Garage floor, repair or replace concrete?

[duns]

Hi folks.

Have a concrete garage floor that's showing signs of age in need of attention. Been putting it off for a while.

Garage is used to park a car, and will continue to do so.

As the pics show, floor is a little broken in places, has been patched here and there, surface crumbling, chips breaking off and a fair bit of dust now being created. Surface wasn't sealed or painted when laid afaik.

My aim is to raise the floor a couple of inches to help stop rainwater blowing in through the bottom of the garage door.

My question:
Is it ok to just add a 60mm layer of concrete/cement (or whatever material best) to this existing floor, seal/paint it, and hope it won't crack and break with the weight of a family car...
Or to remove this existing floor completely, install rebar and relay it from scratch?

I know it's always going to be better to re-do the whole thing, but I'm wondering how viable a cheaper quicker fix of a 60mm top layer will be. What material would be best suited, how long might it last, would it take a car coming and going over it daily etc.

Have had some advice that a screed layer of 4:1 sharp sand / cement mix at 60mm deep would be fine. Does this sound about right?

I wouldn't be too bothered about the whole thing, but it's just getting worse with time.

Thanks.

 

[Tigercubrider]

It looks as if there is a fair slope at the front, so height isn't really an issue.
I would be tempted to cut a channel across the width of the front, to divert water away from the door

You can buy garage door seals to stop ingress

Unless you need a perfect floor, I'd give it the heck of a sweep then use garage floor paint

 

[duns]

There's a ramp that runs up into the garage, the floor itself is level. There was a cemented ridge put in (not by me!) at the front to stop water ingress under the door, but as the first pic shows it's mostly missing now.

Would a self levelling floor screed compound be ok? Would it be strong enough to withstand the wear of a vehicle.

I'd like the finish to be smooth, ideally. Smooth and strong enough that if I'm working on a car, it'll take floor jacks etc.

 

[tomfe]

You can get self leveler which can be used as a wear surface, its used on wearhouse floors etc.
Normal stuff is not strong enough.
You could also epoxy it or grind a new surface.