5 Common Mistakes in Crack Sealing Prep (and How to Avoid Them)
When it comes to pavement maintenance, crack sealing is one of the most cost-effective ways to extend the life of roads, driveways, and parking lots. But there’s a catch: even the best sealant can fail if the surface isn’t prepared correctly.
Preparation is the foundation of successful crack sealing—it ensures the sealant adheres properly, cures evenly, and protects the pavement from further damage. Unfortunately, contractors sometimes cut corners or make small errors that lead to costly failures and repeat work.
Below are 5 common mistakes in crack sealing prep—and, most importantly, how to avoid them:
1. Leaving Moisture in the Crack
One of the most frequent causes of sealant failure is sealing over damp cracks. Even a small amount of moisture trapped in the crack can prevent the sealant from bonding properly, leading to early failure when water seeps underneath the repair.
This issue is especially common after overnight dew, rainfall, or in the cooler, damp mornings typical in late summer and fall. Crews might assume a crack “looks dry enough” and rush to seal it, only to find the repair fails within months.
How to avoid it:
Use a Hot Air Lance to dry cracks completely before applying sealant. Unlike a torch that relies on an open flame, LAB’s flame-free Hot Air Lance delivers high-velocity, superheated air that penetrates deep into the crack, evaporating moisture quickly and thoroughly. This ensures a dry, ready-to-seal surface, even in damp or cool conditions, so crews don’t lose productivity after rain or heavy dew.
2. Inadequate Cleaning of Debris and Dust
Another common mistake is failing to remove all the debris, dust, or loose materials in the crack. Sealant needs to bond directly to clean, solid pavement—but any leftover dirt acts as a barrier.
A crack that hasn’t been properly cleaned can look fine at first, but once exposed to traffic, weather, and temperature cycles, the sealant bond can fail, allowing water infiltration and further damage.
How to avoid it:
Proper cleaning is non-negotiable. The LAB Hot Air Lance excels here by combining powerful airflow and heat to clear out dust, loose aggregate, vegetation, and other debris. Instead of using separate blowers or brushes, operators can handle cleaning and drying in one pass, saving time and ensuring a perfectly prepped surface every time.
3. Using the Wrong Equipment or Tools
Many contractors still rely on outdated or fragmented methods: open-flame torches for drying, blowers for cleaning, wire brushes for scrubbing, and routers for shaping. While these can work, they create inefficiencies, safety risks, and inconsistent results.
Open flames, in particular, can be dangerous on busy job sites—risking fires, uneven heating, and compliance headaches. Meanwhile, moving between multiple machines takes extra time, labor, and increases opportunities for mistakes.
How to avoid it:
Switch to a single, integrated solution. LAB’s Hot Air Lance eliminates the need for multiple tools. With its patented flame-free combustion system, it delivers consistent, even heat without fire risk. It also clears and dries cracks simultaneously, reducing labor, simplifying training, and improving overall safety on the job.
4. Skipping Temperature Considerations
Many crews underestimate how much ambient temperature affects crack sealing. In cool or damp weather, pavement retains moisture longer, and sealant won’t bond well to a cold surface. Applying sealant in these conditions without adjusting prep can lead to poor adhesion and early failure.
It’s especially tempting to rush during busy fall schedules or after weather delays—but failing to properly preheat the crack just sets the stage for callbacks and costly repairs later.
How to avoid it:
A Hot Air Lance is specifically designed to address this problem. Its adjustable temperature and air volume controls let operators tailor heat output to match conditions, ensuring a warm, dry, debris-free crack even on chilly mornings. This flexibility extends the sealing season into cooler months and ensures consistent quality across varying job sites.
5. Rushing Through Preparation to Save Time
When schedules are tight and crews are under pressure to finish quickly, it’s easy to rush through prep work. Skipping steps or hurrying cleaning and drying can lead to superficial prep that looks fine initially—but results in sealant failure down the line.
A failed seal means expensive rework, lost time, and disappointed clients—hurting both the bottom line and the company’s reputation.
How to avoid it:
Using the LAB Hot Air Lance streamlines the process without cutting corners. By combining cleaning, drying, and preheating into one step, it lets crews work faster without sacrificing quality. It’s lightweight, easy to maneuver, and designed for all-day reliability, so operators can maintain a consistent pace without skipping critical prep work.
Prep Right, Seal Better with LAB’s Hot Air Lance
Avoiding these common mistakes isn’t just about doing the job “by the book”—it’s about delivering longer-lasting repairs, reducing costly callbacks, and protecting your reputation.
LAB Manufacturing’s Hot Air Lances are engineered to make this easy. Proudly made in the USA, they offer contractors a safer, more efficient, and highly effective way to prepare cracks for sealing—no open flames, no extra tools, no wasted time.
Get the job done right the first time.
Explore LAB Manufacturing’s Hot Air Lances today and see how you can transform your crack sealing process.
