Stains on concrete floor

[windymill]

hello,
I am struggling to cover paint stains on my garage concrete floor. Trouble is I don't know what they are. Previous owners ran a business from it, painting things, and there are lime yellow and dark blood red stains everywhere. Tried two coats of Zinnser Bin water based formula; so far still bleeding through, even when it's being applied. Don't know what else to use. The garage is going to be used as a workshop, not for cars.
Any advice appreciated, don't want to waste any more money buying wrong thing for the job.
Thank you.

 

[Grenage]

If water-based is bleeding through, what about oil-based?

 

[windymill]

I don't know, would that stop it? Thought they were same formula, just different clean up methods. Is there anything else? Thank you

 

[blightymam]

Thought they were same formula, just different clean up methods.

Completely different!

Oil based is a good idea, or try shellac based paint as an undercoat. Your BIN would've been a good idea if it hadn't been water based but the shellac one.

 

[misterhelpful]

As far as I know, there isn't such a product as water based B-I-N, just the shellac based version. Did you mean Bullseye 1-2-3?

Either way, neither would be recommended as a garage floor paint because, although they are both high adhesion primers, they will not hold up to constant wear and tear of foot traffic. You will need to find a good quality, 2 pack epoxy garage floor paint to do the job you require.

 

[windymill]

Hi, it was water based Zinnser. I've now used shellac formula. That has covered thank goodness, but although I've put another coat of floor paint, I've now got darker patches from where it's covered stains, and lighter ,spatchier on rest of concrete. Hmm! Do I now cover whole of floor with shellac? Misterhelpful, thank you, I've never heard of that so will check out. Floor is approx 35 ft X 25 ft. This could get very costly!

 

[misterhelpful]

B-I-N is notorious for flashing through your finish paint, which is probably the cause of those patches, and usually requires a couple of coats to cover properly.