Updated: April 2024
Before you can decide whether water based polyurethane or oil based polyurethane is best for your project, you need to define what you want the end result to look like and how you want it to perform.
Let’s start with why you would use polyurethane in the first place vs. other types of wood finishes such as shellac, lacquer, varnish, etc.
Based on my 30+ years using and formulating wood finishes, it is best to use a urethane when your primary objective is maximum chemical resistance and film hardness, i.e., durability. It’s no accident wood floors, for example, are usually finished with urethanes.
With that in mind, here is a head-to-head comparison of how water based polyurethane and oil-based polyurethane stack up.
There can certainly be exceptions (some of which are noted below) but the below overview should make your decision easy 90% of the time…
Final Finish Look and Feel
A well-engineered, water based polyurethane will be equal in clarity to oil-based polyurethane. The main difference is usually color: water based polyurethanes are completely clear and (again, if well engineered) will not yellow over time.
This is ideal if you want the natural color of your wood to remain constant. Some people prefer the warm, “amber” hue that oil-modified polyurethane imparts to wood, but keep in mind, this “yellowing” will continue and intensify over time.
In terms of “feel,” it is true that oil based products interact with the grain less and require fewer coats to get a final finish. However, when the necessary number of coats of both products are applied they will typically have a smooth but hard feel to the finish. Some will find the “feel” of oil based poly to be softer, but in truth oil based poly tends to continue to harden and get brittle over time leading to cracking in the finish on projects subject to variations in movement, while water based poly typically maintains its flexibility and will not crack with age.
Winner: Tie (+1 to each)
Durability
Oil based polyurethane had the edge here for a while, but water based polyurethane (especially the self-crosslinking variety like Emtech® EM9300) has caught up – it’s now equal to solvent based products regarding scuff, mar, UV, water, and corrosion resistance. Some people find oil based poly dents and peels easier, whereas water based poly might scratch easier. Keep in mind that there are variations to each urethane type, so read the product spec sheet from the manufacturer carefully.
For instance, we use a polycarbonate resin in our coating as opposed to a polyester resin found in most polyurethanes on the market. Polycarbonate resin is more resistant to ultraviolet light and the cured film remains neutral in its color effect on many wood species for a longer period of time.
If you’re trying to make something virtually bombproof, oil based may be the way to go, but the hazardous additives and flammable solvents you’d need means you would almost be making a bomb.
Winner: Tie (+1 to each)
Health & Safety
Oil based poly is made with highly flammable and toxic solvents to allow the urethane resin to level and form into a cured film. Not only is the coating hazardous to your health, but the clean up process requires exposure to high odor hydrocarbon solvents now well documented to cause short- and long-term health problems.
A well-engineered water based poly usually contains little or no ingredients considered “hazardous chemicals” as defined by OSHA. It is not flammable, making your insurance company and local fire department happier.
Likewise, a good water based poly will have significantly lower (up to 50% lower) volatile organic compounds or VOCs. Couple this with the ability to clean up with soap and water and the benefits in health and safety stack up quickly in favor of a water based formula. This is so important, I’m awarding a bonus point here.
Winner: Water Based Polyurethane (+2)
Achieve this Look & More with EM9300
Emtech® EM9300 is an interior/exterior-grade waterborne polycarbonate urethane that resists marring and scratching, repels water and chemicals, and blocks UV light for an ultra-clear, non-yellowing finish that lasts.
Drying and Re-Coat Time
All things being equal (temperature, humidity, etc.) oil based polyurethane will take about two to three times longer to dry between coats compared to the faster drying water based polyurethane. This usually means you can finish a project in one day with a water based formula while it can take 2 or 3 days to finish a project with an oil based formula.
Winner: Water Based Polyurethane (+1)
Number of Coats Needed
The water in water based polyurethane tends to “react with the grain” more, so you often need to apply more coats to achieve a smooth, finish. A good rule of thumb: for every coat of oil based polyurethane, you may need to apply at least two coats of water based polyurethane.
Winner: Oil Based Polyurethane (+1)
Number of Coats Available
With a water based poly, you have unlimited coats available. Want to put on six layers? Go for it. Don’t want to sand between coats? Provided your recoat time is within 16-18 hours there’s no need to sand for adhesion when using Emtech® EM9300 Polycarbonate Urethane. Outside of 24 hours dry time? A cleaned substrate and light scuff sanding is all that’s necessary for EM9300 to form a strong chemical bond with a previous coat.
Oil based polyurethane, on the other hand, is prone to “sheeting,” scratching or chipping after the first couple layers. Its hardness in the drying film requires thorough sanding between coats to help form a mechanical bond.
Winner: Water Based Polyurethane (+1)
Compatible Substrates and Adhesion
Both water based and oil based polyurethanes are extremely versatile; they will bond to nearly anything including wood, (non-ferrous) metal, fiberglass, stone, cement and carbon fiber.
Remember, though, water based formulas tend to be non-yellowing as they age and oil based formulas tend to amber. With wood substrates that is sometimes desirable, but with many other substrates a yellowing finish is usually something you want to avoid.
Winner: Water Based Polyurethane (+1)
Cost
The raw materials used to make water based polyurethane tend to cost more than that of oil based polyurethane. However, the prices for crude alkyd resin used in the manufacturing of oil-modified polyurethanes continue to creep upwards. Still the final price you pay for a high quality water based formula is typically higher.
You could argue that there are very real but hidden costs to your health and the environment over the long term when using oil solvents, but let’s give one point on short-term costs to the oil based formula.
Winner: Oil Based Polyurethane (+1)
Application & Equipment
You can find both types of polyurethane in brush- and spray-friendly versions, so “ease of application” is a tie. Our Emtech® EM9300 is spray, brush, and roller friendly making it a great choice for any type of application method.
However, due to its slower dry time, spraying oil based poly will make everything in the area a sticky and dangerous mess to touch. This overspray can get on everything inside and outside creating a hazardous work and play environment.
Your equipment, whether using spray, brush, or roller, tends to last longer and need less maintenance because soap and water is all that’s required to clean up.
Also, you should take into account that the low solvents in water based polyurethane tends to give it a longer “pot life” (the amount of time you can work with it before it becomes unusable).
Winner: Water Based Polyurethane (+1)
If we add everything up, here’s the scoreboard:
Water Based Polyurethane (+8)
Oil Based Polyurethane (+5)
Depending on the importance or “weight” you place on the categories above, your scoreboard might come out looking differently.
For example, for me, safety to the wood finisher and the environment could easily be worth +5 points, in which case water based polyurethane wins by an even larger margin.
What do you think? Do you have experience using (or questions about) water based poly vs. oil based poly?
Please share your thoughts or read what others are saying in the comments section below.
As always, stay safe and stay creative!
I have some old 1999-2000 Michael’s (later Restoration Hardware) stained oak bedroom furniture. It’s a very warm, almost rosewood or dark cherry color, matte vs. glossy. Do you know what kind of finish was used on that line of products? I’ve searched all over for this info, as I need to refinish the top of the bedside table. I’m no expert, can’t tell if urethane or not.
Janet – Thank you for sharing your inquiry with us. No, I do not know the exact type of finish that was used on your furniture, however, considering that it was made at the turn of Y2K it is probably finished with a conversion varnish or catalyzed lacquer. A good, easy to use option for refinishing these types of finishes is to use our EM8000cv Conversion Varnish with our CL100 Crosslinker added in to it. Feel free to give our office a call to discuss this option in greater detail.
-JW-
Thanks for the article.
I am looking into options for wood floor coating for a hair salon. I am looking into the Oil-based urethane option.
WOuld that be a good fit? Thanks
Mark – We do not recommend any of our top coats for use on flooring applications. Emtech top coats are too slippery/fast, and do not meet the anti-slip properties required.
-JW-
I am burning a plywood subfloor and coating with polyurethane. Which would be preferable for this application in a high traffic area with lots of natural light?
Jackie – Thank you for our inquiry. We do not recommend using any of the Emtech topcoats on flooring applications unless an anti-slip coating is applied over it. This is due to the high slip factor of our finishes, they are very “fast/slippery”.
-JW-
We are installing pine shiplap boards on our walls. We are not sure if we should use the oil-based or water-based poly. Would you share your opinion on what we should do?
Susan – Water based finishes are much lower in odor, dry faster and depending on the type of poly you choose will not yellow.
-JW-
Excellent review, just what I needed. Thank You!
Hello, I am refinishing a kitchen table and have stained the top with an oil based minwax stain. I bought an acrylic polyurethane but don’t want it to turn yellow which I was told this could happen. What is best to use?
Gayle,
Most water based polyurethane finishes are rated as “non-yellowing”.
For the best performance I recommend our EMTECH EM9300 Polycarbonate Urethane for this specific applications.
You can find the EM9300 at http://www.targetcoatings.com/shop
Please feel free to contact us directly if you have any specific questions.
-JeffW-
What would you recommend for finishing a oak hand hewn barn beam sanded and prepped for a bench? Water or oil based polyurethane?
Teresa,
Thank you for your inquiry. I suggest that you look at our EM2000wvx Waterborne Alkyd Varnish or our EM9300 Polycarbonate Urethane.
Both can be brush-applied. The EM2000 will color-shift to a warm amber color tone as it ages, which will look really nice on the vintage oak.
The EM9300 will remain clear/non-yellowing and will magnify the existing wood grain and color.
-JW-
My wife has a porch swing that belonged to her great grandmother. It has several decades worth of layered paints in various colors that have a “chipped” almost calico finish. I’ve already sanded the swing down and removed most of the easily chipped pieces, but I want to preserve the look and finish because it reminds my wife of all the places the swing “lived”. Is a water based polyurethane going to be the best top coat?
Luke –
Thank you for your inquiry. Yes, using a water based polyurethane such as our Emtech EM9300 Polycarbonate Urethane is an excellent option.
Using water based polyurethanes will allow for a fast recoat time, very low odor / non-flammable environment, and our EM9300 Polycarbonate Urethane offer very good UV and water resistance.
I am confident that you will like the way it works and feels after it is fully cured.
-JeffW-
Thank you for your time. I’m finishing my basement and hanging 5 doors 2 bi fold doors and barn door. And casing and trim . Should I buy a sprayer? And should I use water or oil?
Larry – It sounds like nice, big job! Spray application is the fastest but not always the easiest way to go.
Are you going to the doors or do you plan on a stain/clear coat finish?
-JW-
Hi, I just purchased a new unfinished dresser and stained it with an oil based wood finish. Does it matter whether I use an oil based polyurethane or an oil based poly? In either case is it necessary to sand the stained surface first?
Thanks, Michael
Michael – Thank you for your inquiry.
It is OK to use an oil-based stain and then clear coat it with a water based polyurethane.
You have to ensure that you allow the oil-based stain to dry 12-18 hours, then lightly wipe the surface of the stain with a solution of water and denatured alcohol mixed 1:1, prior to applying the water bases polyurethane. This light cleaning will remove any oil or wax that my be sitting on the surface of the stain – which will cause adhesion or leveling issues with the water based polyurethane if not removed. Emtech EM9300 Waterborne Polycarbonate Urethane is an excellent choice for this type of application. It is rated as a polyurethane but is built with a polycarbonate resin backbone, which gives it very good UV resistance.
-JeffW-
I’d like a satin finish on a hardwood dining table, would a water based polyurethane be the best option?
Yes, our EM9300 Polycarbonate Polyurethane is an excellent choice for use on a dining table.
Visit the link above.
-JW-
hello, i need to put a clear topcoat that doesn’t yellow on new soft maple kitchen cabinets i’ve built. correct me if i’m wrong but it looks like em9300 would be the one to use. after going to target coatings web site i noticed a couple of different sprayers, witch would work best to use on my new cabinets a T75G turbine or Fuji LX-20. why and what would be the difference.
thanks
Darryl — Thank you for your inquiry. Yes, the EM9300 Polycarbonate Urethane is one of the two best options of a non-yellowing clear coat. The second option is the EM7000HBL Lacquer – which is a non-yellowing acrylic lacquer. If you are looking for maximum chemical resistance I recommend the 9300.
As for the two HVLP spray gun options offered on our site, the FujiSpray LX-20 is a compressed-air HVLP gun, so it needs an air compressor to work. A 20gal air tank is recommended. The FujiSpray T75G is a turbine driven HVLP gu, it works off of several FujiSpray electric turbines made by FujiSpray. We offer a turbine kit that contains the Q5 Turbine and a T75G gun, along with hosing and ancillary accessories.
Feel free to contact our office Mon-Fri 9am-5pm EST at 800-752-9922
-JW-
I am looking for the best way to protect/ covering / clear coat for new Acacia Spice stained butcher block countertops I will be installing in my kitchen
Robert — Thank you for your inquiry. While I personally lean towards penetrating oils for wood counters, you can use a film forming finish such as our Emtech EM9300 Polycarbonate Urethane for this application. Keep in mind that any film forming coating will chip, requiring regular maintenance. Penetrating oils are easier to repair for the average home owner.
-JW-
Hello! I am doing a huge project this summer. Refinishing indoor furniture and making an outdoor welcome sign. This is my first refinishing project and have been doing a great amount of research going into it. I have decided on a water based stain for the indoor furniture and an oil based stain for the outdoor sign with white chalk paint for letters. I plan on using water based polyurethane for the indoor furniture as I want to limit fumes and the water based polyurethane seems it is fast drying and better for furniture. I am wondering if this is true, if you have any tips for my first time, and if I am able to use the water based polyurethane for the oil based stain? Thanks.
Ally – Thank you for your inquiry. In regards to using a water based polyurethane over a solvent/oil based stain I strongly recommend that you allow the stain of choice to dry for a minimum of 12-18 hours. Once this time lapses you will then gently clean the surface of dried stain with a solution of water and denatured alcohol mix 1:1, this will remove any remaining oils or spirits that my reside on the surface of the dried stain. If not removed these oils can cause adhesion and film leveling problems hen a water based finish is applied onto the stain. If performed properly (and carefullY0 you will obtain a good bond between the water based and oil based products.
-JW-
I agree with everything except one. I found it necessary to scuff sand between coats with water based poly. If not, successive coats can peel. This has happened to me.
Hello. I am venturing into making outdoor barn quilts. I am using a 1/2″ birch ply base, one coat of exterior primer, and then 2-3 coats of paint on the design. The oil based spar tends to yellow and also is not holding up to the sun. I have one barn quilt in part afternoon shade (north facing) and another in full afternoon sun. The latter one in full sun is already cracking and peeling after one year. My main question is, would a water based hold up better to the sun? Note: I use a mix of quality craft paint (due to the large number of colors available) and exterior paint on the designs followed by two coats of spar. Should I just stick to exterior paint? Thank you for any advice, I appreciate it. Be well.
Kindness,
Megan Beachum
Crow Bar D’signs
Megan – Thank you for your inquiry. I recommend that you consider our Emtech EM9300 Water Based Polycarbonate Urethane as your clear coat of choice over the craft paints being used on your folk art. I do have a few questions about the paint you are suing, so please feel free to contact my office so we can review in greater detail.
-Jeff Weiss-
800-752-9922
I want to refinish my wood floors on the first level. The stairs don’t need to be refinished as they were covered previously. I do not plan to cover them. In CT, they have now (over last few years) banned oil based poly. I’m not entirely sure if oil based poly was used when the floors were first put in 10 years ago, but I am concerned with the color difference between oil and water based polys. Is there a way to color match the water based poly to match existing stairs hue. With oil based poly I have read that they Amber over time, at what point do they stop Ambering (sorry I don’t think that is even a word but I think you catch my point)
Jaclyn – Thank you for your inquiry. We do not make coatings that are specific to wood floor applications. The Emtech line of waterborne wood finishes are primarily formulated for furniture, cabinetry and architectural features that are above the floor line. I recommend that you contact Absolute Coatings or BonaKemi to obtain more product information for your flooring needs.
-JW-
I am installing cedar wood to the ceiling of my outdoor covered screened in patio. I would like to keep the natural color of the cedar in tact, no color change at all. I would like to have a satin finish ( no shine). Which product should I use and how many coats. My ceiling does not get any direct sunlight but I live in Florida.
Thank you
Michele,
Thank you for your inquiry. I recommend that you use our EM2000wvx Waterborne Varnish for your specific application. EM2000 will offer very good moisture resistance and has a pH that will not create a major color change of the cedar.
-JW-
Sealing a redwood slab for exterior use. Would like to keep the color as light as possible yet have excellent UV protection and a covering that would accommodate some wood movement, (swelling/contraction). Will the clear, non-yellowing EM9300 work? Are the terms “polycarbonate Urethane” and Polyurethane” the same>
Alan – Thanks for your inquiry. I recommend that you use our Emtech EM9300 Waterborne Polycarbonate Urethane as a self-sealing finish on the exterior slab you describe in your post. The EM9300 will allow for movement without the checking/cracking that can often be associated with solvent-based 2K urethanes. I recommend that you apply 4 coats onto the underside of the piece, and at least/minimum of 4-5 coats on the topside to obtain good UV protection over a season. Keep in mind that all coats require regular review and maintenance to ensure that the substrate is being properly protected.
Regarding your question about polycarbonate urethane and polyurethane being the same – No, the term polyurethane is a generic term that is used to describe a urethane coting that is made from either polyester diol or from a polycarbonate diol. The resins are classified as a “polyurethane” but each resin is made from a different type of diol ester.
-JW-
Hello,
My partner has just taken on a huge project of stripping whitewash from wood (A frame ceiling) because he wanted the natural wood color back. He used a nontoxic all purpose remover and sanded the wood down. We have been debating about whether to use oil or water based stain. I am pregnant 6 months, and I do have another place to stay at his moms for as long as I need. What would you recommend? I think he likes the look of the oil stain…
Michelle, waterbased finishes have long been considered an excellent choice from an environmental and health perspective. And today’s new waterbased finishes are becoming widely accepted for their exceptional performance, too. I’ve had great results with Target Coatings NR4000 waterbased stain, which is available in a wide variety of colors. But because the wood framed ceiling had been previously finished and was recently stripped and sanded, I’d recommend you perform a test to ensure there’s nothing left behind to cause bonding issues. Pick the least noticeable area and see how things go. Once you’ve confirmed there are no bonding problems and successfully stained the beams, should you wish, you can go ahead and apply the protective topcoat of your choice. NR4000 is compatible with all of Target Coatings topcoats, but if you’re looking for a recommendation, I’d go with EM6000 production lacquer; not only is it a top-notch performer, but it’s very easy to apply by hand or with spray finishing equipment.
Good luck with both this project and your soon-to-arrive bundle of joy!
I painted my kitchen table with dark brown chalk paint. Then I used a water based polyacrylic from Annie Sloan. I got bluish milky streaks throughout. It looked terrible. I lost the dark rich brown color. So I had to sand, prim (5 coats) then paint 5 coats of the chalk paint again. Now I need to put on the topcoats. Almost everyone says to use a polyacrylic because the oil base will yellow. But no one mentions that the water based can look terrible on dark paint.
I’m still confused.
The oil base lovers are stain table artisans.
They say cut it with paint thinner so you get thin layers.
What’s your take? I don’t want to redo this table top.
Thank you.
CP♥️
Hello, CP. It appears you’ve got a compatibility problem between the chalk paint and the topcoat. Not being familiar with that particular chalk paint, I went to Annie Sloan’s website to see if they had any recommendations for topcoating, and noted they recommend “Seal it with Clear Soft Wax and age it with Dark Soft Wax”. That gives me the impression that they aren’t endorsing topcoating with polyacrylics – waterbased or otherwise. My suggestion at this point would be for you to go back to them and ask for clarification. Incidentally, just because a company carries other manufacturer’s products (which I am assuming is the case here) should never be construed as a recommendation to use them together. The standard recommendation when trying any products you haven’t previously had good results with, is to first contact the manufacturer(s) involved, and then to conduct your own tests before committing to your project.
Good luck with this and please let us know what you came up with.
Marty
Great article, quite informative! I have to disagree on the cost evaluation however, especially now in 2022.
The cost of the product itself is NEVER the only cost of using the product. While comparing the price of a quart of oil base to a quart of water base may make it appear that oil is a lower cost, when you factor in the cost of the solvent you are using to clean up with you have to add in a quart of some type of solvent also. This always makes the cost higher unless you just have the thinner sitting around from a previous project. I also agree about the safety particularly when spraying the product, water base wins hands down.
I just installed a 380sf Southern Yellow Pine tongue & groove plank ceiling. It’s been sanded, cleaned with denature alcohol and conditioned with oil based conditioner. I’d like to stain it (I’m hoping to get it more tan and less golden) and poly it with no shine. I’m going for the rustic look. Do you recommend oil or water based for the stain and for the poly. Is there a color you can recommend? I like to see the grain show through. Thanks so much!
Thank you for your inquiry — I recommend using our EM2000wvx Waterborne Varnish over stain to create a warm color tone. Ensure that you allow the oil-stain to dry 12-18 hours, then lightly clean the surface with water and alcohol mixed 1:1 to remove any oils that may be on the surface of the stain.
-JW-
Hello, We are restoring what appears to be an empire chest of drawers…cira 1890-1900, veneered, possibly mahogany.
Naturally we would like to put the best and ‘stongest’ protection on it when sealing it. What are your recommendations? I am not familiar with EmTech products at all.
Thank you
Joy
Joy – Thank you for your inquiry. I suggest that you consider our EM6000 Production Lacquer or the EM8000cv WB Conversion Varnish.
Both will match-up with the color of aged/antique lacquer or varnish as it ages.
-JW-
Hi Jeff, great article. My wife and I are looking for a professional opinion or thoughts on which poly would work best on our live edge Maple counter top in our 1850 farmhouse. This will have a sink in one part of the counter. Because we have pets and cannot completely vacate the house, we are slightly leaning towards the water based, but like the protection that the oil would offer. Thoughts
Thanks you Sir
Hi Rick,
Thanks for your comment and question. For many of the health, safety, and easy cleanup reasons outlined in this article I am partial to EM9300 Polycarbonate Urethane with an addition of 5% by liquid volume of our CL100 Crosslinker for this project. I think the additional protection an oil might add to this project are nominal at best and the non-yellowing characteristics of a water based format will keep the light Maple wood looking great for many years. I would apply 4-5 coats for the best protection with the crosslinker added to all coats.
-Seth Kline
Have bar top made out of red fir 100 year old wood beautiful grain how best to protect & show off wood character. Thanks
Hi Tom,
Thanks for your comment. If you have access to spray equipment, I would use our EM8000 Conversion Varnish on this bar top. It’s a warm finish that will go great with this type of wood as well as very durable to protect it for years to come. If you plan to apply by hand application methods, I would use our EM9300 Polycarbonate Urethane. I would use our CL100 Crosslinker in either coating at 5% by liquid volume. This additive is a great addition for bar tops and will boost chemical resistance.
-SK