I painted my garage floor with Rustoleum EpoxyShield Garage Floor Coating in the summer of 2010. The floor was 20 to 25 years old by then and it was still bare concrete. I live in Wisconsin so the floor had been exposed to salt and melting snow as well as auto fluids. It was pitted in some areas but overall the floor was not too bad. I etched the floor with muriatic acid as prep and I tried to rinse it very well. I used a pressure washer and went over the surface multiple times.
After the first winter I started getting some spots where the epoxy peeled. I noticed that in those spots there is usually a white crystalline substance. The peeling almost always happens during or after the winter season. I pressure wash the floor in the spring and there are boundaries to these spots where the epoxy holds pretty well. However, each year there are more spots and it is getting to where I think it needs to be repaired or redone. I've attached a link below to some photos so you can see what I'm talking about.
I'm a real amateur with this sort of thing, only doing the floor that once. However, we once did a basement floor and didn't have any problems such as this.
So, my questions run the gamut. Here are a few:
1. What do you think causes the peeling and what is the white substance? Is it salt from the 20 winters with no coating? Is it muriatic acid that I didn't clean away properly? I'm posting a picture of what I scraped off one of the new spots with just my finger. It feels soft, like it's a white mold. However, sometimes, just by the look of it, I think it seems more salt like.
2. Do you think I can use a concrete sander around the existing spots and just spot paint the floor? Will that look OK? Or should I mostly sand the spotty areas and lightly sand the whole floor and paint it all again?
3. Do you have any other ideas or a process that I can follow to repair this? Do you have first hand experience with something that worked for you?
Here are some photos. The first photo is some of the white substance scraped onto a thin piece of cardboard.
Any advice will be appreciated.
Thanks!
https://goo.gl/photos/9acVW9y7wgakcmmN9
After the first winter I started getting some spots where the epoxy peeled. I noticed that in those spots there is usually a white crystalline substance. The peeling almost always happens during or after the winter season. I pressure wash the floor in the spring and there are boundaries to these spots where the epoxy holds pretty well. However, each year there are more spots and it is getting to where I think it needs to be repaired or redone. I've attached a link below to some photos so you can see what I'm talking about.
I'm a real amateur with this sort of thing, only doing the floor that once. However, we once did a basement floor and didn't have any problems such as this.
So, my questions run the gamut. Here are a few:
1. What do you think causes the peeling and what is the white substance? Is it salt from the 20 winters with no coating? Is it muriatic acid that I didn't clean away properly? I'm posting a picture of what I scraped off one of the new spots with just my finger. It feels soft, like it's a white mold. However, sometimes, just by the look of it, I think it seems more salt like.
2. Do you think I can use a concrete sander around the existing spots and just spot paint the floor? Will that look OK? Or should I mostly sand the spotty areas and lightly sand the whole floor and paint it all again?
3. Do you have any other ideas or a process that I can follow to repair this? Do you have first hand experience with something that worked for you?
Here are some photos. The first photo is some of the white substance scraped onto a thin piece of cardboard.
Any advice will be appreciated.
Thanks!
https://goo.gl/photos/9acVW9y7wgakcmmN9