Fixing grade on concrete garage floor?

Question

Here is a concrete garage floor that has a pitch and/or concavities that cause water to puddle inside the garage in the middle of the slabs instead of draining out the front.

What are realistic solutions to prevent the puddling of water brought in by cars?

I don't think it would be effective to grind the cement because the adjacent driveway slab starts at the same level as the current garage slab, so grinding in the garage to create a pitch would just cause water to pool around the door.

I also inquired about mud-jacking but was told that can't be done for such large slabs.

Answer 1

The cheapest solution is to cut a weep path that runs from the pooling point out the door, as long as you start shallow and keep increasing the depth the water would flow out. Depending on what the drive way looks like if it is a hill that slopes down that might be all that is required. Possibly make a cross type design with cuts to direct the water from the area your tires normally sit to a middle cut line. I'd probably start with a 6' straight edge and find the lowest spots to mark them.

The more expensive solution is to get the garage epoxy people to do it for you. They'll grind the concrete for it to accept the epoxy coating and should be able to use self leveler to achieve a slope before doing the epoxy.

Answer 2

Whoever told you that mudjacking isn't done for large slabs was just misinformed, incompetent or very wrong. Mudjacking works exceptionally well on large slabs. You do have to get a competent company to do a good job. Locally, a huge floor was jacked up by Houck Construction. I believe it measured about 100' by 300'. I recommend MudJacking, or alternatively I recommend Sikadur 32 Hi-Mod as a very high-end bonding agent and a masonry skim coat to bring up the surface. There are plenty of how-to videos showing how to do the skim coat, or contract a good mason to do the job.