Epoxies and PolyUrea Vendors please make sure I'm understanding this correctly.

[haugy]

I've been searching for hours and have gone back and forth on past discussions in here, but none really called it out clearly.
I do understand that the Vendors have to do business in here and that none want to talk badly about the other, so I'm going to try to phrase this question in a manner that vendors and people can answer and not "cross the streams".

I'm looking at a 2,000sq/ft floor. I've had epoxy before which was great. But as things have become more available, options have expanded. And for what this is going to cost, I'd really like to make an informed decision with all the new items out there.

So here are some things I've observed from reading, researching, and questions. Can y'all help me in the sense of, are my statements correct or not, and please provide some detail as to why not if they aren't.

1) Epoxies vary by MIL thickness of course, but typically Epoxy can be a higher MIL thickness than a PolyUrea floor?

2) The main difference between Epoxy and PolyUrea's are the application rates and process? (Single parts vs 2-part; Longer pot life's vs shorter: Cure times)

3) Chemically they are not alike, but both have about the same resilience to chemicals, heat, and wear & tear?

I'd appreciate any other insight. Right now I've gone through most of the vendor's products in here, and my issue goes back and forth from actually choosing Epoxy, or PolyUrea. Both seem to suit my needs, so that's why I'm looking for clarity on the items above to be absolutely sure, which will help me decide.

 

[Shea]

I'll try and help you out. We are more of an information site than a vendor, so we don't have a product to sell.

1) Mil thickness is determined by solids content of the epoxy and coverage rates. As an example, a typical water-based epoxy with 50% solids may be recommended by the manufacturer to apply at a particular coverage rate that will result in a wet film thickness of 5 mils. As the epoxy cures and the water evaporates out of the coating, the dry film thickness will shrink to 2.5 mils.

A 100% solids epoxy may be applied at a coverage rate that provides 12 mils WFT. Because there is no water or solvents to evaporate out as it cures, the coating does not shrink and will achieve a DFT of 12 mils. This is why 100% epoxy works so well over an imperfect surface. It will fill all the little irregularities and not shrink to expose them. What you see wet is what you get dry.

The higher the solids content, the thicker the WFT can be. A typical commercial quality epoxy offered by the vendors here will achieve approximately 9 mils thickness and much higher depending on the product.

The user friendly DIY single-part polyurea offered by many vendors here are solvent-based and run in the area of 70% solids +/-. They cannot be applied as thick as higher solids epoxy. Most DFT's run 4-6 mils. There are higher solids polyurea that can be used, but they are 2-part and not recommended for DIY due to their extremely short pot life. Usually around 20 minutes total.

The thickness of any one coating that is not 100% solids has a limit to how thick it can be applied. If applied too thick, the carrier agents (water or solvents) will begin to get trapped and not be able to escape when the surface begins to cure. This creates all kinds of problems, bubbles being one of them.

2) That is only part of it. The majority of polyurea concrete coatings are U.V. stable and epoxy is not, regardless of what kind of additive may be mixed in with it. Direct sunlight or strong indirect sunlight over a period of time will cause epoxy to amber or get a yellow tint. The commercial quality epoxies are much better at resisting ambering, but they will still amber under the right conditions over a set amount of time.

The single-part polyurea that the vendors offer have much better abrasion ratings than even the best quality epoxy. This creates a more durable wear surface that will last longer over the years.

Epoxy tends to be more susceptible to tire marks than polyurea is.

3) Polyurea tends to have better resistance to more chemicals than epoxy, but there are exceptions. Acid is one that comes to mind. The increased resistance is relative though and does not mean that epoxy will not do well.

As explained above, polyurea is a better wear surface.

In general, high solids epoxy makes for a great build coat. It can hide imperfections and thickness to your floor. It also costs less than polyurea. A hybrid coating system of high solids epoxy and a polyurea clear coat are one of the best values. However, if not going with a full flake coverage (flakes are U.V. stable), you may have to deal with ambering later if the floor sees a lot of sun.

The single-part polyurea kits tend to be more expensive. However, they are more user friendly because you don't have to mix two parts together and you have more time to get it down. If your floor is in fairly good shape, then mil thickness is not as much of a concern. Plus, it's U.V. stable if you don't go with a full flake coverage. It's the coating system that is the least likely for people to make mistakes.

I'm sure I've missed a few points and others will add to this, but I think this may help you get a better idea of the differences between the two.

 

[Andy Smith Jr.]

I did my floor with Armorpoxy last fall and it turned out great. The system i used an epoxy primer, 100% solids epoxy base coat with flake, and 2 part urethane as top coat. The urethane has done really well on my garage floor which sees a lot of abuse.

-Andy

 

[BillK]

I think it would help people answer if you mentioned the intended use of the area.

 

[haugy]

I'll try and help you out. We are more of an information site than a vendor, so we don't have a product to sell.

1) Mil thickness is determined by solids content of the epoxy and coverage rates. As an example, a typical water-based epoxy with 50% solids may be recommended by the manufacturer to apply at a particular coverage rate that will result in a wet film thickness of 5 mils. As the epoxy cures and the water evaporates out of the coating, the dry film thickness will shrink to 2.5 mils.

A 100% solids epoxy may be applied at a coverage rate that provides 12 mils WFT. Because there is no water or solvents to evaporate out as it cures, the coating does not shrink and will achieve a DFT of 12 mils. This is why 100% epoxy works so well over an imperfect surface. It will fill all the little irregularities and not shrink to expose them. What you see wet is what you get dry.

The higher the solids content, the thicker the WFT can be. A typical commercial quality epoxy offered by the vendors here will achieve approximately 9 mils thickness and much higher depending on the product.

The user friendly DIY single-part polyurea offered by many vendors here are solvent-based and run in the area of 70% solids +/-. They cannot be applied as thick as higher solids epoxy. Most DFT's run 4-6 mils. There are higher solids polyurea that can be used, but they are 2-part and not recommended for DIY due to their extremely short pot life. Usually around 20 minutes total.

The thickness of any one coating that is not 100% solids has a limit to how thick it can be applied. If applied too thick, the carrier agents (water or solvents) will begin to get trapped and not be able to escape when the surface begins to cure. This creates all kinds of problems, bubbles being one of them.

2) That is only part of it. The majority of polyurea concrete coatings are U.V. stable and epoxy is not, regardless of what kind of additive may be mixed in with it. Direct sunlight or strong indirect sunlight over a period of time will cause epoxy to amber or get a yellow tint. The commercial quality epoxies are much better at resisting ambering, but they will still amber under the right conditions over a set amount of time.

The single-part polyurea that the vendors offer have much better abrasion ratings than even the best quality epoxy. This creates a more durable wear surface that will last longer over the years.

Epoxy tends to be more susceptible to tire marks than polyurea is.

3) Polyurea tends to have better resistance to more chemicals than epoxy, but there are exceptions. Acid is one that comes to mind. The increased resistance is relative though and does not mean that epoxy will not do well.

As explained above, polyurea is a better wear surface.

In general, high solids epoxy makes for a great build coat. It can hide imperfections and thickness to your floor. It also costs less than polyurea. A hybrid coating system of high solids epoxy and a polyurea clear coat are one of the best values. However, if not going with a full flake coverage (flakes are U.V. stable), you may have to deal with ambering later if the floor sees a lot of sun.

The single-part polyurea kits tend to be more expensive. However, they are more user friendly because you don't have to mix two parts together and you have more time to get it down. If your floor is in fairly good shape, then mil thickness is not as much of a concern. Plus, it's U.V. stable if you don't go with a full flake coverage. It's the coating system that is the least likely for people to make mistakes.

I'm sure I've missed a few points and others will add to this, but I think this may help you get a better idea of the differences between the two.

Great info Shea! Thanks for helping me with that. I've read through your site, but couldn't find a comparison as clear as this. I'm sure I missed it.

Based on your feedback it would seem that Single-Part Polyurea's might be better for my application. Due to the size, and limited crew (me and wife) I think not having to worry about mixing fast and accurate, and short pot lives would make the job more obtainable for a party of two. I will have a brand new floor with a fresh ground profile after 30 days, so I shouldn't have to hide much (crossing fingers).

It seems that based on your notes that Polyurea's seem to have better endurance, chemical resistance, and UV stability. Are they the essential future of floor coatings vs epoxies?

I did my floor with Armorpoxy last fall and it turned out great. The system i used an epoxy primer, 100% solids epoxy base coat with flake, and 2 part urethane as top coat. The urethane has done really well on my garage floor which sees a lot of abuse.

-Andy

Thanks for the feedback. I've seen many of the Armorpoxy posts, and it does look like a great product.

I think it would help people answer if you mentioned the intended use of the area.

Sure. It's a full blown everything shop. From wood working to metal working, to building cars and boats, to dragging things across the floor. When not working I need the shop clean, and I mean CLEAN. I'm a neat freak, big time, and some of my items are very old so I want to keep the area clean for storage as well. So I normally run a low flake profile so it's easy to sweep and clean.

 

[Shea]

It seems that based on your notes that Polyurea's seem to have better endurance, chemical resistance, and UV stability. Are they the essential future of floor coatings vs epoxies?

While there are some definite advantages of polyurea, particularly in a garage environment, epoxy will always have a place in the floor coating industry. There are many reasons for this that I did not cover here.

Sure. It's a full blown everything shop. From wood working to metal working, to building cars and boats, to dragging things across the floor.

Keep in mind that dragging some things across the floor is going to cause damage with any coating.

 

[haugy]

While there are some definite advantages of polyurea, particularly in a garage environment, epoxy will always have a place in the floor coating industry. There are many reasons for this that I did not cover here.

Keep in mind that dragging some things across the floor is going to cause damage with any coating.

Yep, wasn't knocking Epoxy. My last shop had it, and it was great. And I only made minor damage to it, but I was careful when dragging. Thanks again for the insight.

 

[Garage Flooring]

I've been searching for hours and have gone back and forth on past discussions in here, but none really called it out clearly.
I do understand that the Vendors have to do business in here and that none want to talk badly about the other, so I'm going to try to phrase this question in a manner that vendors and people can answer and not "cross the streams".

I'm looking at a 2,000sq/ft floor. I've had epoxy before which was great. But as things have become more available, options have expanded. And for what this is going to cost, I'd really like to make an informed decision with all the new items out there.

So here are some things I've observed from reading, researching, and questions. Can y'all help me in the sense of, are my statements correct or not, and please provide some detail as to why not if they aren't.

1) Epoxies vary by MIL thickness of course, but typically Epoxy can be a higher MIL thickness than a PolyUrea floor? Yes, typically your total system thickness with epoxy will be 12 Mils - 20 Mils and up. Polyurea can apprach that with multiple coats.

2) The main difference between Epoxy and PolyUrea's are the application rates and process? (Single parts vs 2-part; Longer pot life's vs shorter: Cure times) That is a difference. Polyurea is more UV stable and chemical resistant and while technically softer than epoxy it tends to be more durable. Epoxy is definitely preferred when a lot of repairs need done

3) Chemically they are not alike, but both have about the same resilience to chemicals, heat, and wear & tear? No. Most of your chemical and wear resistance with epoxy coatings comes from a urethane top coat. Polyurea is the same all the way through. That said evey product has its own testing

I'd appreciate any other insight. Right now I've gone through most of the vendor's products in here, and my issue goes back and forth from actually choosing Epoxy, or PolyUrea. Both seem to suit my needs, so that's why I'm looking for clarity on the items above to be absolutely sure, which will help me decide.

Please see above

 

[FJ4FUN]

Return to service time is considerably quicker with polyureas as well. It will take 2-3 days to apply a typical 3 coat epoxy system and then add more time for the final urethane clear coat to fully cure.

A "high" build epoxy floor will offer superior impact resistance to polyurea and advanced urethane clear coats provide excellent abrasion resistance. We recommend a minimum of 21mils DFT for our 3 component epoxy system.

If U.V. exposure is a concern go with a full broadcast of flakes.

 

[Armorpoxy]

Shea, perfectly said! For these reasons we offer both epoxy systems, one and 2 part polyurea and polyaspartic systems. Often back in service time or temperartures can dictate the choices. In our experience though all of these high performance coatings seem to have the same lifespan.