How to Properly Fill a Sinkhole in Your Driveway

Finding a sinkhole forming in your asphalt driveway can be very distressing. Although sinkholes are not usually expensive to repair, it can be very time-consuming and may even signify that there is some underlying structural issue that needs to be addressed. Leaving sinkholes in disrepair makes it easy for water and debris to seep through the surface and lead to structural damage.

Proper driveway installation and care can go a long way toward preventing sinkholes, and those that do form must be addressed right away to minimize damage. Here is a look at what causes sinkholes in asphalt driveways and what you can do about the situation.

Causes of Asphalt Driveway Sinking

When a sinkhole first appears in your driveway, the problem will typically be isolated to just one part of the driveway. If you fail to address it right away, however, it could get worse and spread across more of your driveway, eventually rendering it unusable. What causes sinkholes to form? Here is a look at some of the most common causes.

Poor Installation

One of the biggest causes of asphalt driveway sinking is poor installation. Some building contractors may be inexperienced or try to cut corners to save costs while installing a new asphalt driveway. Rushing the job or using low-cost materials can result in an inferior finished product.

The proper method of installation entails laying a solid foundation and compacting it to ensure that it is secured in place before proceeding with the paving. Skipping this step or using an inappropriate base can weaken your driveway’s structural integrity.

Severe Internal Water Damage

When water penetrates the surface of an asphalt driveway, it can lead to the expansion and contraction of the internal aggregate at different temperatures. This can eventually cause internal cracking that may take years to build up before it becomes apparent above the ground. In other words, you may not know that internal cracking is occurring until you see the beginnings of a sinkhole forming.

Instability

Another potential cause of sinkholes is instability in the ground. This could be due to geological activity in the area, construction work nearby, animal burrows, or unfavorable weather conditions. Significant soil erosion and drainage problems may also lead to damage to an asphalt driveway’s internal structure and cause it to become unstable.

Drainage Issues

Drainage systems that do not correctly move precipitation such as rainwater and melted snow away from the driveway can cause it to be absorbed by the asphalt and lead to the type of expansion and contraction that can cause sinkholes and potholes to form.

Fixing an Asphalt Sinkhole

The best course of action when you notice a sinkhole forming in an asphalt driveway is contacting driveway contractors and having them evaluate the damage. Because sinkholes can be caused by structural issues, it may be necessary to address the cause before repairing the sinkhole.

However, if you are dealing with a minor asphalt sinkhole and you are eager to try to fix it yourself, there are a few techniques you can try. Because of the manner in which sinkholes are formed, it is not possible to repair them completely using the surface patching that might work in a pothole. Instead, sinkholes need some reinforcement from below.

First, you need to remove the part of your driveway where the sinkhole has appeared in order to access its internal structure. Then, clean the area out carefully, taking care to extract all of the standing water, tree branches, broken asphalt and other debris you encounter.

Next, you will need to lay a foundation. This may either be a hot or cold asphalt mixture or hard stone – choose whichever method was used when your driveway was initially installed for the best results. Compact the aggregate once you have laid it to secure it in place. Then, you will need to lay new asphalt on top of it.

You could also use pressure grouting, which is also known as compaction grouting or permeation. In this process, you will inject a cement-like mixture into the ground in order to fill the void securely without needing to remove the ground surface. This is a quicker and less invasive method of repair, and it may come with the added benefit of the injected grout potentially making its way into other voids nearby that you are not aware of that may eventually cause sinkholes of their own.

Another option is to use a cold patch mixture from your local home improvement center, but keep in mind that this is just a temporary solution, and it will eventually be necessary to call in professionals to deal with the problem.

Caring For Your Asphalt Driveway

Sinkholes are not the only problems that can affect gravel driveways; they are also prone to cracking, deterioration and damage caused by vegetation. Here are some tips for caring for your asphalt driveway to prevent other types of damage from occurring.

Fill Cracks Immediately

Cracks may appear in your asphalt driveway due to movement in its base or subsoil in a freeze-thaw cycle. Water seeping beneath the driveway due to excessive rain can also cause movement. It is important to keep all of the cracks in your driveway filled and ensure the driveway is properly coated. Home improvement stores sell products that are specially formulated to repair small driveway cracks.

Clean Spills

As an oil-based material, asphalt is prone to damage from many types of spills. Oil and gas spills can cause the surface of the driveway to dissolve and lead to deterioration. Take measures to prevent these materials from leaking or spilling, and clean up any spills that do occur with absorbent materials right away to minimize damage.

Stay on Top of Weeds

Weeds, grass and other vegetation can push through asphalt, so use spot killer to address any vegetation that starts to pop up before it becomes a major problem.

Contact the Residential Asphalt Paving Experts

Sinkholes are often an indication of a more serious problem that could put your driveway or home at risk. If your driveway is experiencing sinkholes or other issues, reach out to the residential driveway professionals at Dirt Connections in Northern Virginia. Our team will assess the damage and help you find an effective and affordable solution.