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How to fix concrete cracks

How to fix concrete cracks

Kelly Bacon is a licensed general contractor with over 40 years of experience in construction, home building and remodeling, and commercial building. He is a member of The Spruce Home Improvement Review Board.

How to fix concrete cracks

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Wide cracks in concrete are best patched and sealed with a concrete patching compound. Smaller cracks, less than 1/4 inch wide, can be repaired with a concrete caulk or liquid filler. Patching compounds typically are mixed with water and applied with a trowel. They have a texture similar to grout and can be smoothed and textured to blend with the surrounding area. However, the color of the patch will look like new concrete and will not match the old concrete. Hiding the patch completely requires painting the surface with an appropriate concrete paint.

Read and follow all directions from the manufacturer of your patching compound, as different products may have different steps or requirements for proper use.

How to Repair Wide Concrete Cracks

The secret to fixing wide concrete cracks is to undercut the sides of the crack to give it an inverted “V” shape. This helps the repair material to “key” into the crack, creating a mechanical bond in addition to the chemical bond between the patch material and the concrete.

  1. Chisel the crack with a hammer and masonry chisel to widen the base of the crack and to dislodge any loose material from the old concrete.
  2. Remove all debris from the crack, using a wire brush. If desired, clean the crack with a pressure washer or a garden hose and spray nozzle.
  3. Remove all water and debris from the crack with a wet/dry shop vacuum or a brush. Work carefully to remove all dust and grit from the crack. It's OK if the surfaces are wet, but there should be no pools of water.
  4. Mix the concrete patching compound, following the manufacturer's directions.
  5. Trowel the compound into the crack. Stab the trowel into the compound to remove air pockets and help work the patching material deep into the crack. Fill the crack up to the surrounding concrete surface.
  6. Smooth the surface of the patch with the trowel, feathering the compound into the surrounding concrete.
  7. Brush the surface of the patching compound with a dry paintbrush to texture the surface, if desired.
  8. Let the compound cure as directed.
  9. Paint or seal the surface of the patch and surrounding area, if desired.

How to Repair Narrow Concrete Cracks

Narrow concrete cracks can be filled using masonry crack elastomeric filler that can be applied with a caulking gun. Alternatively, many products come in bottles with an applicator tip. Very small cracks, such as hairline cracks, can be repaired using a vinyl concrete patching compound applied over the crack and then smoothed with a putty knife or trowel. For hairline cracks, applying repair caulk or crack filler over the cracks usually is not effective, as the caulk tends to peel off of the surface over time.

Narrow cracks can be deep, often extending through the entire thickness of the concrete slab. Therefore, it's a good idea to start the repair by stuffing foam backer rod into the crack to create a base to hold the repair material. Backer rod is sold in a variety of sizes; use a rod diameter that is slightly larger than the width of the crack. Stuff the backer rod into the crack with a screwdriver to a depth of 1/4 inch. Fill the crack with the repair material, following the manufacturer's directions.

If your driveway, patio or other concrete surface has cracks, they can often be repaired. In some cases concrete crack repair can be a simple DIY project, in others it may require a professional concrete contractor to correct the damage and in the most extreme cases your concrete may need to be removed and replaced.

REPAIRING SMALL CRACKS

For minor cracking, here’s how to fill cracks in concrete with a concrete patch or crack filler:

How to fix concrete cracks

1. Chisel out the crack to create a backward-angled cut, using a cold chisel and a hammer.

How to fix concrete cracks

2. Clean loose material from the crack using a wire brush, or a portable drill with a wire wheel attachment.

How to fix concrete cracks

3. Apply at thin layer of bonding adhesive to the entire repair area using a paint brush. The bonding adhesive helps keep the repair material from loosening or popping out of the crack.

How to fix concrete cracks

4. Mix vinyl reinforced patching compound, and trowel it into the crack. “Feather” the repair with a trowel, so it is even with the surrounding surface.

How to fix concrete cracks

Wide crack variation

If the width of the crack is an inch wide or larger, the process of repairing cracks is slightly different. Chisel out the crack and clean loose material as listed above. Then pour sand into the crack within the surface. Prepare sand- mix concrete, adding a concrete fortifier, then trowel the mixture into the crack. Feather until even with the surrounding surface.

Tip: If you don’t like the way your repairs look, consider concrete resurfacing for a fresh, uniform surface.

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Fast Patch – Concrete Repair Simply mix with water and trowel

HOW TO TIPS FOR FIXING CRACKS

IS IT WORTH FIXING, OR SHOULD IT BE REPLACED?

Concrete that is cracked only on the surface, or has hairline cracks where both sides of the crack are still level can be successfully fixed. See basics of concrete repair and troubleshooting

Cracked concrete should be replaced if due to the three conditions listed below. Any patching material used to fill these types of cracks will only be a short term fix. You definitely would not want to patch these cracks and then spend money resurfacing the concrete or doing a decorative topping.

How to fix concrete cracks

Widespread, deep cracks, settlement has occurred

When concrete is cracked all the way through the slab it should be replaced. Sometimes this is due to the weight of large trucks, improper preparation of sub grade, erosion of sub grade, or other reasons.

  • Remove the concrete
  • Remove the sub grade
  • Replace sub grade with compactable material (sometimes existing material is ok)
  • Compact the sub grade
  • Pour back concrete

How to fix concrete cracks

Sunken concrete

Sunken concrete occurs when the sub grade was not prepared properly. Loose dirt may have been used for the sub grade. When this dirt settles-sometimes due to sprinkler or rain water going under the concrete- the concrete is unsupported and will be more susceptible to sinking.

It is possible that the sub grade was compacted and the concrete was subjected to extreme weight which caused the concrete to sink. This can often we fixed with special equipment that raises the concrete without damaging the slab (HMI Concrete Lifting & Raising Equipment).

  • Remove the concrete
  • Remove the sub grade
  • Replace sub grade with compactable material (sometimes existing material is ok)
  • Compact the sub grade
  • Pour back concrete

How to fix concrete cracks

Frost Heave

Frost heave is very common in cold climates. Moisture in the ground freezes and the concrete pushes upward.

  • Remove the concrete
  • Remove the sub grade
  • Replace sub grade with compactable material (sometimes existing material is ok)
  • Compact the sub grade
  • Pour back concrete

Get the advice of a local soils engineer on sub grade preparation for your area and material needed to prepare sub grade (sometimes existing material is ok)

Whether you do the job yourself or contract it done-these are the steps to follow. See what is concrete and ordering concrete for information on ordering the right type of concrete

That’s when it’s time to take action — but first, you should know your options.

How to fix concrete cracks

It’s tempting to replace an unsightly driveway like this one, but it’s often unnecessary.

Replacing vs. Resurfacing

You could break up the concrete slab and pour a new one when cracks form, but that would take a lot of time, leave a big mess, and cost a lot of money.

After all, you’d have to remove the existing driveaway, clean up the pieces and haul them away, and then you’d have to prep the ground and pour a new slab — complete with steel reinforcement and control joints.

A concrete driveway’s typical installation costs range between $1,500 and $6,000, with the average cost being $3,000, or $6 per square foot, according to HomeAdvisor.

It makes sense to pay that much for a new driveway, but not if you have an existing driveway in good shape except for a few cracks.

Fortunately, there’s another option: repairing your old worn, spalled concrete driveway with Quikrete Re-Cap Concrete Resurfacer. You get to keep your existing driveway, and simply cover the part that’s causing problems!

Resurfacing concrete requires less time, less mess and — you guessed it! — less cost than the alternative. The typical driveway resurfacing ranges from $300 to $500, according to HomeAdvisor.

The process is straightforward and any do-it-yourselfer can tackle this project in a day.

How to fix concrete cracks

A resurfaced concrete driveway looks as good as new — at a fraction of the cost.

How to Resurface a Concrete Driveway

If you’re ready to resurface your concrete driveway, just follow these steps:

Remove debris. If a crack is less than a quarter-inch, it’s a prime candidate for simple resurfacing. So grab a screwdriver and scratch away at any debris you see. Then use a wire brush to clean the area. And then use a whisk broom or a leaf blower to clear the area.

Wash the driveway. Wet down the driveway with a pressure washer. Then add Quikrete Etcher, Cleaner and Degreaser to the machine’s reservoir and spray it on the surface. After that, attach a high-pressure nozzle to the washer and thoroughly clean the surface.

Mix concrete and water. Mix Quikrete Re-Cap Concrete Resurfacer with water in a 5-gallon bucket. Chuck a mixing paddle in a ½-inch drill to quickly prepare the patching material, which should have a thick consistency.

Fill the cracks. Pour the mixture on the cracks and use a flat-edged trowel to force it deep inside them. Then smooth out the surface.

Let dry. Allow the material to dry overnight, and then mix a much thinner batch of resurfacer. Before applying it, wet the concrete down to prevent it from drying out too quickly.

Resurface. Spread the resurfacer on the slab using a rubber squeegee. Try to apply an even coat without a lap mark.

How to fix concrete cracks

Give the resurfaced concrete driveway a “broom finish” to prevent slips.

Prevent slips. When the resurfacer starts to set, use a broom with an extended handle to give the fresh concrete surface some texture and prevent it from becoming slippery when wet. This is often called a “broom finish.”

Resurfaced concrete can handle foot traffic after it has set for about six hours, and cars can drive on it once it has cured for 24 hours.

Best of all, your concrete driveway will look new again with minimal work — and expense — compared to pouring a new slab.

Despite being one of the toughest and most durable surface materials anywhere on Earth, concrete can still crack. Unsightly and problematic, these cracks can ruin the look of a concrete driveway or weaken the structural stability of foundations. Luckily, concrete cracks, whether big or small, can be repaired.

In this article, discover the most common causes of concrete cracks and the most effective ways to fix them.

Here at Total Concrete, we can delivery concrete across Berkshire, Hampshire, Woking, Surrey and beyond – to get a free quote, use our online quote form or call us on 0800 859 5371 .

Why does concrete crack?

There is only one reason why concrete cracks: its tensile strength is exceeded by the net tensile stresses induced within its matrix. Put simply, concrete cracks when it experiences more tension than it can withstand.

There are many circumstances where this may occur, the most common being:

  • Excessive weight, such as from large vehicles, bearing down on the concrete.
  • Heat, causing the concrete to expand and push against another inflexible material.
  • Water, which has found its way into the concrete, freezes in cold temperatures and expands.
  • Premature drying, which reduces the moisture in the concrete too quickly. This is perhaps the most common cause of cracking and happens when the concrete is still in its plastic state (before hardening).

How to fix small concrete cracks

Small cracks may not risk any serious structural damage, but they can still ruin the aesthetics of your concrete. Luckily, small concrete cracks are simple to fill using masonry filler or similar products.

Hairline cracks can be remedied using a vinyl concrete patching compound. Just a few steps will get your concrete looking good as new:

1. Use a cold chisel and a hammer to create a backward-angled cut.

2. Use a wire brush to clean loose material from the crack.

3. Use a paint brush to apply a thin layer of bonding adhesive to the area.

4. Mix vinyl reinforced patching compound and use a trowel to apply it to the crack. Make sure it is even with the surrounding surface.

5. Let the compound cure.

How to fix large concrete cracks

Larger cracks may require a little more handiwork, but they can also be repaired fairly quickly and easily.

1. Undercut the sides of the crack to create an inverted ‘V’ shape.

2. Use a chisel and hammer to widen the base of the crack and dislodge any loose material.

3. Use a wire brush to remove all debris from the crack.

4. Use a wet/dry vacuum or a brush to remove water and remaining debris from the crack.

5. Mix the concrete patching compound and use a trowel to apply it to the crack. Make sure it is even with the surrounding surface.

6. If needed, brush the surface of the patching compound with a paintbrush to texture the surface.

7. Let the compound cure.

Common concrete cracks

We provide concrete for all types of domestic and commercial projects, so we know that concrete can be used for foundations to driveways. But what are the most common concrete cracks?

Cracks in concrete driveways

Concrete driveways are a popular choice for a home or business driveway, but excessive usage with heavy vehicles or machinery, or adverse weather conditions can cause cracks in the surface. One of the main causes of cracks in a concrete driveway is water build up. If the surface collects water and does not drain away, this can cause damage, and ultimately lead to cracks.

How to fix concrete cracks

Cracks in concrete foundations

More common in older properties, cracks in concrete foundations can be found above the surface, or below the surface of a building. Many people think that cracks can form in foundations due to a buildings age, but this is not always the case.

Pressure on the foundations can be a factor – but the most common reason why concrete foundations crack, is soil. Dry or expanding soil can cause the concrete to move, causing cracks. If concrete has room to move, it will most likely end up cracking.

How to fix concrete cracks

Cracks in concrete walls

Cracks in concrete walls can be due to a number of potential issues. Main causes could be down to:

Movement in other structural aspects of the building (like wooden frames due to weather), problems with the foundations, strain on the concrete (from construction work), or damp.

How to fix concrete cracks

Cracks in concrete roads

When looking at concrete roads, these are usually built by government contractors – so there are several surveys and studies into damage, and wear and tear for concrete roads. Again, it’s not always due to age or usage, but when we look at concrete roads, it is usually linked to how they are built. Again, foundations and pressure on the concrete can cause cracks.

However, the most common causes of cracks in concrete roads are; inadequate base support under the concrete slabs, and issues with thermal expansion of the aggregates used under the concrete. If the aggregates get warmer, or warmer than they should be, they will expand, putting pressure on the concrete and changing the surface area that the concrete is laid on.

If the base support is not adequate for the pressure of the concrete slabs, the base itself can crack under pressure, causing the road above to do the same. Due to both of these issues, the base concrete slabs that make up the road surface, have room to move – so it causes cracks.

How to fix concrete cracks

At Total Concrete, we supply all the concrete you need for your project. Big or small, commercial or domestic, we have the concrete you need — all available for next-day delivery. We offer a range of products and services, including ready mixed concrete, concrete screed and more.

We even offer on-site mixed concrete, ensuring you get the freshest and most precise mix possible. Never overpay for concrete — get the exact amount you need, when you need it.

We serve customers across Berkshire, Hampshire, Woking and Surrey. Contact our team today to arrange your concrete delivery.

We discuss how to fill and seal cracked concrete walls for a simple, permanent repair.

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Outside of hairline cracks, larger stress cracks occur when a house settles or the ground beneath it shifts. These types of cracks don’t usually pose a threat to the structural integrity of a house, but they do allow for a potential opening for groundwater, insects and radon gas.

We’ll show you a simple and effective way to patch cracks with the best concrete crack filler.

Fix Concrete Cracks in 8 Steps

Step 1: Repair a Foundation Crack With an Epoxy Sealer

Photo Geoffrey Gross

We repaired a foundation wall, which had an 8-ft.-long crack that leaked water into the basement during periods of heavy rainfall. To permanently patch the crack we used an epoxy-injection system from Polygem, called the Liquid Concrete Repair Kit (about $60).

Each kit contains a two-part epoxy crack sealer, two 10-oz. tubes of Liquid Concrete Repair (LCR), a viscous epoxy that comes in a caulk-type cartridge, and seven plastic injection ports that deliver the LCR deep into the crack. There’s enough material in each kit to repair a 1/16-in.-wide x 8-in.-deep x 8-ft.-long crack.

Before you start, check to make sure the crack is dry. If the crack is slightly damp, dry it with a blow-dryer, then wait 15 minutes. If it remains dry, proceed with the repair. However, if the dampness returns, water is still seeping into the crack and you’ll have to wait for it to dry out on its own.

First, scrub the crack clean of any loose concrete, paint or old crack filler using a wire brush. Remove all dust and debris with a shop vacuum.

Step 2: Block Out the Injection Ports

Photo Geoffrey Gross

Tap 3-in. (10d) finishing nails partway into the crack, spaced 12 in. apart. You’ll use them to align the injection ports with the crack.

Step 3: Mix the Epoxy Sealer

Photo Geoffrey Gross

Open up the two containers of epoxy crack sealer and scoop out equal amounts of Part A and Part B; use two separate sticks to avoid contamination. Mix the two parts on a scrap board using a clean putty knife; blend until you achieve a uniform gray color.

Step 4: Attach the Injection Port

Photo Geoffrey Gross

Spread some sealer onto the base of one of the plastic injection ports, being careful not to plug up its hole. Slide the port over one of the nails sticking out of the crack and press it to the wall. Install the remaining ports in a similar manner.

Step 5: Spread Sealer Along the Crack

Photo Geoffrey Gross

Next, mix up a slightly larger batch of epoxy sealer and apply it to the entire crack using a 1 ½-in.-wide putty knife or margin trowel. Spread the sealer about 1/8 in. thick and 1 in. on either side of the crack. Also, cover the entire flange of each injection port with crack sealer, leaving only the extended neck portion showing. Smooth out the sealer and feather its edges with a paintbrush dipped in mineral spirits.

Step 6: Inject the Epoxy into the Crack

Photo Geoffrey Gross

If the other side of the wall is accessible, see if the crack goes clean through. If it does, seal it up with crack sealer, too. Allow the sealer to cure for 6 to 10 hours before injecting the epoxy. Thoroughly mix the LCR epoxy using the plunger rod that comes with the kit. Place the LCR cartridge into a caulk gun. Starting at the lowest injection port, dispense the epoxy into the crack. Continue squeezing the trigger until epoxy begins to ooze out of the port directly above.

Step 7: Seal Up the Injection Ports

Photo Geoffrey Gross

Remove the gun and plug up the port you just filled. Now insert the cartridge tip into the port that’s oozing and squeeze the trigger to dispense the epoxy. Repeat this procedure for the remaining ports; plug up each one before moving on to the next.

Step 8: Cut Away the Injection Ports

Photo Geoffrey Gross

Allow the LCR to cure for five days, then cut off the necks of the ports with a hacksaw. If desired, you can patch the severed ports with a little crack sealer.

Resource:

Polygem
Box 609
Dept. TH700
W. Chicago, IL 60186
Polygem
630/231-5600

Concrete floors are made to undergo constant abuse from heavy traffic, so it is imperative that the floor is poured and installed properly or it will run a higher risk of cracking. As we all know, nothing lasts forever and even the best concrete is not made to withstand years of wear and tear, especially in commercial and industrial applications.

Commercial flatwork, concrete especially, takes more abuse from vehicles, individuals, and the elements, than your standard residential applications. For this reason, contractors turn to specialty coatings, aggregates, and reinforcing schemes to meet the heavy demands and requirements of buildings.

There are a number of reasons concrete cracks, and for the most part, the fracture is merely an eyesore. The damage may not immediately mean a structural defect, unless the separation occurs vertically or horizontally, revealing a potentially unstable sub-grade. Either way, eyesore or safety hazard, it’s always a good idea to have an expert out to take a look and let you know what you’re dealing with and what the options are.

Reputable concrete repair company, K&E Flatwork, knows the causes behind cracks and works expertly to prevent these potential problems during installation.

Find out how to repair cracks in concrete to ensure a durable, seamless surface for the years to come.

Probable Causes of Cracks in Concrete

1. Lack of or Incorrect Spacing of Control Joints

Control joints, also known as planned cracks, are intentionally placed to allow movements caused by changes in temperature and drying shrinkage. A good contractor should know where to place joints and where cracks are likely to occur.

2. Improper Concrete Strength

A bad concrete pour may lead to the failure or deterioration of concrete. Concrete comes in a variety of strengths to meet the demands of various applications. The contractor should know how to choose which product has the right strength, workability, shrinkage, and permeability for each project.

3. Poor Soil Conditions

It’s acceptable to pour flatwork on native grade, where soil conditions are ideal. But in cases where a sub-grade or sub-base is required, the soil should be compacted and backfilled for the concrete to settle properly. Contractors should never pour concrete on frozen ground, as well. When contractors ignore these requirements, there is a possibility that the slab will crack.

Other construction oversights that may induce cracking are movement of formwork, incorrect placement of reinforcing steel, improper curing and compaction, and errors during curing and final finishing operations. Failure to take the necessary precautions will ultimately result in cracks and serious damage.

4. Excess Water

Water is an important ingredient in mixing and pouring concrete. But not understanding how water reacts with cement will lead to structural problems. Due to the porous characteristic of concrete, the material expands and contracts when temperatures fluctuate. Too much water also reduces its durability and strength. When added during finishing, it could result in crazing, scaling, or dusting.

A reputable contractor should know how to make a proper mix. When the proper ratio is not followed, the final slab is likely to crack over time. In some areas, ambient relative humidity may also have an influence on the movements of concrete.

DIY Solutions for Damaged Concrete

You will find plenty of concrete products in the market today, giving you quick and inexpensive options to remedy cracks, voids, and flaking.

Here are some examples:

Epoxies for Crack Injections

An epoxy crack injection is a quick fix for localized damage. They come in various viscosities to accommodate cracks of different widths. Prized for their exceptional compressive strength, epoxies are a popular choice for fixing cracks that call for structural repair. But it may not be the best solution if the crack is leaking or if the crevice is too deep.

Sealing Cracks with Polyurethane

Polyurethane foams are useful when materials are leaking out of the crevice. Polyurethane injects are fast-setting, elastomeric, and waterproof foams that quickly harden and stay intact within the void. While these foams take minutes to settle and harden, and easier to work with than epoxies, they add zero compressive strength to the material. This is why contractors use polyurethane mostly for residential applications.

Urethane Caulk to Keep Water Out

It’s important to seal the gap right away to keep water out and protect the foundation of the flatwork. Filling gaps with durable urethane caulk is a popular option. It is practically easy to acquire and apply. These fillers are also long-lasting and they help prevent the flatwork from further cracking and eroding.

Note that these concrete crack fillers and sealants are chemical-based. Wear gloves, glasses, and protective clothing when working with these products to avoid inhalation, and skin and eye contact. Take the time to study the drying time of the material, how and where to apply it, and what type of materials you need to achieve the desired outcome.

Replace or Repair?

Quick, DIY fixes are less expensive compared to new flatwork. And with so many options available, there are ways to restore the strength and aesthetic appearance of concrete surfaces. But keep in mind that the solutions listed above are merely Band-Aid fixes for minor issues and may not work for everyone.

In some instances, deep cracks are merely a symptom of a more serious structural issue. A DIY solution is not going to resolve that complex problem. You need to know the extent of the damage and consult with a professional to avoid further costs and ensure safety.

Worn out surfaces or even minor issues can create real safety risks and liability. If taken lightly, it might jeopardize the entire integrity of the structure. If the amount of cracking or curling is unmanageable, you may want to consider professional concrete crack repair.

For expert replacement, contact K&E Flatwork, the largest concrete repair company in Kansas City.

How to fix concrete cracks

Unsightly cracks in concrete not only detract from the look of a garage or patio, they can also lead to further problems as moisture seeps into the concrete.

Luckily, there’s an easy way you can repair a cracked concrete slab or wall and prevent further damage down the track.

Sikadur Concrete Fix is a two part epoxy adhesive and filler that can be used as a bonding bridge adhesive paste for concrete and most building materials.

It’s simple and easy to apply and can be used for repairing cracks, holes and voids in concrete floors and walls.

It also works as a structural adhesive for a range of materials including stone, ceramics, fibre cement, masonry, metal and timber.

To repair cracks in a concrete floor, first ensure that the area is free from dust, grease and surface contaminants.

Concrete fix can be applied to both dry and damp surfaces, but standing water in any voids, pits or pores should be removed prior to application.

While wearing safety glasses and chemical resistant gloves, pre-mix both parts separately, then mix equal parts of each together in a suitable container. Mix thoroughly for three minutes with an electric drill and paddle mixer.

Use a trowel to apply concrete fix to the prepared substrate and smooth it into the crack or to form the desired shape.

How to fix concrete cracks

Apply Sika Concrete Fix to corners using a shaped trowel

The paste cures rock-hard, so make sure you clean all tools and surfaces using Sika Colma Cleaner before it hardens.

Repairing cracks in concrete will improve the look of your concrete slab or wall and minimise the risk of further damage.

No one wants to be surprised by a new crack in their concrete floors, especially if they were just installed. Learn why concrete floors crack, how installers can prevent premature cracking, and what to do when you discover a crack.

What Causes Concrete to Crack?

Even if you hire the top concrete installer to pour your concrete floor, you may still end up with cracks down the line. Concrete is a fickle material that can crack at any point in its lifetime, from right after it’s poured to years later. As a result, it’s almost impossible to avoid cracking. Below are the common issues that can cause concrete floors to crack.

Mixture Mistakes

Concrete floors are a mixture of cement, aggregate, and water. Before pouring a slab, the installation crew needs to perfect its concrete mix to prevent cracks. If your mixture is extra soupy, the concrete slab will shrink significantly as the excess water evaporates, and the force of the shrinkage can cause cracks as the slab dries. However, mixtures that are too dry will harden into weak, crumbly concrete.

Pressure and Temperature Changes

It can take up to a month for a large concrete slab to completely dry and cure. The process should be gradual and uninterrupted. Patience is key when waiting for concrete to cure—putting weight on it too soon will crack it. You should also closely monitor your concrete as it dries and prepare for extreme weather because heat can accelerate the drying process and cause shrinkage. In contrast, cold conditions can weaken the concrete’s structure.

Improper Installation

Because concrete is prone to cracking, expert installers can cut control joints into a slab after it’s poured. Control joints are intentional cracks that help prevent uncontrolled cracks from happening during the installation process. Sidewalks utilize control joints to force cracks to form in an aesthetically pleasing straight line. Without control joints, shrinkage cracking will occur randomly and threaten the slab’s structural integrity.

Lack of Foresight

Concrete flooring projects require a lot of planning. If you fail to consider how your business will use its floors, you could end up with beautiful flooring that doesn’t meet FDA regulations and can’t withstand the weight of your machinery. Before beginning a concrete floor project, you need to consider how you will use your floors, if they will be exposed to extreme temperatures or chemicals, and if your business is subject to government regulations.

The Different Types of Cracks in Concrete

There are many different types of concrete cracks that you may encounter during the lifespan of your polished concrete floors. Some are completely harmless, while others require repair. Common types of concrete cracks include:

  • Plastic shrinkage cracks: During the plastic state of the concrete drying process, the slab is still pliable. As water evaporates out of the concrete slab, it leaves behind gaps that can turn into plastic shrinkage cracks. Installers can prevent these cracks by using control joints or repair them by sealing the concrete’s surface.
  • Structural cracks: After concrete cures and is ready for use, it can still crack if too much weight is placed in one spot. Additionally, soil movement and water leaks can disturb the foundation below the slab, causing it to move and break. You should repair structural cracks to avoid further damage.
  • Hairline cracks: Thin cracks that form in your concrete floors during the curing process are considered hairline cracks. These typically don’t threaten the structure of your concrete, but they can absorb moisture. You can repair hairline cracks by sealing or resurfacing your concrete floors.

Prevent and Manage Cracks in Concrete Floors

If you operate a warehouse, food and beverage manufacturer, car dealership, factory, or other industrial space, polished concrete floors are an affordable, heavy-duty flooring option. If you want your concrete floors to last, it’s crucial to prevent and repair cracks.

The best way to prevent cracks from occurring is to consult an experienced concrete installation company to discuss your floors’ use and structural needs. Our team at Ardor Solutions will assess your needs and identify any legal, structural, or environmental factors that you should consider.

We have over 15 years of experience installing concrete floors, so you can be sure that our installation team will take the time to correctly install your floors and prevent cracks. And if you need a team to repair your damaged concrete floors, Ardor Solutions can help you decide on the solution that will best fit your budget. Contact us today to learn how we can install, repair, or replace your concrete floors.

Although concrete is strong, durable, and long lasting, there are times when cracks occur. In most instances, fixing cracked concrete is a viable solution compared to ripping the concrete out and starting over again. In addition to concrete resurfacing, SUNDEK contractors are experts in concrete repair.

How to fix concrete cracks

Why does concrete crack?

Concrete can crack for a variety of reasons. If it isn’t installed properly, it will eventually crack. Improper installation includes everything from having the wrong amount of water in the mix, poor conditions that caused the concrete to dry too quickly, missing control joints and more.

However, even properly installed concrete can crack. Concrete has great hardness (compressive strength), but it does not have good elasticity (tensile strength) which is the ability to stretch and bend very far.

Diagnosing the cause of the cracks in your concrete

It’s important to figure out why your concrete is cracking so that you can prevent it from happening again. Understanding the cause will also inform the method used for repair.

For example, damage due to traffic or wear and tear will have different repair requirements than damage due to exposure to moisture or freeze/thaw cycles in the winter. If the damage is due to corrosion in the reinforcing steel rebar structure of the concrete, it’s going to need more than just resurfacing and may need to be replaced entirely. A qualified concrete contractor will be able to accurately diagnose the source of the problem and give you options for repairing or replacing it.

Contact a local SUNDEK contractor to get a free quote for repair on your cracked concrete

How to fix concrete cracks

What are the options for fixing cracked concrete?

Have SUNDEK do a Custom Scoreline Effect. This technique, invented and perfected by SUNDEK contractors more than 40 years ago, involves working small cracks into the design of the concrete surface. Since the cracks are doing their job in controlling the natural expansion and contraction of the concrete as it heats and cools, we let them do their thing, but we incorporate them into the design. (We sometimes call this technique “Mother Nature’s Expansion Joints”).

With the Custom Scoreline Effect, you get a two-year warranty—if another crack appears during that time, SUNDEK will create a new scoreline with the new crack.

Repair then resurface. With this option, we can repair cracks in your surface then apply a coating to the top of the entire surface, giving you a brand new look.

Repair just the crack. If the damage from the crack is not very deep or widespread, it’s sometimes possible to just patch up the crack. If this is the case, a contractor can grind open the hairline cracks then brush on a layer of bonding adhesive. Then they will apply the repair material, smooth it out, and let it dry.

Remove and replace the cracked concrete areas. This option can get pricey, but depending on the width of the crack, it can be necessary. A SUNDEK contractor can advise you if you need to tear out and replace your surface.

Saw cut the concrete at the cracks and epoxy weld the structural cracks. This is also known as the cut-and-paste option. It’s pricey and not foolproof. It can be difficult to find someone who does this type of work and usually it has a very limited warranty.

Can I fix cracked concrete myself?

Crack repair is a delicate process. Aside from needing all the proper materials, you need to know how to mix the product properly to prevent repeat damage. You also need the right drying conditions. If the crack isn’t repaired correctly, the repair work is not going to last.

A professional, experienced contractor can repair the cracks in your concrete, and they can assess the damage and recommend the best solution for the job to ensure the crack doesn’t reappear.

SUNDEK contractors have more than 50 years of experience, so we know how to address the nuances that occur and know the common pitfalls to avoid.