Re-surfacing an old concrete garage floor

[p.dath]

The concrete slab in my father in-laws garage is quite old and showing it. The concrete surface has substantially broken down with pitting and cracking. There are two small areas that are perhaps 15mm deep. The underlying concrete itself seems in good stable condition. It's only the surface that is in a sad state.

I don't know anything about concrete. I have talked to a few people about options, but they don't really make me feel confident with their advice.

At this stage, I am thinking of getting some concrete grout (like Sika 212), and spreading a thin layer over most of the floor to bring it back to being a nice smooth well formed surface. I'm thinking of using cement based grout because it will stick to the existing concrete. I want something that will be happy with a couple of tonne of car driving in and out on it.

So will cement grout do the job?

[unstuck]

So will cement grout do the job?

IMO no. Is there enough left to grind and polish?

[p.dath]

IMO no. Is there enough left to grind and polish?

The problem is the two bad areas are about 15mm deep. Grinding the whole floor down 15mm would be a big job. Plus I would have to do something about the interface between the drive way and the garage floor with a difference that big.

[unstuck]

How about building it up a couple of inches? Thin layers over the top of old concrete seem to crack fairly quickly.

[rickstv]

I saw a garage floor tiled to cover up imperfections in the concrete floor surface. seemed to work for them ok and looked real good too.

And another job I came across the guy got lino laid on the garage floor.

Rick.

[willytheekid]

You can get that heavy duty "rubber grit" paint that they use on some Ute decks

acts as a sealant, its petrolium proof, grippy and slightly rubbery so it takes impacts from tools etc well, build up the 15mm holes etc to get a smoothish surface, then slop a couple of thick coats on...stuff's not that cheap tho, but theres so many paint type thick sealant products out there you should be able to find one that suits


...yes, I am a cheap bastard

[p.dath]

How about building it up a couple of inches? Thin layers over the top of old concrete seem to crack fairly quickly.

That's the trick - what to build it up with.

I saw a garage floor tiled to cover up imperfections in the concrete floor surface. seemed to work for them ok and looked real good too.

And another job I came across the guy got lino laid on the garage floor.

Rick.

I did consider putting down some garage carpet, but with the underlying floor in such bad condition - it'll reflect on anything put on top of it.


I am also considering the option of trying to lay a wood floor over the top of everything, effectively a new floor. However I still have to deal with the issue of reforming where the drive way enters the garage due to the difference in height. So I would prefer to just re-surface the existing concrete if possible.

[unstuck]

How about grouting the holes and cracks, then using an epoxy finish? May or may not be as dear as using wood, timber prices being what they are . Or you could just build the whole lot up a couple of inches with a smooth concrete mix, but I think it would still end up cracking.
Any local concrete grinders in your area? You may be surprised how quickly and how deep they can grind. Dairy farmers use them a bit to grind down the shed floors.

[ellipsis]

There is no easy fix for your problem floor. Any solution will require a lot of preparation.
Any product used to skim the floor will be expensive, and always dependent on adhering to the prepping instructions that in the real world of concrete floors is difficult and time consuming.
Vinyl and carpet layers would use a product called, Floor Levelling Compound and then skim the lot, very thinly with a product (sorry dont know the name of product, but a call to a carpet/vinyl layer would sort that). This would only be done if carpeting or laying vinyl.
timg on here I believe has a business involving industrial type carpet for these situations. Maybe he could give some advice on that solution.

[p.dath]

How about grouting the holes and cracks, then using an epoxy finish? May or may not be as dear as using wood, timber prices being what they are . Or you could just build the whole lot up a couple of inches with a smooth concrete mix, but I think it would still end up cracking.
Any local concrete grinders in your area? You may be surprised how quickly and how deep they can grind. Dairy farmers use them a bit to grind down the shed floors.

Unfortunately concrete doesn't bond to concrete, so you can't just put another layer on top. If you put a thin layer on top, it is only as strong as that thin layer, and I think it would crack.

There is no easy fix for your problem floor. Any solution will require a lot of preparation.
Any product used to skim the floor will be expensive, and always dependent on adhering to the prepping instructions that in the real world of concrete floors is difficult and time consuming.
Vinyl and carpet layers would use a product called, Floor Levelling Compound and then skim the lot, very thinly with a product (sorry dont know the name of product, but a call to a carpet/vinyl layer would sort that). This would only be done if carpeting or laying vinyl.
timg on here I believe has a business involving industrial type carpet for these situations. Maybe he could give some advice on that solution.

I looked at using floor levelling compound first, but most only recommend a fill up to 3mm to 5mm, so you can't use it in a 15mm hole. Also I need something strong enough that a car can sit on (so much heavier load than a standard domestic floor for humans).

[TheDemonLord]

I have got a solution!

Get a bunch of really strong Ethiopians to hold about a 10 mm thick steel floor, Get them to angle it so that your dad drives in as normal, and then they place it gently on the floor.

Total cost is the cost of the steel and a years supply of Crisps.

[jonbuoy]

I filled the holes in the floor as best I could with some repair filler, cleaned the dust and any oil off then used a two pack epoxy garage floor paint. You will probably need three coats of it- first one will get absorbed. Cuts down on the dust levels massively. Don't use single pack paint - get the epoxy based gloss finish - same product they use in underground car parks.

[Akzle]

cemlevel 10.
Might need /want to acid wash first.
Honour saw cuts.
Paint with rubbery shit.

[Akzle]

ok. Read the thread.
Cemlevel will hit 3-30mm. You will want it at least +10 across the whole floor. Get a proper git in to screed fall in and float it flat.

[p.dath]

cemlevel 10.
Might need /want to acid wash first.
Honour saw cuts.
Paint with rubbery shit.

Thank you!!! I just read the spec sheet, and it sounds like it does exactly what I want.


I been trying to call the 0800 CEMIX technical support number but haven't been able to get them to even answer the phone. I went to two of their agents and they don't seem to know their own products very well at all.