Concrete raising saves 50% of the costs in comparison to concrete replacement. It raises concrete slabs and proceeds to the filling of void spaces beneath them.
Polyurethane foam is hydrophobic, impervious to water and cures in one hour after its injection.
Repairing the existing concrete by injecting a mixture under the slab to raise it to its original position.
It’s possible to use a high-density polymer to lift, level, and stabilize your settled concrete slabs. The best part is that it is a quick, easy, and economical choice for your home.
Raising concrete with foam is a permanent solution that can save you money. Especially if you plan on selling your home and would like to instantly improve the look of your concrete. Continue reading for a guide to the complete process.
|Concrete Raising||Poly Foam||Mudjacking||Concrete Replacement|
|Completed in a few hours||Yes||Yes|
|No Disruption to Landscape||Yes||Yes||Depends on each project|
Reasons For Concrete Sinking
Although concrete is a fairly durable material, over time it can shift and sink with the ground beneath it. This is especially true for climates that have extreme season cycles.
Over time, your once pristine and level concrete can sink and crack. This can happen even quicker if the concrete was built over stone or soil that was not properly compacted.
Water is another major culprit. It penetrates through cracks in the surface and slowly erodes into the base material.
You may be avoiding having to repair your concrete for fear of the cost. However, if left unattended, sunken and cracked concrete can become dangerous tripping hazards or it can create other problems with your home when it causes water to pool.
If you are trying to sell your home, old concrete can lower its property value. Ultimately it is an eyesore that reduces your home’s curb appeal.
Concrete Raising With Foam
When it comes to fixing sunken concrete there are two options. The most obvious is to have the concrete replaced. However, there is a much more cost-effective option that you may not have heard of.
Polyurethane Foam is pumped under pressure into small holes drilled through existing concrete slabs. The slurry or foam displaces air pockets, water or water saturated materials, fills void areas under the slab, raises the slab, and leaves a firm permanent subgrade.
The process is similar to mudjacking but the results are longer lasting and less invasive. The system works by injecting high-density polymer below a sunken concrete slab, causing it to raise to its intended position while also stabilizing loose soil. The polymer is light weight and extremely strong which makes it a longer-lasting repair option when compared to traditional mudjacking.
Raising concrete with foam or a polyurethane product is very effective in fixing concrete. It not only extends the life of your concrete but also saves you time and money.
Plus, raising your concrete rather than replacing it will help you reduce your environmental footprint.
Unlike mudjacking, the results of using a PolyLifting system will last much longer. The polymer is lightweight but extremely strong which makes re-settling less likely. Making it an ideal alternative.
It also requires a lot less time. While mudjacking requires 24 hours after installation before it can be used, polyurethane is ready for use just 15 minutes after installation.
Concrete Raising Process
The polymer foam works by injecting it below the sunken concrete slab. This causes it to rise to its appropriate position. It also helps to stabilize loose soil. Once completed after just a few hours, the concrete can be used again shortly after it cures.
The final results are a smooth and level concrete surface. Only dime-sized holes are used to inject the polymer. So they are barely noticeable.
Want to know how it’s done? The entire process is quick and easy. Meaning you won’t have to disrupt your daily life to get it done. Let’s show you how simple it can be.
Visit from Professional Estimator
Before work begins a trained professional estimator will visit your property to take a look at your concrete. He or she will determine what’s causing the settlement. Measurements are also taken so that a cost estimate can be provided.
It begins with our trained professional estimator visiting the site, evaluating the possible cause for the settlement, taking measurements and then generating a detailed estimate. This can be done without needing to be home unless it’s an interior slab.
If it’s a concrete slab located outside, then you won’t even need to be home for the estimate to be done.
Once you’ve received the estimate and agree to the procedure, workers will arrive to drill small 5/8″ holes into the sunken slab. This is strategically done so as to avoid cracking and also to make sure the foam is injected in the appropriate places.
So let´s put it clear:
Once the crew arrives, small 5/8” dime size holes are strategically drilled into your sunken slab. Since the holes are so small, they are hardly noticed after completion and there is less chance of the slab cracking.
Injection Of The Foam Into The Cavity
The next step is to begin to inject a polymer liquid into each hole. Once inside the liquid turns into a foam and will expand to fill open voids and holes. This will quickly stabilize weak soil and also lift the sunken slab.
The technician now carefully injects a two part liquid polymer into each hole. The liquid turns into expanding foam once mixed below the slab, quickly filling open voids, stabilizing weak soil and lifting the slab.
Patching The Holes Drilled
After the polyurethane foam or the cement slurry, or any similar mixture is poured successfully into the drilled cavity, the service contractor will complete the concrete raising process filling the voids of the drills done at the beginning.
When the concrete slabs are fully leveled and stabilized it’s the technician’s turn to fill each small hole with grout. This ensures a tight seal that will last and protect your concrete.
Once all the concrete slabs have been fully leveled and stabilized, the technician fills each small hole with grout to ensure a long-lasting tight seal. Your concrete is now restored and the repair is hardly noticeable!
It takes about fifteen minutes for the poly foam to cure. Some mixtures can cure in up to an hour. However, in a short period of time after the concrete raising, the surface is ready to be utilized by pedestrians or automobiles.
Concrete Raising Pros And Cons
Customer Satisfaction – Cost! – The costs to raise or level concrete slabs are 50 to 75% LESS than the cost of concrete replacement.
Fast process: It is completed in a bit less than a working day. All materials are mixed on site and injected.
Waterproof: Expanding polyurethane foam is waterproof whereas traditional mudjacking material is not. This prevents future erosion and reduces the chance future settling.
Lightweight: Expanding polyurethane foam can uphold significant loads without adding unnecessary weight to already unstable soil conditions.
Immediate Use – In most cases, concrete repaired through concrete raising can be used almost immediately following the completion of the job. In contrast, new or replaced concrete has to cure for a minimum of 28 days.
Long-term Fix – Concrete slabs raised with our cementitious slurry or polyurethane foam can carry a warranty of up to 2 years. The length of warranty depends on soil conditions, drainage and other factors. The polyurethane material will not shrink, breakdown or wash-away like cement or mud-based materials can overtime.
Very Small Injection Holes Required: Since Polyurethane begin as a liquid, much smaller holes are needed (penny-sized) compared to mudjacking (golf ball sized)
No Disruption to Surrounding Landscape – No need to repair surrounding areas of grass, trees, and/or shrubbery as you would have to with concrete replacement.
Reduce Liability – Eliminate trip hazards, excessive step height, improper pitch of slabs.
No Environmental Impact – Green! – Landfill legislation in many parts of the country lists old concrete as Hazardous Waste, adding an additional recycling cost to those choosing to replace concrete (for both the operator and the customer).
Improves Curb Appeal: If the concrete raising is performed in a visible part of your property, such as a driveway or a sidewalk, it will clearly look much better. This is also an advantage of concrete replacement.
I could not find any disadvantage for the concrete raising process. It is much cheaper and faster than the alternative of concrete replacement. It also cures quicker and can maintain longer.
Concrete Raising Cost
Concrete raising is typically about half the cost of replacing the same concrete. Ultimately, the cost of raising or stabilizing concrete is a direct reflection of how much material the project will take. A simple project to raise a slab of concrete will cost less than, if there is a large void under the slab requiring more material. In general terms, concrete raising can cost between $2-$5 per square foot.
For example: a 10 ft. x 10 ft. section needs to be raise is 100 square feet. This job could cost between $200 and $500 to repair. Depending on how far the slab is settled, if there are voids present, or if other sections need to be involved in the repair, will determine where in the scale the job would be bid.
Raising concrete is an extremely affordable option when compared to replacement. Since every job is unique in terms of the amount of material needed and the size of the area being raised, giving an average cost is difficult.
In general, raising concrete with polyurethane is typically 50%-80% less than replacement. The size of the area and the amount it has sunk are the biggest factors that determine the price.
Fill a form to obtain FREE estimates, so a seasoned estimator can look at your project, and provide you with an accurate estimate of what it will cost to complete your specific project.
Mudjacking As A Variant Of Concrete Raising
In this technique of concrete raising, there is no polyurethane foam injection. I was recommending it until our 2022 update of this article. Since then, I consider that the poly foam injection is better for concrete raising.
In the past, mudjacking was the only method available for homeowners looking to lift and level their sunken concrete. Mudjacking, which works by pumping a cement and sand slurry below a slab to lift it back up. Mudjacking has been a popular method in the past however it was never regarded as a long-term solution since the slurry material tends to break down over time and the heavy weight of the material can cause the slab to re-settle again. It also required drilling large 1″-2″ holes into the concrete which didnt look too great and weakened the slab. To solve these issues polyurethane foam is now the preferred materiel to be used when lifting and stabilizing concrete.
An experienced mudjacking contractor knows how important it is to pump the proper thickness of mud slurry. Often, the thickness is changed several times when raising a slab correctly.
Some contractors have a transportable pumping device that is specifically envisaged for mudjacking.
With our shorter pump hose, we can change the thickness of our slurry much faster and more efficiently. Others are stuck with a lot of material in a long hose that could be the wrong thickness. Pumping the wrong thickness of slurry often leaves cavities under the slab and could even break the slab during concrete leveling.
Scope Of Work For Concrete Raising
Concrete raising or lifting, can be performed in any flooring concrete arrangement.
You can raise, level and stabilize sidewalks, curbs, gutters, streets, highways, parking lots, garage floors, patios, pool decks, industrial floors, bridge approaches, basketball courts.
In essence, most any residential, commercial/industrial, and/or municipal concrete slab on grade can be raised, levelled and stabilized.
Longevity Of Concrete Raising
Polyurethane since it’s a synthetic material, will not change shape or breakdown like other materials such as sand or cement. However, the ground can and will move overtime depending on soil conditions, especially with the frost cycles we experience here in the Midwest. Also, water intrusion from poor drainage can erode the soil, which can cause re-settling. Lastly, a long dry spell over the summer can cause the ground the shrink, which can impact your concrete. So typically if there is any re-settling it’s most likely due to soil conditions, poor drainage or extreme weather all of which would also affect new concrete.
Concrete Raising vs Replacement Of The Existing Concrete
Polyurethane injection (PolyLift) to be most effective alternative to replacement. Below are the reasons why concrete raising may be a better choice for repairing sunken concrete.
- Very Affordable: Raising concrete is normally around 50% to 70% less than having it replaced!
- Quick: Our raising process can be completed in 30-60minutes compared to days with replacement.
- Less Hassle: No need for permits, inspections, landscape restoration and all the noise, dust and other things that are part of the concrete construction.
- Green: If are trying to do your part to minimize your environmental footprint, then raising your concrete rather than replacing it is one way to do it.
Of course, not all concrete can be raised. Raising may not be a viable options when there is a large amount of cracking and/or surface wear.
Mudjacking vs Foam For Concrete Raising
there are a number of advantages to using polyurethane vs mudjacking to raise concrete in regards to appearance, longevity and process. Read below to learn why more and more homeowners and property managers are using polyurethane to raise and level their sunken concrete.
Both methods will certainly lift and level your concrete however there are many advantages to using polyurethane over mudjacking. Below are the main advantages and benefits to using polyurethane over mudjacking:
Smaller Injection Holes: A key benefit many property owners love about using polyurethane to repair concrete compared to mudjacking are the smaller holes that are required. Our polyurethane method only requires 5/8” holes (the size of a penny) compared to 1”-2” size holes needed for mudjacking. Our process produces a nearly invisible end result. This is especially important when repairing decorative stamped concrete.
Fewer Holes: Our polyurethane foam needs fewer holes to be drilled in your concrete for a cleaner look compared to mudjacking. Because polyurethane foam is sprayed below the slab as a highly pressurized liquid, we can cover a larger area from each injection port. The foam can flow and expand from 4 to 15 feet from each injection port. Since mudjacking uses a heavy slurry, only 1-2 feet can be covered below the slab from each hole. This means more holes are needed to raise and level concrete when using mudjacking. Those who prefer their concrete to not look like Swiss cheese after it’s raised prefer using the polyurethane method.
Longevity Of Foam Injection vs Mudjacking
Lightweight: Mudjacking uses a grout made of sand, cement, and water. On average this can weight around 100lbs per cubic foot. This heavy material can put more burden on an already weak base which can cause future settling to occur. Polyurethane on the other hand only weighs 2lbs per cubic foot. Which means our lightweight material will put much less (about 50 times less!) weight on your base which decreases the chance of future settling when compared to mudjacking.
Non-Shrinking Material: polyurethane material is made from environmentally safe materials and becomes an inert, high-density solid material minutes after it’s injected and will forever keep its shape and strength. Mudjacking, on the other hand, is made from water, sand, and cement, which means it can shrink, wash away and can be susceptible to moisture and erosion.
Cleaner: Our material is contained in our specialized trailer, it is then pumped to each injection port through a hose. That’s it! Unlike mud jacking, there is no need for heavy equipment to be used on your property and messy grout spills to be cleaned. Also, since our holes are so small, there is less dust created compared to mudjacking. Of course, any dust that we do create is quickly vacuumed up!
Faster: Once the polyurethane is pumped in it only needs 15 minutes to cure before it’s ready for cars to drive over the concrete. No need to wait days to get your car back in your garage, which is the case with mudjacking. Business owners can also allow customers and employees to use the area immediately after we leave. A much cleaner process and the area is usable 15 minutes after installation vs 24 hours with mudjacking
Contractors who argue that mudjacking is the best method are either misinformed or are just reluctant to update their equipment and process.
Concrete Sinking Again After The Raising
The great thing about using a polyurethane foam is that it’s a synthetic material that will not breakdown or change shape.
Since polyurethane is extremely lighter than mudjacking material the chance of re-settling is greatly reduced.
That reduces the likelihood of your concrete sinking at the same rate.
However, just like new concrete, changes in soil conditions can happen due to frost cycles, poor drainage, or erosion. This can cause your concrete to sink over time.
The key to preventing concrete from sinking is by filling voids and keeping water away. Open voids below your concrete should be stabilized with polyurethane foam. All open gaps such as cracks and expansion joints should be caulked to stop water from getting below the slab and eroding the base. Also, all water should be directed away from your concrete such as downspout. The sides of your concrete should also be properly graded so that the base cant wash away.
The best way to prevent your concrete from sinking once it’s treated with foam is to keep water away. This can be done by redirecting water using a downspout. You should also grade the sides of your concrete properly so that the base can’t wash away.
Continue to maintain your concrete for longer by filling voids with polyurethane foam. You should also make sure gaps and expansion joints are caulked to stop water from getting beneath the slab.
Hello, I am Marcio. I am an architect and designer, alma mater is Mackenzie. Retired in theory, but an architect never retires completely. Along with architectural projects, I am a filmmaker and have completed some short documentaries. Filmmaking and design are my passions. In HomeQN I write about home decoration and foundations. The goal is to teach homeowners to DYI as much as possible, and when this is not possible, enable them through knowledge, to evaluate service quotations and choose the best service technicians.