Garage Floor Primer/undercoat

[jellybeard999]

I painted my garage floor a few years ago with a 2 0art epoxy paint and it's looking a bit shabby in parts, peeling or flaking a little. The majority seems fine and bonded to the concrete. The floor itself was previously unpainted and 50+ years old.

I'm planning to leave the good paint alone andgrind any loose areas back to bare concrete and want to prime those areas. I assume I'll need to overlap onto the paint slightly but most primers seem to be forbporous bare concrete. Is it OK to just paint over the solid paint?

Can anyone advise if my approach sounds correct and recommend a primer?

I have a polyurethane paint which I plan to repaint yhe whole garage in.

This is a job for next early really, but it's on my mind so trying to plan ahead a bit.

 

[Nasher]

Is the floor damp proof (as in a damp proof coarse)? A lot of garages aren't as it's not legally required like on a house. If not, no paint straight on to the floor is going to last.

 

[jellybeard999]

Is the floor damp proof (as in a damp proof coarse)? A lot of garages aren't as it's not legally required like on a house. If not, no paint straight on to the floor is going to last.

No idea. It's a 60s build so probably not.

I was thinking if priming the bare areas with SBR but unsure if that would be beneficial.

The majority of rthe floor is fine it's just certain smalll areas that are a bit flaky

 

[alexalwood]

Following on from Nasher's point about damp proofing, you can test the slab yourself. Tape a square of clear polythene, about 60cm across, down on all four sides and leave it 48 hours. Droplets underneath, or a dark patch on the concrete when you lift it, mean moisture is coming up through the floor.
Flaking epoxy on an old slab is often that. I run a water damage crew in Denver, so I can't speak for UK products. The test is the same anywhere.

 

[OpenToSuggestions]

I put Duramat tiles down on my new build garage floor ~18m ago and they look great.
My last house was also a new build and the paint I put down kept coming up, so it looked rubbish.

 

[Nasher]

Following on from Nasher's point about damp proofing, you can test the slab yourself. Tape a square of clear polythene, about 60cm across, down on all four sides and leave it 48 hours. Droplets underneath, or a dark patch on the concrete when you lift it, mean moisture is coming up through the floor.
Flaking epoxy on an old slab is often that. I run a water damage crew in Denver, so I can't speak for UK products. The test is the same anywhere.

You can often see it (on British houses at least). A few bricks above ground level, usually the edge of the membrane is visible in places.

I put Duramat tiles down on my new build garage floor ~18m ago and they look great.
My last house was also a new build and the paint I put down kept coming up, so it looked rubbish.

Problem with that is you'll get moisture building up under the tiles. It will slowly eat the concrete and stink :/