I’m currently trying to decide between a 100% solids epoxy or two coats of Polyurea for my new garage floor. The garage faces south and I expect it to be open around 150 days per year. How long can I expect before the floor starts to yellow if I go with epoxy? Any comments from those who have had their epoxy floors for awhile? If the floor starts to yellow can you just scuff up and reapply top clear coat? Any insight would be greatly appreciated. Thanks! - Jeff
Epoxy UV resistance?
- Thread starter 20cent
- Start date
theoldwizard1
Well-known member
In general, epoxy does not hold up well to UV. Some are better than others.
Shea
Well-known member
An epoxy coating will begin to amber within the year if you have a south facing garage that will be open that many days of the year. Polyurea would be the obvious choice.
If you want the high build that 100% solids epoxy can provide, you can always add a matching colored top coat of polyurethane. Like most polyurea, polyurethane will not amber either.
If you want the high build that 100% solids epoxy can provide, you can always add a matching colored top coat of polyurethane. Like most polyurea, polyurethane will not amber either.
majerus
Well-known member
How noticeable is the amber on say a full flaked grey floor?
Shea
Well-known member
If you are going with a full flake floor you can just top coat with a couple coats of clear polyurea instead of epoxy. The color flakes are U.V. resistant and completely cover (for the most part) the epoxy underneath. And of course the polyurea is U.V. resistant as well. Plus, you will get better wear, scratch resistance, and chemical resistance with polyurea. Problem solved 
With low to medium broadcast flake over a grey epoxy base could I get away with one topcoat of clear polyurea? Would the grey base still yellow over time from UV? Also, would there be any adhesion issues with polyurea over epoxy base? Thanks for all the ideas, it has been very helpful.
mrobins297aaa
Well-known member
I have 100% solids epoxy coated floor, no top coat.
It has yellowed around the door openings on the south side, you can see just how far the sun reaches in the building. It didn't take long maybe year or two.
It's been down 7 years come June, it it has held up extreme well, it has not lifted anywhere. I went with a light flake, just my preference.
The floor is beige even though it looks grey in the pic.
It has yellowed around the door openings on the south side, you can see just how far the sun reaches in the building. It didn't take long maybe year or two.
It's been down 7 years come June, it it has held up extreme well, it has not lifted anywhere. I went with a light flake, just my preference.
The floor is beige even though it looks grey in the pic.
Attachments
LegacyIndustrial
ALLIANCE MEMBER
Clear coats(any type) will not protect epoxy from ambering.
You can topcoat with pigmented urethane or go with a product like our Nohr-S Polyurea.
Sent from my iPhone using Tapatalk
You can topcoat with pigmented urethane or go with a product like our Nohr-S Polyurea.
Sent from my iPhone using Tapatalk
Jaguar Fan
Well-known member
For a clear coat on top of my epoxy, I used Devoe Devthane 379UVA Aliphatic Urethane Gloss. The underlying epoxy is Devoe Devthane 224HS.
There is no yellowing at all.
See the "UVA" in the 379UVA product number? It has some form of UltraViolet light Absorbing/blocking technology that prevents the UV light from getting through to the underlying epoxy.
I have a garage floor I epoxied and clear coated back in 2008. The garage door faces west, and this is in a suburb of Las Vegas so we get a ton of sunlight. About 4 to 5 inches of the epoxied garage floor extend out beyond the roll-up garage door, so that section is constantly exposed to daytime sunlight & UV light.
There has been zero yellowing or chalking. The section outside the garage door is identical in color to the portion inside the garage door, and they look the same way they did 10 years ago.
Devoe Devthane 379UVA Aliphatic Urethane Gloss Enamel is a high performance, two-component chemically-cured aliphatic urethane gloss finish.
There is no yellowing at all.
See the "UVA" in the 379UVA product number? It has some form of UltraViolet light Absorbing/blocking technology that prevents the UV light from getting through to the underlying epoxy.
I have a garage floor I epoxied and clear coated back in 2008. The garage door faces west, and this is in a suburb of Las Vegas so we get a ton of sunlight. About 4 to 5 inches of the epoxied garage floor extend out beyond the roll-up garage door, so that section is constantly exposed to daytime sunlight & UV light.
There has been zero yellowing or chalking. The section outside the garage door is identical in color to the portion inside the garage door, and they look the same way they did 10 years ago.
Devoe Devthane 379UVA Aliphatic Urethane Gloss Enamel is a high performance, two-component chemically-cured aliphatic urethane gloss finish.
Our comments on the above agree, all epoxies can possibly yellow over time, even if protected with a UV protective topcoat. If this is a concern, then do a full broadcast with UV protecting topcoat,or use polyaspartic or polyurea as the base coat since these won't yellow.
We do though get very, very few reports of our epoxy yellowing when protected with the topcoat, but we always disclose that this is a potential issue with epoxy. For this reason is why epoxies are not used outdoors on sidewalks, driveways, etc.
We do though get very, very few reports of our epoxy yellowing when protected with the topcoat, but we always disclose that this is a potential issue with epoxy. For this reason is why epoxies are not used outdoors on sidewalks, driveways, etc.