Fixing hairline cracks before epoxy coat?

[bc_stang]

I bought rustoleum kit from HD few weeks ago for my detached garage that we built back in January. Planning to do 2 coats of epoxy. Concrete floor has not been used yet and is free of any oil spills,etc. I have washed floor 3 times already to make sure there's no dust oN the floor before I apply epoxy. Trying to make sure I prep it right as much as possible. I did noticed I have some hairline cracks in the floor. Should I worry about them and fill them with epoxy filler or epoxy coat will cover them since these are not that big? I would have to say biggest one is less then 1mm in width but runs from one side of the garage to another (24x25 garage).

Also, after the floor was done we did not make any saw cuts in the floor but it seems like some cracks are due to settling. Would it be too late now to do saw cuts in flooring?

 

[jasonvt]

I would fill the hairline cracks. Id check out Legacy's or Garage Flooring LLCs filler. I used both.

 

[LegacyIndustrial]

Unless you are using a "bridging primer", you would need to prefill them. They will telegraph through the coating.

Yes, making cuts now would be a wasted effort. Need to be done while still green.

 

[bc_stang]

Ok what do you guys recommend I should use to fill the cracks? I always thought since cracks are too thin, it will be easily covered up by the epoxy as it lays thicker then paint. Also since I am doing 2 coats, it should not be visible. Also legacy, what is bridging primer?

 

[RCStocker]

If you have hair line cracks in your floor you will only have more in the future. Just put a good sealer on the concrete and be done with it. I don't understand why people want to paint their floor. Unless you want a show room it is down right stupid in my opinion and I am a general contractor and architect. I also have a masters in art but I am an old farm boy and served a tool and die apprentice ship with GM and have worked for Boeing aircraft and the US Navy as an inspector.

Just because they make a product does not mean everything in the world should get painted with it. most of those floor paint were developed to paint basement floors.

While it looks nice it does not save the floor and only looks like hell when you start to work on it. The first time you pull your floor jack across it the nice finish is gone.

The problem is the cracking. You had a bad poor. If it has small cracks it is one of 3 things. The ground under the floor was not compressed properly. The concrete is to thin or it was a bad poor and was to wet when poured. You want to pour concrete as dry as you can and keep it wet after the poor for as long as you can. The longer it takes to dry the harder it gets. You can make concrete so hard you can not bust it up by hand. I have seen steps that I could not break and I am 6-1 and 270 pounds.

Just get a cement sealer and go to work and set up the garage. If I painted one of my shop floors people would think I had gone mad. I have 4 different shops. I can see the long 40 ft. shop in the end of my tractor barn painted now. The entire place is dirt except for the shop area. I have a cabinet and separate machine shop behind the tractor barn. I also have a shop here in California. I have a second hand store and I did not even put tile on the floor. I sealed the floor and set up the store. It is very nice. When I go to change use of the building or rent it out I will put in a good floor for the next business. They only need washing, polishing, buffing and take so much more work.

3 times washing a floor. ****** blazing saddles. I am a clean freek but 3 times. Really?
Your floor will continue to crack. You can fill it but I think the floor covering will fill it in just fine. It might open up more. You will get new cracks if you already have some. Any filling will show under the paint and look worse than the crack when you paint over it. You just have too much time on your hands. LOL

 

[bc_stang]

Um I think you are confusing epoxy coat with floor paint. I have worked in shops with epoxy coating and they are lot more durable than you think.

 

[LegacyIndustrial]

If you have hair line cracks in your floor you will only have more in the future. Just put a good sealer on the concrete and be done with it. I don't understand why people want to paint their floor. Unless you want a show room it is down right stupid in my opinion and I am a general contractor and architect. I also have a masters in art but I am an old farm boy and served a tool and die apprentice ship with GM and have worked for Boeing aircraft and the US Navy as an inspector.

Just because they make a product does not mean everything in the world should get painted with it. most of those floor paint were developed to paint basement floors.

While it looks nice it does not save the floor and only looks like hell when you start to work on it. The first time you pull your floor jack across it the nice finish is gone.

The problem is the cracking. You had a bad poor. If it has small cracks it is one of 3 things. The ground under the floor was not compressed properly. The concrete is to thin or it was a bad poor and was to wet when poured. You want to pour concrete as dry as you can and keep it wet after the poor for as long as you can. The longer it takes to dry the harder it gets. You can make concrete so hard you can not bust it up by hand. I have seen steps that I could not break and I am 6-1 and 270 pounds.

Just get a cement sealer and go to work and set up the garage. If I painted one of my shop floors people would think I had gone mad. I have 4 different shops. I can see the long 40 ft. shop in the end of my tractor barn painted now. The entire place is dirt except for the shop area. I have a cabinet and separate machine shop behind the tractor barn. I also have a shop here in California. I have a second hand store and I did not even put tile on the floor. I sealed the floor and set up the store. It is very nice. When I go to change use of the building or rent it out I will put in a good floor for the next business. They only need washing, polishing, buffing and take so much more work.

3 times washing a floor. ****** blazing saddles. I am a clean freek but 3 times. Really?
Your floor will continue to crack. You can fill it but I think the floor covering will fill it in just fine. It might open up more. You will get new cracks if you already have some. Any filling will show under the paint and look worse than the crack when you paint over it. You just have too much time on your hands. LOL

Sir you are off base. I have been working with floor coatings for over 20 years and early cracking is not a forecast for later cracking.

Lastly, some folks want or need a high impact, chemical resistant, attractive floor. Some are satisfied with less. To each his own.

 

[LegacyIndustrial]

Ok what do you guys recommend I should use to fill the cracks? I always thought since cracks are too thin, it will be easily covered up by the epoxy as it lays thicker then paint. Also since I am doing 2 coats, it should not be visible. Also legacy, what is bridging primer?

Bridging primer is a thicker, more flexible version of your standard 100 percent solids product. Useful over less stable concrete or even a wood substrate.

 

[bc_stang]

Bridging primer is a thicker, more flexible version of your standard 100 percent solids product. Useful over less stable concrete or even a wood substrate.

Ok thanks legacy. Do you carry it and how much is it for 24x25 garage? I am located in Vancouver,Canada so would also need it shipped to Blaine,WA ... Unless I can find it locally around here.

 

[LegacyIndustrial]

Ok thanks legacy. Do you carry it and how much is it for 24x25 garage? I am located in Vancouver,Canada so would also need it shipped to Blaine,WA ... Unless I can find it locally around here.

Link:

http://legacyindustrial.net/cart/flexible-epoxy-primer-hd139-2-gal-p-105.html

Figure, 90-100 sq ft. per gallon.

(3) or (4) 2 gal kits. of product.

 

[pauls_workshop]

BC, You will want to fill the cracks, any voids, and any holes or chips, but you can use several products to do that. I had some cracks and voids and just used a $20 rustoleum 100% solids patch kit. You can also just use some of your epoxy for the main coat if you have a good 100% solids epoxy there and some extra. Mix 4 to 1 white silica sand to the epoxy to stretch it. Overfill just slightly, then grind it off when dry. Then go over one more time without the sand, as a paper thin skim coat without grinding and the crack will be completely hidden by the top layer of epoxy basecoat then. - Paul