Should We Use Polyurethane?

I’ve asked myself this question with each and every project that involves wood. I’ve painted cabinets, stained cabinets and I’ve even painted cabinets with stain. For all of these projects; I start with a solid plan that may take a few turns; such as changes in design or material used. Sometimes I plan to use a polyurethane finish coat and in the end I don’t and vise-versa. A recent post, “How to paint cabinets / wood to get Pro Results”, and accompanying video, has lit a fire that needs to be put out…

Do I like using a polyurethane finish?

The answer is Yes! But, the next question – Should you always use a polyurethane “finish coat” after painting cabinets? – Well is a little more complicated. As I’ve mentioned in all my posts that involve painting cabinets; poly is always optional, so the long answer is subjective. – BUT as a DIY’er and person who has experienced painting cabinets at this level (I’m no expert); the short answer is No.

Why not always use a polyurethane finish coat?

Keep in mind this is entirely my opinion. You can read about my experience and take it with a grain of salt, or you can experiment yourself and decide what the answer is for you. I think for many, they will agree with my experience and others maybe not. There’s really no wrong answer here.

Polyurethane – what is poly even used for?

The hardware store is cluttered with a variety of finishes. From water based, oil based and in between. To top that off, you have a variety of sheens, liquid vs gel, brands and formulas that make deciding and choosing a finish coat a hard decision. Poly is a “finish coat”, used as the last application, to “seal” your topcoat. So poly seals your painted wood, or stained wood for example. It acts as an extra layer of protection. Poly is easy to clean and can give your projects a high shine if you so choose. Don’t like shine? You can still protect your project with a “matte” finish. My ultimate favorite sheen is Satin for painted cabinets and most stained wood. A matte finish is especially good when trying to keep that “rustic” feel.

I won’t go into all the specifics, so let’s just break it down between the two most common; water-based or oil-based. Just like with paint, water-base cleans up with soap and water (before it dries) and oil-base uses some other solvent, such as mineral spirits. Rumor has it; oil-based can yellow over time and water-based does not. Both water-based and oil-based come in a liquid application, while oil also comes in a gel. Most polyurethane finishes can be wiped on with a sponge brush, lint-free t-shirts or a sprayer. Some people recommend a quality, synthetic nylon brush; but, I prefer sponge brushes over bristle. Of course, you need to read the label to determine the application options. Not all brands and types are the same. For example, you wouldn’t spray a gel polyurethane. You can read more about “what is polyurethane, and the differences between finishes” from this great post I came across.

So when would I choose to use a poly finish coat?

As I have mentioned, I really like poly, I just don’t use it for everything. I do however use it sometimes in small areas of my project, such as the drawer and door faces of cabinets, which get a lot of traction. I have painted projects where I used no poly and more than a year later, they look as good as the day I painted them. (Using Benjamin Moore Advance). Here’s a list of when I would or would not use poly.

Do use poly when:

You’re applying a water-based paint to wood. Although I always recommend Benjamin Moore Advance (an alkyd paint) for painting wood, some may have their reasons for using a water based. I can’t see why, but if you do, I’d recommend a poly finish coat.

You’re staining wood.

You’re painting wood with a gel stain.

You want to ensure extra protection for an alkyd or oil-based paint, such as high traction areas.

You want extra shine or a smoother feeling.

When you may consider not using poly:

You’re using an Alkyd (waterborne) based paint.

You’re using an oil based paint.

You want the convenience of easy touch-ups and refinishing.

There you have it. My opinion on using poly. To use or not to use.. poly, is simply a choice. Whether you use it or not, will be entirely up to you. For the above mentioned applications, I can’t see how it can hurt to provide extra protection. The only drawback is when it comes to refinishing “painted cabinets” – If you need to refinish a door face, for example, you need to remove all the polyurethane finish coat before you can refinish with paint. If you have no finish coat (no poly), on your door face, you can either lightly sand the area and touch-up; or lightly sand the entire door face and refinish (respray). Lightly sanding being the key, vs heavily sanding to remove all the polyurethane.

So what poly finishes do I like best?

Whether water-based or oil-based, that really is up to you. I tend to stick with water-based. It works great and creates a hard, durable finish. I’ve used oil based before, particularly when painting my cabinets with a “dark” gel stain. General Finishes makes a great oil-based, gel poly finish. I like it a lot. Very easy to apply with a thick sock. I would however only use this on dark finishes, as I would be afraid of it yellowing over time when used over light colors.

All-in-all, I tend to stick with water-based applications. I really didn’t see much of a difference using water vs oil polyurethanes, except for how easy it is to apply an oil-based gel. But, you should not have yellowing issues with a water-based, so I say stick with water. I’ve used Varathan, Rustoleum, General Finishes, Minwax and other brands and all seemed to work equally as well. G.F. is supposed to be a higher quality product and I would agree with that. As always, read the label of your chosen polyurethane for information on yellowing, application, safety etc.