. ...
- Minwax Water Based Protective Finish. ...
- Rust-Oleum Triple Thick Polyurethane. ...
- TotalBoat Gleam Marine Spar Varnish. ...
- Deft Interior Exterior Water-Based Polyurethane.
Can you put polyurethane over bare wood?
And our method allows you to achieve the holy grail of raw wood finishing: how to finish raw wood with satin (or glossy) polyurethane without changing the wood's color or shade. Yes, it's possible.Which is better oil based polyurethane or water based polyurethane?
Oil based used to be unquestionably more durable. Today though, water based polyurethane has evolved with better formulations that are equally durable as oil based polyurethane. High quality water based polyurethanes is considered by many homeowners & flooring professionals to be equally durable.Does varnish seal wood?
METHOD 2: Use sealants for best protectionPolyurethane, varnish, and lacquer are tried-and-true sealants with excellent waterproofing properties. They're either brushed or sprayed onto clean, sanded wood and then allowed to dry completely, prior to the piece being lightly re-sanded and recoated.