The Ultimate Guide to Asphalt Crack Repair

The Ultimate Guide to Asphalt Crack Repair

Asphalt cracks are ugly, but they are also inevitable as the surface ages. Once the crevices form you need to repair them quickly before they grow into potholes or other, more significant issues. Cracks can spread and grow quickly, so you want to address the issue as soon as you can to prevent more difficult and expensive repairs. 

Fixing cracks in asphalt is not extremely difficult, but you do need to know how to do so properly including the best time to repair cracks, how to prepare the surface, and what tools to use. But first, it is a good idea to know what causes cracks, crevices, and separation in the first place. 

Why Asphalt Cracks Form

It’s important to know the causes of asphalt cracking because it can help you prevent rapid formation of cracks in the future. Plus, when you fix asphalt cracks, you want the repairs to last. Some of the common causes are excessive stress, extreme temperatures, improper installation, and accumulating moisture. 

asphalt industrial asphalt cracks 

Age and Stress

As your asphalt gets older, it gets weaker. While the weakening process takes a lot of time, stress factors can increase the likelihood of deterioration or damage. Over a prolonged period, the gradual damage caused by normal use can cause crevices and cracks to form. 

Heavy vehicles can put a lot of stress onto the surface and contribute to crack formation. This is most commonly a problem with extremely heavy vehicles, but can also happen with heavy use areas like parking lots or any public access areas that use asphalt. In fact, it can even happen with private driveways with use over a long enough period. Tree roots can also infiltrate the asphalt or cause shifting that compromises the integrity of the construction.

Sunlight and High Temperatures 

When the sun warms up an asphalt surface, it dries it out. When this happens, the materials break down and become brittle. Brittle asphalt means that the construction loses its flexibility and strength, which can make it more likely that damage, including cracks, can develop. 

High quality asphalt material is less likely to become damaged by the sun, so it is always important to choose paving material that is made to withstand extreme elements and heavy sunlight, especially during hot Summer months. 

Improper Installation

Poor installation of asphalt can cause significant issues, including cracks. There are many different aspects of installation that can contribute to these types of failures. Inexpensive and low quality materials can break down or deteriorate faster because they expand, contract, and lack the resilience of higher quality options. 

Other common issues with installation are layers of asphalt that are too thick or too thin and poor blending of the asphalt mixture. These things can weaken the entire surface so that it becomes more susceptible to damage caused by normal stressors like foot and vehicle traffic and natural expansion and contraction.  

Moisture and Freezing Temperatures 

Moisture can also weaken asphalt because it can wash away material and slowly erode the surface, especially with heavy rains or harsh moisture conditions.  Moisture can also penetrate the surface and work its way into smaller fissures. When this happens, the pressure between the separation can apply too much force and cause these small crevices to grow into larger cracks. 

When moisture finds its way into and around asphalt during cold weather, it can freeze. When water freezes it naturally expands. This can cause even more pressure that can damage the asphalt and contribute to worsening cracks and deterioration. 

Best Time to Fix Cracks

It is best to repair asphalt cracks as soon as they develop because procrastinating can mean plant and weed growth in the cracks, lasting damage, more water infiltration, and growing length and width. This all contributes to repairs or replacements that cost substantially more. 

However, you also want to make sure that there is no freezing weather coming up too soon, especially if there is a chance of moisture. Try to prepare for a few dry days during and after asphalt crack repair to ensure that moisture or extreme temperatures do not harm your work. 

Prepping for Crack Filling

Before you begin the process of filling asphalt cracks, you need to prep the area and prepare for the type of repairs. While these procedures are easy to do, they are a critical part of the work and should never be skipped. 

asphalt industrial asphalt road cracks

Eliminate Debris

The first thing you need to do is to eliminate all debris within the asphalt cracks. Debris includes rocks, vegetation, pieces of asphalt, roots, or dropped objects. You need to get all of that debris out of the fissures using a paint scraper or even a screwdriver. You can also use a broom to sweep out any remaining dust or small debris. 

If there is grass or weeds growing inside the crevices, then you need to pull them out by the roots. If this isn’t possible, then you can pour a small amount of vinegar onto them to kill them. Just make sure you remove any leaves and other vegetation that may have fallen off the weeds into the opening of the asphalt.  

Keep it Dry 

Before you can fix asphalt cracks, you want to ensure that the surface is thoroughly dry. Skipping this step could mean an entirely failed repair process. This is why you shouldn’t use a pressure washer to clean up the cracks, but if you do you still have to make sure you give it enough time to dry completely before moving on to the next steps of the repair project. 

Examine the Crack Size

While you are eliminating debris, you can inspect the size of the cracks, which will determine the best way to address the crack repair job. You don’t need to measure specifically, but there are three types of cracks depending on size. Each size is fixed in a different way. You also want to examine the asphalt for spidering damage, which can indicate brittle materials that need sealcoat application. 

Shallow cracks are the easiest to fix and are less than a half an inch in depth. If you began the repair process as soon as you noticed the cracks, then there is a good chance that they are still at this stage. Deeper cracks are more developed and there is an extra step when they are over a half inch deep. It is necessary to fill them with sand until they reach the depth of shallow cracks (about a half inch) before you repair them. 

Best Ways to Repair Asphalt Cracks

There are two main methods that you can use to repair asphalt cracks depending on the severity of the problem and the equipment you have available. The two types are cold crack filler and hot rubberized crack filler. In addition to the two main methods, there are additional strategies and other ways to repair asphalt cracks that are possible using these two types of filler. 

Cold Pour Crack Filler

Cold crack filler is an effective, but simple method that is preferable for DIY asphalt crack repair. This is because it does not need to be heated for installation, which means it doesn’t take in-depth knowledge or expensive tools. 

There are two primary types of cold pour crack filler. Tube crack filler comes in a tube, as the name suggests, which means it requires a caulk gun. Pour crack filler does not require a caulk gun or any other additional equipment, but may be harder to control for some homeowners who are repairing asphalt cracks for the first time. 

To apply, you will first need to shake the bottle and fill the crack as flush and uniform as possible with the placement surrounding the crack. Then, use a squeegee or trowel on the portion that you filled. Next, you have to  allow the crack seal to dry, which can take up to 24 hours. After 24 hours, If the crack filler dips down too much after completely drying, then you may need to add a second layer to ensure that the surface is uniform and even.

While this option is easy and great for homeowners to fix driveways, it is ineffective for large cracks and crevices. It can fall into larger fissures and sink, which means that the crack never gets fully sealed. It can also cause the asphalt surface to be uneven. 

asphalt industrial asphalt road crack filled

asphalt crack filling machine in use

Hot Pour Crack Filler

Hot pour crack repair requires you to heat up the materials to fill cracks. This offers faster set times and the ability to use it as soon as the rubberized crack filler cools down. While this can give a professional appearance and exceptional functionality because it does not shrink, the project will also involve a crack repair machine to heat up the filler and apply it to the surface. 

To apply this, you will have to melt the rubberized crack filler in the crack filling machine. Then, you can use the machine to fill the cracks once it is fully melted. Just make sure to fill all crevices and corners. When you are applying the crack filler, you need to fill above the surface level. While this may seem to be too full, you need to pack it down until it is fully compressed after the initial application. 

While it is not as easy as using a crack filling machine, you can apply melt-in filler with a propane torch and extension hose. It will cost less, but for wider or longer cracks will be more difficult and time consuming. Still, it offers a balance between the ease of cold pour crack filler and the durability of hot pour crack filler. 

Tools Needed

While cold pour crack filler requires minimal tools, if you choose hot pour crack filler, then you will need the right equipment. Choosing the best crack filling machine is critical to the success of your project and the integrity of the asphalt. There are plenty of options, but knowing what the superior choices offer is necessary to make the best selection for your specific project or purpose. 


This RynoWorx crack fill machine is not only effective but efficient and easy to use. In fact, you can even repair up to 400 feet of cracks in a single hour! Not only that, but it has a durable construction made out of solid, powder-coated steel. 

With additional features like a fuel regulator, glycerine-filled thermometer, and forged steel axles, you can precisely maneuver the machine with expert control and ensure reliable projects every time. This model is perfect for a smooth application process and more uniform results for highly effective asphalt crack repair. 

rynoworx RY10MA-V3 base model crack fill melter

pavemade hotbox 10 crack fill melter


For precise applications using a machine that can withstand the most abusive job sites, you cannot go wrong with this Pavemade Hotbox 10 machine. It comes with a lifetime warranty on the melter body and the design is sturdy, but still easy to control with speed to get the job done both effectively and efficiently. In fact, this option is easy to use even if you are a DIY homeowner and have never filled asphalt cracks before. 

With a 10 gallon capacity, it is excellent for small and large jobs alike and it also has steel wheels that are made to resist the accumulation of materials. The wheels have ball bearings for smooth pushing, making this machine easy to use even if you are tired from a hard day of work. You can’t go wrong with this option as a contractor or homeowner.


If you want a budget-friendly option or just have a smaller job, but still want a superior product for ease of use and effective crack repair, then the Gingway 10 Gallon Mini Melter Applicator is a superb choice. It is efficient and can heat the material in 20 minutes or less so you can get to work and be done with the job faster. 

It has a wide range of useful features including an accurate temperature gauge, a platform to hold a propane bottle, and a lightweight design for easy mobility between sections of the asphalt surface. 

gingway 10 gallon mini crack fill melter applicator


Asphalt crack repair is not difficult, but there are steps you need to take to ensure that the job is done correctly. Identifying the cause and prepping the area properly are both essential to a project’s success. Then, you need to decide whether you want to use cold pour or hot pour crack filler and gather the necessary equipment before proceeding to effectively repair the asphalt surface. Good luck with your project! 



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