Concrete Raising FAQ
When does it make sense to raise my concrete rather than replace it?
Raising concrete can be a fantastic alternative to replacing concrete. If your concrete walkway, driveway, patio or floor is still structurally sound (no major cracks, spalling, scaling) and has just settled, then raising may be the most cost effective option. This is especially true if you only have a small section that needs to be repaired, since many concrete contractors will not do small jobs and then raising may be the only option. Also, raising concrete is a very quick and hassle free process compared to replacement – most projects are completed in around 1-2 hours.
What makes polyurethane injection (polyjacking) better than mudjacking?
The use of polyurethane to raise concrete and stabilize soil has many advantages compared traditional mudjacking which uses cement and sand. Below are just a few benefits:
- Longevity – Polyurethane will not shrink or breakdown over time
- Looks – smaller and fewer injections holes are needed.
- Performance –Extremely light compared to sand/cement and very effective at filling open voids
Do I need to be home for an estimate or when the work is being done?
No. Concrete raising is a pretty straightforward project. Just let us know the area you are looking to raise and our estimator we come by and leave you the quote.
This is also the case for when the work is being done, except if the area is inside such as a garage floor. Our crew will complete the work and the invoice will then be sent to you.
What causes concrete to sink?
Here are some of the most common reasons concrete slabs sink:
- Gravel base was never compacted properly during construction
- Concrete was built over soil that was once back-filled (such as around a foundation or pipe trench) and soil has now settled
- Water is draining or pooling around edge of slab which can cause the base to wash away over time
- Cracks and gaps in the concrete allow water to seep below the slab and cause seasonal frost heaving which can create voids
How can I prevent my concrete from sinking again after it has been raised?
The most important thing you can do is to fill all the cracks and gaps in your concrete where the settling occurred. A polyurethane crack sealer sold in caulk tubes is the best way to do this. Also equally important is to fill the area along the edges of your concrete with soil in order to prevent water from washing away the base.
Do you offer discounts if another neighbor also wants work done?
Yes! If we can save drive time you can save money. Look around your neighborhood to find others with the same concrete issues (shouldn’t be hard) and see if they want to team up to save some money.
I need a quote quickly. Do you always need to visit the site?
No. If the project is straightforward we just need some information and we can email the quote in a day or so to you without having to visit the property. Checkout our online estimate page to get started.
How long will it take to build my new concrete driveway?
Most concrete driveway replacement projects take three days to complete. Day one will be for demolition and installing the base and setting forms. Day two will be reserved for village inspection. Following the inspection we will return to place and finish your driveway. Additional days may be required for larger driveways. Read more about our process here.
What is the average cost to replace a concrete driveway?
While there are many factors that will determine the price of a new concrete driveway, the average price for replacing a two car garage driveway ranges from $5.50 to $7.50 a square foot. See our driveway cost page for more information.
What strength mix should I use on a driveway?
While many village codes call for at least a 3500 psi mix, we feel a 4000 psi mix should be used on a driveway to help it survive our harsh Chicago winters. Read more information about this here.
What can I do to get a better deal on replacing my driveway?
Team-up with your neighbors and save! We offer reduced pricing if multiple homeowners in a neighborhood have us complete work for them at the same time.
When can I walk on my new concrete?
You may walk on your new concrete the next day.
When can I drive on my new concrete?
You may drive across your new concrete after 7 days.
When can I park on my new concrete?
You may park your car on your new concrete after 10 days.
Why is my concrete different colors/shades?
Concrete takes months until it is cured. This will cause the concrete to look spotty because there are different amounts of moisture evaporating from each section of your concrete. Please do not be alarmed…this is very normal.
What should I do if I see a crack?
Due to the shrinkage that occurs in concrete, it is normal for cracks to form. We are very skilled at what type of concrete mix we use and where we design our control joints to minimize and control where cracks occur. Hairline cracks do not affect the structural integrity of your new concrete.
Can I use salt on my new concrete?
Salts or any other deicers claiming to be safe for concrete should not be used because they can damage your new concrete. The best way to keep your concrete safe in the winter is to keep it clean with a plastic shovel and to use kitty litter or sand for traction.
Will stamped and/or colored concrete fade?
Decorative concrete will fade if it is not properly maintained. We recommend your new decorative concrete be re-sealed every few years, however in high traffic areas it may need to be re-sealed more often.
How often do I need to seal my new concrete?
We recommend concrete to be pressure-washed and sealed with a commercial grade penetrating sealer every 5-10 years to maximize longevity and esthetics. Read about our Clean & Seal service.
What is concrete made from?
Concrete is a mixture of gray powder called “Portland Cement”, sand and gravel or crushed stone. The “Portland Cement” reacts chemically with water and hardens over time – a process called “hydration,” Concrete doesn’t “dry;” it “cures.” Additives are generally included in the mixture to improve its suitability for driveways. The most common are water-reducers that improve strength, and air-entraining mixtures that make the concrete resistant to cycles of freezing and thawing. Air-entrained concrete additives, containing billions of microscopic air bubbles, and reduce expansion and contraction. This helps concrete withstand Illinois’s large temperature range over our four seasons.
How Strong Is Concrete?
The compression strength (resistance to downward force) of concrete is determined by a number of factors. The most important is the ratio of water to cement in the mixture – the lower the ratio the stronger the concrete. Another way to increase the strength of concrete is to increase the amount of cement used. The strength of concrete is measured in pounds per square inch (PSI) Concrete used in driveways is generally 3,000 – 4,000 PSI, this strength is the result of using 5 bags of cement per cubic yard in the mix. If you increase the cement to 6.5 bags per cubic yard, the strength goes to 4000 PSI. At Catalano Concrete, we use 4,000 PSI for our concrete projects.
If Concrete Is So Strong, Why Does It Crack?
There are two kinds of concrete: the kind that is cracked and the kind that is going to crack. If a driveway contractor tells you his concrete driveways won’t crack, be skeptical, because it’s just not true. Although concrete has very high compression strength, it has very little tensile strength (resistance to being pulled apart). Because concrete shrinks as it cures, at a rate of about 1/16th of an inch for every 10 feet, there is strong tension pulling the cement slab. Because the whole slab can’t move over the ground, it can pull apart in the middle, causing a crack. Proper steel grid and micro-fiber reinforcement can help reduce this cracking tendency.
Control Joints Help Control Cracking
Control joints, as they are called, weaken the concrete slightly at the surface, so that when the concrete cracks it will likely follow the control joint and not be noticed. These control joints can be created in two ways. The concrete can be cut in straight lines, roughly ¼ of the depth of the slab. Hand-troweled control joints are another option, also often seen on sidewalks. The number and spacing of these control joints depends on the specific installation.
What Other Factors Cause Cracks?
In addition to shrinkage, there are four other main causes that contribute to cracking:
- Expansion and contraction due to temperature changes
- Concentrated heavy loads
- Poor un-compacted sub-base conditions
- Rapid water loss prior to finishing the concrete after it is poured.
All of these causes can be minimized with proper care and installation. A properly compacted sub-base of the proper thickness under the concrete is crucial. In Illinois’s cold winter climate, only air-entrained concrete should be used. Heavy vehicles, such as garbage trucks should be kept off the slab, especially near the edges.
How do I know I’m hiring a good concrete contractor?
To make sure your new concrete driveway gets off to a great start, you need to make sure the contractor who builds it has the experience needed to take all the factors above into consideration and the integrity to follow the best practices in building your driveway. Shortcuts and cutting corners during construction will only lead to problems. Choose your contractor wisely for the best results. Read about selecting a contractor here.
Schedule a Free Estimate
Whether you have uneven sidewalks, driveways, garage floors or patios, we provide hassle-free, no-obligation estimates for concrete raising projects, either in-person or online!