How to level a floor with concrete

How to level a floor with concrete

Do you have a concrete slab indoors or outdoors that is not level? Or maybe looking for general knowledge how to level a floor with concrete?

Usually, small uneven parts of the floor aren’t done with concrete, but by using floor leveling compound over concrete. There is a guide on how to use floor leveler on the link.

Now, most of the floor leveling compounds are supposed to be used from only 1/8 inch to 1 inch and that is depending on the product. If you have 1-inch differences on your floor, it might take lots of self-leveling compounds to fix the whole floor and it might not be sensible to do.

Now there isn’t exactly a self-leveling concrete product, sometimes people use it as a synonym to floor leveling compounds, but concrete shouldn’t be that flowing and it has rough aggregates that would usually make it hard to do thin fixes.

The best self-leveling concrete product is the one that can get the job done with wanted strength and with hopefully the lowest possible cost. If it’s 1/8 inch to 1 inch, it might be the self-leveling compound, but for floors that are more uneven, let us go forward.

How to level uneven concrete floor

Now, we will close self leveling compound from our uneven concrete floor solutions as it’s gone through in the other guide.

Also, if the slab has sunken or there may be another kind of structural problem, read this guide on mudjacking vs polyjacking and also refer to local professionals for opinion. If you know it’s uneven because of maybe bad concrete pour, read ahead.

Now, to save writing space, I’m assuming all the concrete slab surfaces are ground and clean of dust by vacuum or water.

How to level a floor with self leveling concrete

How to fix uneven concrete garage floor

Garage floors are something that might be done with less attention than other indoor rooms. Or maybe your garage isn’t even part of the main house like mine isn’t. Or if the slab was poured too low for some reason or you want to install floor heating, this might be the solution.

If you want to know how to level a garage floor with concrete, let us assume you have over 1-inch differences in your garage floors. Pouring 1 inch of concrete isn’t that good idea as it is not that strong layer so you should go for 2 inches like they do when they do stamped concrete on top of the old slab.

Step 1: You need to set the height level all around the room so something like laser level is really handy. You can rent one or buy one, even the cheap ones will usually do for small jobs.

Step 2: After that, depending on the room size, you need screed boards on the side or to divide the floor to a manageable size. You have marked the wall height on the sides so it’s good to attach the boards there. If you need to install it in the middle, you can use a laser or string to have it at the correct height.

Step 3: After you’re done installing the screed boards, you make the concrete, pour it, vibrate it, and level the garage floor with wood board screed or proper metal screed, and finally float it. There is a DIY pouring guide on the link for more details.

If there is only small uneven spots on the floor, read the patio guide for another option.

How to level uneven concrete patio

An uneven concrete patio is another problem that you might have. It can be fixed like the garage floor and stamped to give it a new look or you could fix it like I’ve been doing with balconies that have problems with water control.

To fix them, there are also polymer cement-based leveling compounds that are not self-leveling. Balconies are usually sloped towards the outside so the water gets out, but sometimes the installing job is a failure.

These products are meant for fixing uneven spots, usually in situations I described. You can use similar products indoors and outdoors to fix the uneven spots and self-leveling floor compound on top of that as an alternative and finish with a coating like epoxy.

How to level low spots on a concrete patio

Step 1: If your patio is flat, but water gathers in the middle of it and makes annoying puddles, you can pour some water on it and mark those spots with a marker.

Step 2: Now that you know the spots, you make some floor compound and pour it on those spots, and use something to screed them level with the rest of the floor. Float the edges of the patch so they are level.

Step 3: Now for inexpensive ways to cover concrete patio there are resurfacing or self-leveling compounds. You need to pick something or just grind the floor and coat it. For a perfect job, I’d use this step for the floor compound.

Step 4: Grinding the floor. If you did a good job, rough sandpaper will do. If not, you might need to use the stone to grind it a bit. After that vacuum, it clean or wash with a hose after 3 days. Follow manufacturer info on watering the floor.

Step 5: Coating of your choice or sealer.

Now, this method can be worked with the garage as well. I separated them as I wanted to give options. Depending on the intent with the floor job, this might be a cheaper option.

How to level a concrete floor that slopes

A sloped concrete slab might be unsightly and annoying if it’s sloped too much. Again, if it’s poured like this it’s something we can fix. If it’s sunken with time, it’s time to consult experts about how to fix it or remove it.

How to level a sloping concrete patio

We can use a variation of the last part to fix this. We should have a long enough level to know how much we need to raise the other side of the slab or the laser level. A laser level is really handy here as you can set it on the height of the higher end and use the board on the other end to match it.

If the slope is great, maybe use concrete. If it’s only a little, I’d use proper floor compound that can fix the height difference.

Step 1: Use before mentioned methods to set the other end to same level with the other.

Step 2: Depending on patio type, you can even screw screeding boards to the sides so it will be level box around it.

Step 3: Pour concrete and screed the slab until it’s level and float it.

This was a simple fix for the problem. For how to level a sloping concrete garage floor I’d fix it in the same way, depending on the slope.

Some self leveling floor compounds could handle the floor, but if the slope is too big it would be another screeding board job.

Cheapest way to level concrete floor

Fixing a poorly sloped concrete floor for drainage or aesthetics can be annoying enough as it is. We most often want to do it as cheaply as possible.

If you’re not familiar with working with cement products, I’d say get a contractor. Here is guide for hiring one.

If you know your stuff, it’s the cheapest to DIY. Just look for the products available and see what they promise. Some research if they are good products and eliminating process is ready.

It’s also good to check why different products cost what they do. Maybe they are for special uses.


We should be more clear now how to level a floor with concrete and how to level exterior concrete slab that has different problems. Just remember when you think about how to level a concrete floor that slopes outside that sometimes it’s supposed to. That way the water goes away from the house.

To know how much it should check local building authorities. Usually, it’s something like 1/8 inch per running foot. Again, you don’t want the water under your house.

You can use self-leveling concrete outdoor like the floor compound, but those should be separated from the house like some patios are. That way the water will go around the patio and maybe it has its own drainage set there or you can slope it so the water drains properly.

The sloped concrete slab is a healthy slab outside as the water won’t be getting into rebar so quickly. Here is also a post about concrete floor textures if you want to try something new and a post about cement boards if you need to level other than concrete floors.