What is Concrete Lifting?
Concrete lifting is a process that goes by many different names – most commonly mudjacking or slabjacking (or simply concrete lifting). As the name suggests, concrete lifting involves raising up a slab of concrete that has subsided. For example, if your driveway has begun to sink into the mud and soil underneath (which is usually indicated by poor drainage, cracking, or unevenness), then you will need to lift the entire slab from underneath.
The process is extremely simple, involving pumping concrete underneath the slab. There are some variations on the technique depending on the specific circumstances around (and underneath) the slab.
If you have a concrete slab that has subsided – including the foundation of your home – concrete lifting can be the difference between a $1,000 repair bill and one running into the hundreds of thousands. This guide will discuss all the different aspects of concrete lifting you need to know, so you can decide if it’s the right option for you.
HOW DOES THE PROCESS OF CONCRETE LIFTING WORK?
Concrete lifting is a very simple process – albeit a process that requires professionals with a great deal of expertise to get right. To successfully lift a concrete slab, you first drill small holes into the slab. These holes can either be where the slab needs to be lifted or, in the case of extreme subsidence, across the slab as a whole. This process requires professional tools since it requires extremely small holes to be drilled through an extremely solid surface (without cracking it).
Once this has been done, a pump is attached, and concrete slurry is pumped into the holes at extreme pressure. The concrete slurry flows through the holes and into the ground underneath. This has two key functions.
The first of these
is to add fluid underneath the required part of the slab. The additional pressure of the fluid helps to raise up the concrete slab and ensure it stays raised.
The second function
of the concrete slurry is to stabilize the material that the slab rests on. For example, if the slab has subsided because of being placed on waterlogged soil, the concrete slurry will solidify the ground and prevent any future subsiding.
Concrete lifting is, therefore, a relatively unobtrusive process, a relatively quick process, and one that has permanent benefits. Because of these three main factors, it is becoming an ever more common way of fixing concrete slab sinking problems. Additional benefits have come from technological advances and lower prices.
When is concrete lifting the right option?
There are several circumstances in which concrete lifting is the right option for you. Generally, if you have a concrete slab that is sinking or subsiding, concrete lifting will work. The only situation in which it doesn’t is when the concrete is too badly damaged – maybe there are extensive cracks or the concrete has been crushed. However, if the structure of the concrete is sound, you should be able to use concrete lifting to solve your problem.
The most common uses of concrete lifting are the following:
If you have a walkway in your yard, you’ll know that cracking is extremely common. Lifting the concrete is the best way of preventing further damage.
Because patios are often built on soil, any issues with drainage create uneven amounts of mud underneath. Shoring this up with concrete slurry will not only lift the patio but will prevent further sinking.
Pool decks also commonly crack due to unstable soil underneath. This can be not only dangerous but also unsightly.
Sagging parking lots or driveways
The sheer weight of cars or trucks moving around a parking lot or driveway can cause even 6-inch thick slabs to sink over time. Lifting it up is often the only long-term solution.
If the foundations of your home are sinking, it can mean extremely bad news. This can ultimately result in your home becoming unlivable. The sooner you treat a sinking foundation slab, the better for the home and the cheaper for your wallet.
What are the benefits of concrete lifting?
Some of the benefits of concrete lifting have been discussed above. However, there are three main areas in which it has major benefits over other types of repair.
Price is arguably the primary advantage that concrete lifting has over other types of concrete repair. The costs will be discussed in the section below, but the alternative to concrete lifting tends to be slab replacement. Slab replacement will likely cost you twice as much as concrete lifting (and three times more in some cases).
Repairs that result from concrete lifting are invisible and don’t leave any unsightly marks on the concrete. The holes that are drilled are filled in and caulked and are invisible to all but the closest inspection. By contrast, if you were to cut out the sunken piece and add in a new bit of concrete, it would be unlikely to match the exact color of the surrounding areas. Concrete lifting, therefore, is a far superficially preferential option.
Speed and ease
Concrete lifting allows you to keep your existing slab in place and usually takes only an hour or two. The noise and dust are minimal, and you only need to wait a few hours for the concrete to dry before putting heavy weight on it. By contrast, a new slab can take days to fully dry and can be used as normal.
In addition, there are new technological innovations that constantly improve the process of concrete lifting. For example, the slurry that is pumped under the slab is becoming increasingly more environmentally friendly and cheaper to produce, helping to drive costs down even further. In addition, there are concrete substitutes that can be even stronger and long-lasting.
What are the drawbacks of concrete lifting?
To be very clear, the benefits of concrete lifting outweigh the negatives. You should also consider the fact that there is often no perfect solution – it’s a case of making the best possible decision given the information available. Finally, you should remember that concrete lifting is often preferable when compared with alternative courses of action. However, it is worth thinking about the potential limitations of concrete lifting.
The first of these is that it may not always address the root cause of the problem. Although concrete lifting returns the slab to its original position and provides a more solid base on which to rest, there may be very serious problems that caused the sinking in the first place. For example, if you have soil erosion on your property (caused by poor drainage), concrete lifting will provide only a temporary band-aid – and may, in fact, prevent you from accessing the soil to address the problem.
One of the reasons why poly jacking may be a more common option in the future is because the concrete slurry used may not be fully waterproof. In some parts of the United States, such as the northeast and Pacific Northwest, the heavy rains can erode the concrete slurry over many years.
By contrast, polyurethane used in poly jacking is fully waterproof and doesn’t weigh as much. This prevents erosion as well as prevents the underlying soil from sinking further..
HOW MUCH DOES CONCRETE LIFTING COST?
For a deeper dive into the various costs involved in concrete lifting, see our guide ‘How much does concrete lifting cost?’ However, as mentioned above, one of the benefits of concrete lifting (when compared with other techniques) is that it is a relatively cost-effective process.
Generally, concrete lifting is a cheaper process than poly jacking, which involves drilling small holes into the cement and then pumping in polyurethane foam. Concrete lifting is also cheaper (usually by about 50%) than buying a brand new slab.
For a concrete lifting process, you can expect to pay somewhere between $500 and $1,200, with the average price being around $864.
Some of the factors that will affect this final cost are:
Any of these can push the overall price up above the $1,000 mark. However, the key point to make is that this still works out cheaper than most of the other techniques available.
if you need concrete lifting, then you often have very little say in the matter. Of course, you can delay the work and potentially experience further damage. However, what is certain is that if you do need to raise up a concrete slab, concrete lifting is usually the cheapest option available. It’s rare in-home repairs that you have an option that ends up costing a lot less than expected.