# epoxy; solvent or waterborn?



## petethepainter (Jan 24, 2011)

hey guys, i'm installing a 1500 sq. ft. floor over old concrete and i'm shotblasting all of it and grinding where needed. this will be a classroom to train paramedics in a building used for parking and stocking ambulances. my question is what product should i use? i've used sherwin williams waterborn epoxy for vertical surfaces, but never on floors. i've only used solvent based epoxy's on floors over new concrete or old nasty floors after a ton of prep. fumes are not a problem because people are in and out all day and the area im doing is in a seperate part of the building. the floor doesnt need to be nuke proof, but it has to hold up to medium foot traffic, nothing fancy, just a solid white or lt. grey gloss. any help is appreciated, thanks!..........pete


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## ReNt A PaInTeR (Dec 28, 2008)

Lol, you are doing the job already too late to be asking advice on materials to be use don't you think. How do you get your price without knowing what materials to use ?


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## Workaholic (Apr 17, 2007)

Solvent epoxy. 

Are you a professional Pete?


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## petethepainter (Jan 24, 2011)

yes, i am. its been a few years since i've done any epoxy and there are so many new products out there. i bid the job for sw armorseal 1000hs. this is the type of product i've always used in the past and i'm comfortable using it. i was wondering if anyone had had good results with the low or no voc stuff. i got #s on several different systems but bid the job @ $100. a gallon. i start prep on monday and was only looking for advice. i'm by no means an epoxy expert obviously, but it's work.


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## Workaholic (Apr 17, 2007)

I would go with what you speced it for.

Welcome to the forum Pete.


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## petethepainter (Jan 24, 2011)

i know what i'm using, just looking at other options or recomendations from likeminded pro's, not sarcastic out of work jerk-offs like yourself! thanks for your help


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## petethepainter (Jan 24, 2011)

Workaholic said:


> I would go with what you speced it for.
> 
> Welcome to the forum Pete.


 thanks!


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## NACE (May 16, 2008)

What profile will be left after shot blasting? This will determine the coating system. If you blast to a profile of ICRI 3 or about 50 grit sandpaper, you will need at least 12-15 mils DFT in that environment. Solvent based polyamide epoxy is work horse but has slow return to service times. However a good durable system. Thin first coat 50% as a primer then two coats high build polyamide over it. Water based epoxy is ok for foot traffic too. 100 solids will be overkill for foot traffic IMO. Polyeurea or polyasprtic have very quick return to service and are incredibly durable but require more then brush and roll.


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## NACE (May 16, 2008)

What profile will be left after shot blasting? This will determine the coating system. If you blast to a profile of ICRI 3 or about 50 grit sandpaper, you will need at least 12-15 mils DFT in that environment. Solvent based polyamide epoxy is work horse but has slow return to service times. However a good durable system. Thin first coat 50% as a primer then two coats high build polyamide over it. Water based epoxy is ok for foot traffic too. 100 solids will be overkill for foot traffic IMO. Polyeurea or polyasprtic have very quick return to service and are incredibly durable but require more then brush and roll.


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## captainblando (Aug 8, 2010)

lots of epoxy doesnt have solvent in it, its a thermosetting polymer it doesnt need solvent. but yes traditional epoxy is better .


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## captainblando (Aug 8, 2010)

pro's doesnt have an apostrophe in this instance btw


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## Metro M & L (Jul 21, 2009)

NACE said:


> What profile will be left after shot blasting? This will determine the coating system. If you blast to a profile of ICRI 3 or about 50 grit sandpaper, you will need at least 12-15 mils DFT in that environment. Solvent based polyamide epoxy is work horse but has slow return to service times. However a good durable system. Thin first coat 50% as a primer then two coats high build polyamide over it. Water based epoxy is ok for foot traffic too. 100 solids will be overkill for foot traffic IMO. Polyeurea or polyasprtic have very quick return to service and are incredibly durable but require more then brush and roll.


What does DFT stand for? Dry film thickness?


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## NACE (May 16, 2008)

Yes. Dry film thickness. A floor like that should have at least 12 mils DFT.


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## c65jones (Mar 27, 2011)

To your original question, I would stick with the solvent epoxy finishes. Latex paints have come a long way, but floors are one area that solvents still are the way to go. Surface tolerant epoxy (Devoe Coatings Bar-Rust 235) topcoated with a clear urethane (Devoe Coatings Devthane 379) will make most any job turn out great. Latex epoxy finishes just don't bond, wear, or hold up to solvent spills like one would hope.


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## drybrush (Sep 1, 2011)

*variation on original question*

If anyone's still watching this thread - looking for a means of clear-coating (low sheen preferred) over bar-rust 235, but unlike the OP's situation, in my case it's gonna be in full sun exposure. ICI tech rep tells me that chalking of 235/delaminating of urethane will occur quickly if I go with any clear urethane _he _knows of to cover the 235. 

Anyone have good luck with something along these lines?


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## NACE (May 16, 2008)

Devthane 379 Clear or 378. Should not delaminate if the 235 is not too old. If its been exposed it will chalk and the urethane will delaminate because of chalk or to hard and glossy.


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## drybrush (Sep 1, 2011)

thanks NACE - 'I want to believe'...have you actually done this & seen lasting results? maybe I will just have to try it. ICI tech rep was saying that chalking will _accelerate _under the clearcoat due to UV transmission - counterintuitive to me - and spawn the feared delamination. But then the 379UVA data sheet supports him somewhat, too ("...Not recommended for exterior use over epoxies, alkyds or oil-base paints..."). Concerns me especially since they're both DeVoe products.

In my situation, I'd planned on color-sanding the final multicolored 235 surface (maybe 600-grit) before clearcoat, so it would be clean. Still think it's a good system?

--Dave


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## NACE (May 16, 2008)

I think it is a good system still. I have done over 150 epoxy floors myself. I do like clear coats on interior floors but I think you have a good point about clear exterior in that the epoxy will eventually chalk and cause the clear to delaminate. However, I usually use a urethane, 379 or 378 in the same color as the floor for exterior exposures. Most of the Aliphatic Clears have very good UV resistance. I did some brass ship props over seven years ago with Aliphatic Urethane Clear that were polished to a mirror finish, and they wanted it to stay that way. These props are part of the marina's signage and are exposed to an exterior marine environment all day. They said they would tarnish in a month. Those props still look like the day they were polished seven years later. I used three coats of Aliphatic Urethane Clear.


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## LINE-X (Aug 17, 2011)

Skip the epoxy with urethane topcoat and just go with a polyaspartic (aliphatic polyurea).


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