“Crack sealing” and “crack filling” are often used interchangeably, but they describe two different repair methods that use different materials for two different types of cracks. Using the wrong one not only wastes money, but it can also mean redoing the repair within a single season. Here is how to tell them apart and know which one a specific crack actually needs.
What Is Crack Sealing?
Crack sealing uses a hot, rubberized asphalt sealant that is heated to a liquid state and applied directly into a routed or cleaned crack. As it cools, it forms a flexible, adhesive bond that expands and contracts along with the pavement as temperatures change throughout the year.
- Best suited for: active or “working” cracks, meaning cracks that visibly widen and narrow as the pavement expands and contracts with the seasons.
- Material behavior: highly flexible, designed specifically to move with the crack rather than crack or separate from it.
- Typical service life: properly applied crack sealant commonly lasts several years before requiring reapplication, depending on traffic volume and climate exposure.
- Application process: the crack is typically routed (slightly widened with a specialized tool) and cleaned of debris before the hot sealant is applied, thereby improving adhesion and performance.
What Is Crack Filling?
Crack filling uses a less flexible, generally less expensive material, often a cold-applied asphalt emulsion or rubberized filler, which is poured or applied directly into the crack, without the routing step that crack sealing typically involves.
- Best suited for: non-working or stable cracks, meaning cracks that are not actively moving with temperature changes, often because they have already stabilized or are located in a lower-stress area of the pavement.
- Material behavior: less flexible than rubberized sealant, which means it is more prone to cracking or pulling away from the pavement if applied to a crack that continues to move.
- Typical service life: generally shorter than crack sealing when used appropriately, and significantly shorter than that if used on a working crack it was not designed for.
- Application process: simpler and faster than crack sealing, since it typically skips the routing step, which is part of why it costs less.
How to Tell Which Type of Crack You Have
- Working cracks typically appear on pavement less than three years old, run in irregular or map-like patterns, and visibly change width between summer and winter. Most Wisconsin parking lot cracks fall into this category, given how dramatically temperatures here swing between seasons.
- Non-working cracks are typically found in older pavement where the surrounding asphalt has already stabilized, run in straighter, more predictable patterns (such as along a paving seam), and show little to no visible width change across seasons.
A contractor experienced with Wisconsin pavement can typically identify which category a given crack falls into during a routine site visit, without needing specialized testing equipment.
Why the Distinction Affects Your Return on Investment
Crack sealing costs more upfront than crack filling, largely due to the routing step and the specialized hot-application equipment involved. But it is designed to withstand the exact conditions that cause cracking in the first place: temperature-driven expansion and contraction. For a commercial property, building a maintenance budget that pays for the repair method that actually matches the problem, rather than defaulting to the cheaper option, is almost always the better long-term investment.
- Sealed cracks keep water out of the sub-base far more effectively over time, which protects the pavement’s underlying structure, not just its surface appearance.
- A crack filled with the wrong material may need to be redone within a year or two, meaning the cheaper initial repair ends up costing more in total labor and material over time.
- Untreated or improperly treated cracks allow water infiltration, accelerating freeze-thaw damage, the leading cause of pothole formation in Wisconsin.
When Crack Filling Is Still the Right Choice
Crack filling is not simply an inferior option. For genuinely stable, non-working cracks, particularly on a lower-traffic area of a property or a lot approaching the end of its service life before a planned resurfacing, crack filling can be a cost-effective way to slow water infiltration without the added expense of full crack sealing. The key is to match the method to the crack, not to default to whichever is cheaper across the board.
Best Timing for Crack Repair
In Wisconsin, spring and fall are generally the best windows for crack sealing and filling. Cracks are often most visible and accessible after winter, and completing the repair before the heaviest freeze-thaw cycling resumes helps the material perform as intended. Waiting until a crack has widened significantly reduces the effectiveness of either method and often pushes the repair into more expensive territory, such as full-depth patching.
Frequently Asked Questions
Can crack filling be upgraded to crack sealing later?
In many cases, yes, a previously filled crack can later be properly sealed if it turns out to be an active, working crack. It is generally more cost-effective to correctly identify the crack type at the outset than to repair it twice.
How long does each repair take to cure?
Crack sealant typically cools and sets within a short window, often allowing traffic to resume within an hour under normal conditions, though this varies with temperature and humidity. Crack filler generally cures on a similar or slightly faster timeline. Your contractor can confirm the specific timeline for your project and weather conditions.
Is crack sealing or filling a substitute for sealcoating?
No. Crack repair addresses individual cracks, while sealcoating protects the entire pavement surface from oxidation and water penetration. The two are complementary and are often performed together as part of a routine maintenance schedule.
Not sure which approach your pavement needs? Contact American Pavement Solutions, or learn more about our crack sealing services.