How to level a concrete floor that slopes – like a pro

When you notice that your windows and doors are sticking and that there are cracks in the floor of your home, the first question that comes to mind is How to level a concrete floor that slopes?

The words “quality,” “durability,” “endurance,” and “strength” certainly come to mind when you think about concrete floors. Concrete has long been the most popular material for laying a solid foundation. While all of these characteristics undoubtedly apply to a concrete floor, this is due to its exceptional strength and durability. Concrete structures have a long life expectancy. There are a few issues that you may encounter.

A poorly constructed concrete floor could exhibit a variety of defects, such as cracks, uneven surfaces, and even sloping slabs. In the case of a cracked floor, this is a more significant issue that requires professional attention. Imperfections are common in areas such as the garage, laundry room, basement, and landscape surrounding your home. A concrete surface subjected to excessive traffic or chemical degradation such as salt may crack, sink, heave, and slope over time.

Sloped concrete floors can be a difficult problem to solve. If you want to level the sloped concrete floor, it shouldn’t be a difficult task. Today, we’ll look at some of the possible causes and solutions to this issue.

When you notice a change in the gradient in your home, you might be wondering how to level a concrete floor that slopes.

What is the cause of the slope on your concrete floor?

Before offering any solutions or devising a strategy to address a problem, it is necessary to dig a little deeper and determine the root of the problem. This will not only aid in proper access to the problem, but it will also be the most important factor in a long-term solution.

While the problem may be with the concrete floor, more often than not, the root of the problem is with the house’s structure, whether it’s the foundation or the crawlspace. We’ll consider all of the factors and highlight the most common causes.

It’s important to remember that a sloping basement floor, or any other concrete floor for that matter, could be a one-off issue that leads to more serious problems. On the other hand, this problem could be a symptom of larger issues in your home.

Sloped Floor Symptoms and Signs

sloped Floor Symptoms and Signs - level a concrete floor that slopes

The main cause of sloped floors is foundation settlement. The home’s foundation settles unevenly as it sinks into a non-load-bearing stratum, putting uneven pressure on the home’s foundation.

The flooring bends, bows, and breaks as a result of the uneven pressure applied to the home’s wooden bones and the flooring. Floors can also sag due to age, wear, and tear.

Foundation settlement is frequently manifested by sloping floors. The following are a few examples of structural warning signs:

  • Crack foundation
  • Differential settlement of the foundation or slab 
  • Uneven bowed, ramped, flexed wooden floors.
  • Wall and ceiling cracks
  • Broken, chipped tile on tiled floors
  • Leaning walls (interior or exterior)
  • Doors and windows stick or do not open.
  • Leaning Chimneys
  • Cracked concrete slab
  • Cracks in drywall and stucco
  • Soil movement issues like slope creep
  • How much slope is there and where? Is it just a small area or is the entire house floor sloping?
  • Is it an old house or a newer house?
  • Does the slope appear to be getting worse over time, or has it stabilized?
  • The baseboard and crown moulding have large gaps and cracks.
  • A definite feeling of vertigo, uneven footing
  • Bouncy or trampoline floors.

The signs and symptoms of sloping floors are self-explanatory, and they’re usually good indicators that you’re dealing with either foundation issues or the normal wear and tear of an older home. These are just a few of the questions that may need to be answered in order to determine whether or not there is cause for concern.

The most common reason for sloping floor.

1. Foundation issues

Foundation issue - level a concrete floor that slopes

The issue with sloping concrete floors is usually the house’s foundation, not the floor. Who knows if it’s the cause? Aside from uneven floors, your home may have foundation issues.

The foundation is most likely faulty if the flooring sags towards the center of the house. Uneven floors can cause floor fractures and interior door jams to jam.

The crawl space is affected by a faulty house foundation. Mold or rotting in the crawl space indicates a foundation problem, which is a serious problem.

Why is this the case? This is due to the possibility of the foundation shifting or settling. Soil problems can cause masonry foundations to fail, which is extremely dangerous.

A faulty crawl space foundation can also cause a concrete floor problem. When a crawl space sags towards the ground, moisture is trapped, attracting pests and mold.

2. Issues with Crawl Space

A sloping garage floor, or any concrete floor for that matter, is likely to have a poorly built or damaged crawl area. If you can’t figure out what’s wrong, there could be other factors at play.

Jammed doors, wall fissures, and obvious gaps between walls, doors, and the floor below are all signs of a crawl space problem. A crawl space inspection is required in any of these situations.

Is it possible to repair a crawl space? Yes, but we always recommend consulting a professional in such critical situations, especially if you’re new to DIY home repairs.

Crawl space jacks are commonly used to solve structural problems in crawl spaces. Crawl space jacks are adjustable steel supports that support and prevent sagging in the crawl space foundation.

This will help level a sloped concrete floor and keep moisture out of the crawl space, which can lead to mold and bugs.

Finally, we’ll talk about how soil quality affects the foundation, floors, crawl space, and other aspects of the quality of your home. Long-term repairs can be difficult if your home is built on poor soil.

Severe rain, leaks, and floods all necessitate appropriate, effective solutions. If nothing is done about it, water may seep deep into the soil beneath your concrete.

All of this water could erode the soil’s structure and stability, making it unfit to support the weight of the concrete. Uneven floors result from drooping and sinking concrete slabs.

Soil Expansion: When the concrete is placed under immense pressure, floor cracks may arise. Once the soil has groundwater inside, it will push against and cause cracks in the foundation walls.

It’s also possible that the slob didn’t have enough room to emerge because the soil wasn’t spread out enough. The slab will begin to settle if the required grade level is not achieved, causing the concrete to slant or break.

In addition, if the soil is mostly clay, it will absorb water and expand, especially during the rainy season. It will shrink in size as it dries, affecting the concrete slab.

Soil shrinkage: If your foundation begins to dry out, the soil that surrounds it may shrink. As a result of the lack of support, the foundation walls begin to shift or move.

Heaving: During thawing or freezing, the ground can expand or heave. The floor will shift, move, or crack as a result of this expansion. It’s possible that more structural damage will occur.

Dos and Don’ts in Basic Repairs

Do not use a self-leveler until you have had your foundation inspected by a professional (if you self-level before your foundation is lifted to maximum practical recovery, you will have some wonky floors).

Note: We’ve seen homeowners use carjacks to pop floors back into place temporarily until foundation professionals arrive, but this isn’t a long-term solution.

Detecting the Seriousness of a Sloped Floor


What is the slope of your floor? If you want a correctly concrete floor level, you must now determine the exact slope measurement variations. If your home has a slope of fewer than 2 degrees (a 1/4-inch gap per foot), you may not need to do anything. Is it 1/4 inch sloping over 10 feet or 20 feet? In general, the higher the degree of slope, the higher the maintenance requirements.

If this is the case, but you have no other obvious problems in your home, the slope may not be as serious as you think. If the sloping is 2 inches in 20 feet, it is a serious concern, as it could be the result of shifting soil caused by a sewer leak or a water line break, and you should investigate it.

How to level a sloping concrete floor?

We can move on to actual solutions to this problem now that we’ve identified all of the possible causes and contributors to concrete floor sloping. Larger core issues, such as faulty foundations or crawl spaces, will, of course, necessitate a lot more time and effort.

We strongly advise hiring a professional to inspect the foundation and crawl space in order to access the core issues we’ve discussed. In this guide, we’ll concentrate on sloping floors and the best ways to level uneven concrete floors.

Find the source of the problem.

As previously stated, it is critical to identify the root cause of the problem and take action to address it. Otherwise, you’ll only be finding a band-aid solution, and it’s very likely that the problem will resurface sooner than you think.

Whether it’s a problem with the foundation, crawl space, soil, or the concrete slab itself, it’s always best to address the bigger issue first before attempting to level uneven concrete floors.

Make a plan of action.

Before starting any home improvement project, especially one as large as repairing concrete floors, make sure you plan ahead and figure out the best strategy. Budgeting and gathering all necessary tools and materials are also part of the strategy.

If you’re not familiar with concrete repair, or any other home repair project for that matter, we strongly advise you to seek professional assistance. It’s also important to figure out and assess the extent of the damage to your floors.

Collect your materials and tools.

The first thing you’ll need to do is gather all of the materials you’ll need to finish this project.

  • The concrete floor cleaner
  • Cleaning Brush
  • Drying Rags
  • Concrete Grinder
  • Vacuum Cleaner
  • Wooden planks
  • Eye glasses
  • gloves
  • Hard-bristled floor scrubbing brush
  • A concrete paintbrush or nap roller
  • Hand mixer, self-leveling compound, 
  • Bubble level (or even a line laser level)
  • Squeegee
  • High-pressure water hose
  • Protective Mask

Take the time to plan ahead.

It’s important to remember that while you could always level things off yourself by removing a large amount of material, this will be difficult and expensive.

As a result, you should really assess the situation first, particularly the current concrete floor’s condition and the slope’s degree. Most of the time, grinding down the high area points and then using a special self-leveling agent will suffice to fix the problem.

You simply need to assess the situation in order to determine how much material you will require to complete this task.

But what if your house is more than a decade old? Older houses necessitate extra attention. There could be cracks or dents in the concrete. Because concrete floors and walls are inextricably linked, a leveling error could result in structural damage to your home, which you don’t want!

Obtaining materials and determining the cause of your floor’s slope are all part of the planning process. As concrete ages, floor slopes can form. Due to normal wear and tear, water damage may necessitate more than just leveling your sloped concrete floor.

How much time do you think you’ll need?

The planning for concrete floor leveling takes about two days. because there are so many drastic differences between floors. Sloped concrete slabs do not all develop in the same way.

You can finish leveling your sloped concrete floor in 24 hours, but you’ll need extra fans to get the concrete completely dry.

Leveling takes about two days due to the bonding agent and compound. Prepare to store your large items until the levelling is completed.

Clean the entire area and remove large appliances from the floor.

How-to-clean-a-concrete-floor - level a concrete floor that slopes

Before beginning any work, remove all objects from your floors, including furniture, carpeting, rugs, and appliances. This will allow you to thoroughly inspect the floors for additional cracks or sloping.

Make sure the area where you’ll be grinding is clean. It’s critical to prepare the old, uneven concrete. If you don’t clean and clear the area where you’ll be working, you risk damaging the concrete and reducing the chances of the old and new concrete bonding together.

Because you want to create a nice base for the material you’ll use to level the floors, you’ll need to use a good concrete floor cleaner. You’ll need a special chemical cleaner, eye protection goggles, gloves, and a large cleaning brush to clean the area. Scrub the old, uneven concrete for about 15 minutes with the chemical cleaner. You’ll also have to clean and scrub the surrounding areas.

Clean floor with high pressure pump

After you’ve finished cleaning, use a high-pressure water hose to blast the dirt and debris away. If you have access to a pressure washer, that should suffice! Make certain that there are no small or large pieces left over. If there is still dirt and debris on the surface, the concrete bonding agent’s effectiveness may be compromised.

Make a mark on the area that requires consideration.

Now that you have a clean concrete floor to work with, it’s time to find the trouble spots. Make a note of each and every one of them so you know exactly what needs to be repaired.

To level your floor, you must first determine where the uneven areas are. Using tennis or golf balls, or any other round object that can roll is one of the simplest and cheapest ways to do this. Place the ball in various locations across the sloped floor.

ball slope level test

You can also use a level bar to check the level of your concrete floor and find any areas that stick out if they aren’t visible. Place the level bar on the floor and drag it across to see if there are any high points that indicate sloping.

Here, you’ll want to make a note of the high area points. You don’t need to mark the lowest points because they will be taken care of when the high points are ground away in the next step.

Allow it to dry before applying the concrete bonding agent.

concrete bonding agent

After that, go to your local hardware store and buy a concrete bonding agent, then follow the instructions. To make a liquid, you usually have to combine several ingredients. The thin liquid is required to form an adhesive concrete bond between the old concrete and the new self-leveling compound.

When the mixture is ready, roll the concrete bonding agent evenly across the floor with a paint roller. Because the toxins and fumes can cause complications, experts recommend wearing a face mask and goggles during this step. Avoid touching the concrete or bonding mixture with your hands, as this can cause rashes and allergic reactions. After that, the concrete bonding agent must dry to a point where it is no longer wet but still sticky, and you must take precautions. It should, however, be sticky enough to work with the concrete.

Get your self concrete leveling compound ready.

Spread Compound agent on floor

Now you must prepare the self-leveling concrete agent according to the manufacturer’s instructions. You’ll need to pay close attention to the self-leveling compound you choose after it’s been prepared, just like the special concrete bonding agent. These compounds usually necessitate the use of water, which mixes well with the self-leveling powder.

This self-leveling compound has a consistency similar to that of concrete. The texture, on the other hand, is smoother and serves a different purpose. Using a large electric mixer or a wooden stick, mix the solution.

Note: If you have an old uneven floor, you should inspect it for any “invisible” cracks. Although the cracks may not be visible on top of the concrete, there may be dips and vulnerable areas with water damage.

Use the Self-Leveling Compound to make the surface more level.

When the self-leveling mixture is finished, use the squeegee to move it around the ground, focusing on the unleveled areas. Your mixture should be thick and smell strong. You should keep your mask on until you are in a well-ventilated open area.

Spread it out all over the floor with a long-handled squeegee, making sure to get through all of the walls’ edges. Because self concrete leveling compounds like this dry quickly, be sure to work quickly.

A 1/4-inch layer of the self-leveling compound should apply to the floor. The self concrete leveling compound will indeed level itself, with the majority of it sinking into the lowest points and thus automatically leveling the floor without your assistance. All you have to do now is wait for it to dry completely, and you can always add more layers later if you want.

The process of set time takes about 15 minutes, but keep in mind that you won’t be able to return to the room or put your belongings back until the concrete floor is completely dry.

Let the compound dry before making any changes to the floor.

Smooth the mixture until it’s the same thickness all over. Smooth out any wrinkles or air bubbles with a wooden light board. A roller can also be used to ensure that the mixture is evenly distributed. Do not touch the concrete flooring for 24 hours or as directed by the self concrete leveling compound.

After it dries, it’s up to you to decide what to do with it! After the self concrete leveling compound has dried, paint, tile, or laminate over it to add color. Self-leveling compounds may not be available in your area, so you need to ask any reputable contractor to specify the appropriate self-leveling compound.

Installing laminate or tile, on the other hand, necessitates the use of mortar. If you’re going to tile or laminate over the repair, you should probably finish it first. Any lumps or gaps in the leveling can make it appear as if the laminate or tile isn’t level. Before moving furniture, open a window to let fresh air in.

Tips and Tricks to Avoid Mistakes

While the above should suffice, here are a few more pointers to help you get through the process more smoothly:

  • If you’re working on a large concrete floor, you’ll want to use a walk-behind concrete grinder to grind down the high spots. If you’re working on a small floor, such as one in a closet or a bathroom, you can use a smaller handheld grinder with a diamond disc to grind down the high spots.
  • When working with concrete bonding agents and self-leveling agents, always use gloves and the proper protective equipment because they can be quite corrosive.
  • Do not pour the substances onto the concrete without first cleaning and levelling it, as this will result in a disastrous outcome.


Overall, leveling and repairing a slanted concrete floor necessitates time, commitment, planning, and patience. Because a board on top of the concrete can warp due to moisture and temperature change, you may need to repair and patch the concrete again in the future. Although there are less expensive and faster ways to complete this task, they may cause more harm than good.

Concrete floors must be handled with extreme caution because they are typically connected to the building’s overall framework. If you patch a large area but it still sags, the floor beneath the building may shift and crack, causing more problems.

Frequently asked questions

Although this is a good way to level a floor that slopes, there are other options that can help balance the concrete floor.

How do you level an old uneven concrete floor?

Old and uneven concrete floors are complicated. When leveling an old and uneven floor, experts recommend using a self-leveling concrete compound over the old, uneven concrete or using wooden stakes as a base to hold the concrete in place.
Old houses and concrete floors require special care. Consider the home’s structure before determining how to level a concrete floor that slopes. Your home may collapse due to a simple oversight.

What is the cheapest way to level a concrete floor that slopes?

There are several inexpensive ways to level uneven concrete floors. Remember that cheap and affordable options are not always the safest or most durable. To save money, simply level the concrete floor with a self-leveling coating. If you buy a light and thin self-leveling compound, it may take several coats to finish the floor.
This coating concrete can be applied only to concrete cracks and tears. It may not completely level the floor. It’s a temporary fix that may be concealing a major issue. Another way to reduce the cost of leveling a concrete floor is to only level a small area. If a concrete slab is out of place, only grind and use self-leveling concrete on it. This may cause future issues, but it will save you money on supplies.

Can you pour self-leveling concrete over existing concrete?

Pouring self-leveling concrete over an uneven concrete floor is a simple solution. Experts advise first cleaning and buffing the old and uneven concrete.
If left behind, large concrete rocks and debris can cause major issues. Once poured, self-leveling concrete cannot be removed. If there are interruptions, the adhesive and self-leveling concrete may not work. Concrete needs a solid foundation.