Concrete is an incredibly durable, strong, and versatile substance. This is why it can be found in buildings and structures of all sizes, all around the world. Resistant to fire and extreme temperatures, it makes the perfect material for building homes that will stand the test of time. That’s not to say that it is without flaws, however. Concrete has some weaknesses that make it prone to issues like cracking, pitting, flaking, and staining when it is placed into unfavorable conditions (or when it has some fundamental defects).
Learning to read the signs of damage and deterioration in your property’s concrete surfaces is an incredibly useful skill that could save you huge amounts of money on repairs in the long run. Catching issues early, especially structural issues, is incredibly important in preventing the formation of avoidable secondary and tertiary damage.
Concrete 101: How It Is Made and How It Can Go Wrong
The first buildings that were made of what we would recognize as concrete today, were built by Bedouins in the areas of what are now northern Jordan and southern Syria in around 6500 BC. Of course, the cement used then would have been wildly different from the Portland cement that we use today, but it would still be recognizable to most people.
If you want to understand why concrete surfaces can be so prone to cosmetic issues like staining, pitting, and flaking, you need to know how it is made and how the manufacturing process can go wrong. After all, concrete is a brittle material that has a very low tensile strength in proportion to its compressive strength. In fact, the tensile strength of most concrete is around 10% of its compressive strength, which means it cracks very easily.
How Concrete Is Made
In its simplest form, concrete is a mix of rock aggregate, paste, sand, and water that forms a liquid mix that sets into a hard, fire-resistant, weather-resistant, rock-like material that can be used for building. Of course, getting the perfect concrete requires that you know how to mix it properly.
The key to creating strong, durable, and resilient concrete lies in the proper proportioning of the various ingredients in the mix. Too much or too little water, for example, will make the concrete vulnerable to damage. If there is not enough paste to fill the holes between aggregates, the concrete will have large gaps in it. If the mix is too watery or not mixed well enough, it may have large fault lines or even fail to set properly. Good concrete will generally be made up of 10 percent cement, 30 percent sand, 40 percent rock aggregate, and 20 percent water. This gives a good balance and a strong result.
Concrete is mixed and made through a process called hydration in which the water in the concrete mix reacts with the cement and bonds the other materials together firmly. The process of curing also requires water; concrete must be kept moist as it cures to ensure optimal strength once it is fully set.
What Can Go Wrong
There are two main problems that can occur in the creation of concrete; the mixture itself can be imbalanced or unsuitable, or the process of curing can be undertaken poorly. When this happens, it can affect concrete in a number of ways.
The lesser possible outcome is that the concrete that is created is weaker than it should be. This can leave it prone to cosmetic damage (like pitting and staining) and make it more vulnerable to cracking under pressure. The most serious consequence of poorly mixed or cured concrete is the total failure of the batch. If this happens, any structure made with the concrete may start to deteriorate at an accelerated rate and could lead to localized or widespread collapses in the structure.
What Causes Concrete to Pit, Stain, or Flake?
There are many things that can damage concrete, but very few that will cause cosmetic issues like pitting, flaking, staining, or spalling in isolation. The following issues are the most likely to be at fault if you find these issues in your concrete surfaces.
Adverse Weather/Environmental Conditions
The climate and weather in Indiana can be a little unforgiving at times. The warm, humid summers and cold, wet winters can make it hard for any property to avoid damage, and for porous materials like concrete, it can be incredibly stressful. The most damaging process, however, is repeated cycles of freezing and thawing.
As the water in concrete freezes and thaws, it will expand and contract repeatedly. This leads to damage and small cracks inside the concrete. This activity is most common just below the surface of concrete and, as such, can lead to cosmetic, surface-level damage like flaking, pitting, and spalling.
Likewise repeated heavy rainfall or a leak somewhere inside your home will lead to concrete staining over time. Finally, if seepage impacts your home, it will leave a telltale white residue that can stain concrete surfaces over time.
Some of the chemicals we use around our homes can be incredibly damaging to concrete surfaces and lead to cosmetic damage and deterioration. This is also most likely to occur in winter because the chemicals that are most damaging to concrete tend to be found in the salts and sprays that are used to defrost and de-ice.
These reactions are cumulative and can take many years to show. However, cosmetic issues on your driveway are likely to be due to chemical reactions as well as environmental exposure and other issues.
Failing to mix or cure concrete correctly will result in it being far more susceptible to damage and deterioration. If you have concrete that was poorly mixed or that was not allowed to set properly things like environmental factors and chemical corrosion will be far more serious in their effects.
Likewise, if the concrete has become damaged as a result of other issues like the movement of expansive soils, cosmetic damage will seem more pronounced and may even be more serious.
Structural damage is far more severe than staining, pitting, and flaking, but if a concrete surface is starting to crack and bow as a result of ongoing pressure, it will be more susceptible to also developing cosmetic issues like flaking or spalling.
The things most likely to cause structural damage to concrete surfaces are problem soils, hydrostatic pressure, and movement in the structure of a home.
If you see concrete pitting, staining, and flaking in or around your home, it is most likely being caused by one of these issues. Of course, there is a chance that there are other factors at work, or that this is a compound issue. As such, make sure you look for the following problem signs.
Concrete Pitting, Flaking, and Staining
If you have noticed unevenness or sinking in sections of your concrete flooring, it’s best to act quickly. The likely causes of these issues are many and none of them are benign. From environmental factors to fundamental defects in the structure of your property, they are all serious and require expert intervention.
The most common cause of sinking and cracking in an interior concrete floor is damage to a property’s foundation. This kind of damage can also cause pitting and spalling because of the immense pressure that it puts concrete under—a network of stress fractures can weaken concrete to the point that it starts to deteriorate at an incredibly fast rate.
The most common foundational issues that you might encounter in Indianapolis, Indiana, homes include settlement and subsidence. Both of these issues have their root in problem soils beneath the property and both can cause widespread damage to the rest of your property. Settlement is most likely to occur in periods of drought when the soil under a property can shrink or become dry and loose. Subsidence, by contrast, is far more likely to result from periods of heavy rainfall when the soil becomes soft and marshy. Either way, specialist concrete lifting services are the best response.
Defects and Damage
If you have exterior concrete surfaces that are starting to flake, spall, and even sink, then the most likely causes are damage as a result of exposure to harsh environmental conditions and chemicals or defects in the concrete itself. Concrete defects are not overly common, but when one property in a certain area has issues with them it is likely that others will too.
An outlier issue is something like soil washout or erosion that removes the soil from around and under a structure gradually, leaving it without support. This will often cause concrete surfaces to dip and sink under their own weight, thereby cracking and crumbling in many places. The weight of cars on a driveway will only make this worse. This is why it is best to act quickly; if you leave concrete damage to get too bad there is a chance that replacement will be your only option and this is far more expensive than repair.
Concrete lifting processes are more sophisticated and effective than they have ever been. They can help you restore sunken and damaged concrete surfaces to their intended position so that they can be resurfaced and cosmetically repaired.
First and foremost, professional concrete lifting services will put your concrete surface back into place and secure it there. This means that you get a long-term solution that will prevent the recurrence of the issue, assuming you installed the right solution for your situation. For example, mudjacking is a good solution for exterior concrete surfaces that are not sinking because of weak or loose soil.
Because mudjacking uses concrete slurry to lift and set the damaged surface in place, it is a very heavy solution. If the soil under the concrete is weak and it is this that has caused the issue, it will absolutely recur. However, if the soil is strong, mudjacking will provide the perfect solution. In cases where the soil is very weak, a solution like polyurethane foam may be far preferable. If the sunken concrete slabs are inside a home, however, it may be necessary to use foundation piers as well as polyurethane foam. The complexity of these issues is just one reason why it is a good idea to call a professional.
As well as producing a strong, stable, permanent solution to sinking or damaged concrete in and around your home, concrete lifting processes can repair its appearance and make your property look good again.
One of the most effective ways to restore the appearance of damaged concrete is to resurface it. This process is fairly quick and can be undertaken by any concrete repair specialist very quickly. By applying a thin layer of fresh concrete to the affected area, concrete resurfacing creates a smooth and flawless surface once more. This makes damaged concrete look good as new and fills in any cracks that are still there.
While we understand that DIY is an attractive prospect, we urge you not to try to lift and repair damaged concrete alone. There are simply too many things that could go wrong, causing injury to you and damage to the property itself.
DIY Often Goes Wrong
The main issue with trying to lift sunken concrete alone is that this is a form of structural repair. This means that if you make a mistake, even a small one, the consequences will be huge. Success is dependent not only on your ability to properly assess the damage and diagnose the underlying problems but on having the right tools and products to do the job.
The products and tools used to lift, repair, and secure damaged concrete that has started to sink or crack are specialized. In the wrong hands, they can be very dangerous. As well as the chance of injuring yourself, you run the risk of damaging your home. If you do enough damage, you could end up having to replace the concrete entirely.
Professionals Can Cost Less Overall
Structural repairs are expensive. You could be forgiven for thinking that DIY will save you money, but this is really not the case. As well as the possibility of a botched DIY job adding expenses, there are hidden costs to trying to do this alone. First, repair products like polyurethane foam and foundation piers are so specialized that they may not be sold in hardware stores.
There is also the matter of getting and using the appropriate equipment. Lifting a single, sunken concrete slab is one feat, but foundation issues are another entirely. These processes require heavy excavation equipment and hydraulic lifting tools to actually make repairs possible. When you calculate the costs that come with hiring the equipment and buying tools, DIY can actually cost more.
Other Problem Signs to Look For
Being aware of common problem signs of structural damage is all-important when it comes to being certain you are dealing with all of the damage that might be affecting your home. Here are some of the problem signs that you should be on the lookout for:
Small, hairline cracks (which are defined as being too thin to fit a credit card into) are perfectly normal in all concrete surfaces and are a sign of the structures settling after construction. Not to be confused with settlement (which is a kind of foundational damage) this is the natural relaxation of the concrete after it has cured in full.
Spreading cracks, by contrast, are far more serious because they tend to be larger, and are still actively growing in size, width, and depth. These are a sign that your property is struggling to cope with immense pressure.
If you find mold and mildew around your home it is time to call a professional. Not only are these formations a sign of dampness and humidity in your home, but they can also be actively harmful to your health and wellbeing. The source of moisture can be found in many places. From structural damage to plumbing leaks, there are dozens of issues that could cause this.
Once it has formed, mold can cause issues of its own. You will recognize mold as patches of discoloration with a slightly fuzzy texture and a musty smell. Some species may cause headaches, migraines, breathlessness, and fainting, so be careful when you approach them.
Seepage and Dampness
If you find pools of water in your home, notice that your walls are wet, or find water in the joint between your wall and flooring, it is likely that seepage is at work in your home. Alternatively, you may notice small cracks that seem to have moisture in them. These can be a result of seepage affecting hairline cracks, of course, but may also be something more serious.
Any cracks that form as a result of hydrostatic pressure will let water seep into your home to wreak havoc. The resulting humidity may even cause your property’s energy efficiency to drop.
Visibly uneven concrete surfaces are a serious warning sign that something has gone wrong in your home. Whether you notice sunken concrete slabs or a bowing wall, this is something you should investigate immediately.
The most likely causes of these issues are unstable soil, foundation damage, lateral movement in the structure of your property, or even invading tree roots.
These problem signs indicate that there are more issues at work in your home than you might have first suspected. If you see them in tandem with pitting, spalling, or stained concrete please contact a professional as quickly as possible to get a repair solution that works for your home.
Choose Indiana Foundation Service for Concrete Lifting
If you have found pitted, stained, flaking, or spalling concrete surfaces around your home, please do not hesitate to reach out to Indiana Foundation Service. We are one of the most highly regarded concrete, basement, and foundation repair firms in Indianapolis, Indiana, and we are always ready to help a homeowner in need. You can reach our team or arrange a free consultation appointment online.
Our experienced and friendly team will send someone to assess your home, identify all of the existing issues, determine the underlying causes, and formulate an effective repair plan. Your inspector will talk you through their findings and suggestions before providing you with a written estimate for all of the costs associated with their solutions. There is no obligation to book with us, so please feel free to take your time and make an informed choice.