Varnish VS. Polyurethane: What's the Difference?

ECOS 07/30/2018
do i need varnish

"Do I need varnish or polyurethane?" If you've ever gotten stuck asking yourself that question, you're not alone. Plenty of people wonder whether their home needs varnish or polyurethane, and while many think they're interchangeable, they actually have two separate and distinct different uses. Here's a quick guide to help you understand the basic differences between varnish and polyurethane.

What is varnish for? Varnish is often used as a general term for any wood finish, but its traditional definition explicitly includes alkyd resin, oil, and other solvents. It typically cures and creates a thin and glossy covering over the wood. Varnish is ideal for water-exposed outdoor decks and deck chairs because it has a high solid content and water resistance.

Polyurethane comes in two main varieties: water-based and oil-based. Similarly, it can either be purely synthetic, or blended with a resin to create a liquid-plastic like application. Water-based polyurethane is generally better for indoor pieces like desks, nightstands, and picture frames, according to Bob Vila.

"Often used to finish hardwood floors, the newer water-based oil-modified polyurethane lends a more robust level of protection than traditional water-based poly. However, any water-based polyurethane is more susceptible to cracking from heat and UV damage, so intricate wood carvings or surfaces that will be exposed to the outdoors may be better protected by an oil-based product," writes Manasa Reddigari.

Health Concerns
As we've discussed in the past, many traditional flooring and painting materials are created with harsh toxins and VOCs that can affect your health. In fact, in a recent study, participants spent six full work days in an environmentally-controlled office space at the TIEQ lab at the Syracuse Center of Excellence. In this space, VOC levels were reduced to approximately 50 micrograms per cubic meter and 40 cubic feet per minute of outdoor air per person. They found that, on average, cognitive scores were 101% higher than in conventional workspaces. With these results in mind, if your flooring is more than one year old, many of the VOCs will have dissipated already. Otherwise, go for organic finishing options VOC-free materials.

So there you have it -- the next time you ask yourself, "do I need varnish or polyurethane?" you'll be able to know for sure! For more information about painting floors, contact Ecos Paints.