Key Takeaways
- Sealcoating protects asphalt from UV rays, water, and chemicals, which helps extend the surface’s lifespan and maintain its appearance.
- Adhering to safety practices during asphalt sealcoating is essential to minimize health risks, including exposure to harmful fumes and physical hazards.
- While sealcoating helps reduce surface wear and adds a layer of protection, it cannot stop the inevitable cracking that occurs over time due to natural aging and external stress factors.
What Is Sealcoating?
Sealcoating is a protective layer applied to asphalt surfaces to shield them from elements such as water, oil, and UV rays. It helps maintain asphalt surfaces and slow down their degradation by providing a protective barrier, minimizing the need for frequent repairs. The sealcoating process fills minor surface voids, reducing exposure to air and sunlight, which can degrade the asphalt over time.
What Is Sealcoating Made Of?
Sealcoating is made of a combination of different materials designed to protect and enhance the surface of asphalt pavement. The primary ingredients used in sealcoating mixtures include asphalt emulsion, fillers, water, and additives.
Asphalt sealcoating comes in various types, each designed to offer specific benefits based on the materials used and the environment where it’s applied. The most common types include:
- Coal Tar Sealers: These are made from coal tar pitch and are known for their durability and superior resistance to oil, gasoline, and UV rays. Coal tar sealers form a tough protective layer over asphalt, making them ideal for high-traffic areas like parking lots. However, they can emit a strong odor during application.
- Asphalt Emulsion Sealers: Made from petroleum-based asphalt, this type of sealer is more eco-friendly than coal tar and has a lower odor. Asphalt emulsion sealers offer good protection against water and UV damage, but they may not be as resistant to oil or gasoline as coal tar. They are often preferred for residential driveways due to their ease of application and more natural look.
- Acrylic Sealers: These are synthetic and water-based sealers that provide excellent protection against UV rays and weathering. Acrylic sealers are the most expensive option but offer longer-lasting results and are available in a variety of colors. They're typically used in decorative applications, like walkways or sports courts, where appearance is as important as protection.
- Oil-Based Sealers: Contain petroleum-based products and provide better resistance to oils and gasoline spills, ideal for restoring older asphalt. However, while effective, oil-based sealers take longer to dry and release more volatile organic compounds (VOCs). These sealers penetrate deeply into asphalt, restoring flexibility and prolonging the life of aged, brittle surfaces.
- Fast Dry Sealers: Utilizes additives to significantly reduce drying time, fast-dry sealers allow traffic to return to the surface within hours, making them ideal for commercial areas with high use. This is beneficial for high-traffic areas that require minimal downtime. However, they may not last as long as other sealers and may result in the need for more frequent reapplications.
When Do You Need Asphalt Sealcoating?
Asphalt sealcoating should be applied when an asphalt surface begins to show signs of wear, such as fading color, cracks, or exposure to harsh weather conditions. It is recommended to apply sealcoating every 2 to 3 years, depending on the level of traffic and environmental factors.
| Asphalt Sealcoating Pros | Asphalt Sealcoating Cons |
| Protects from weather damage | Requires periodic reapplication |
| Enhances appearance | Can be costly in the long run |
| Prolongs asphalt life | Must be applied during dry weather only |
Is Sealcoating Asphalt Actually Effective?
Yes, sealcoating is highly effective in preserving asphalt surfaces. It helps resist the effects of oxidation, chemical spills, and daily wear and tear. However, its effectiveness depends on factors such as surface preparation, weather conditions during application, and the quality of the sealer used.
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What is the Ste-by-Step Asphalt Sealing Process?
Asphalt sealing involves a series of critical steps to protect and preserve the asphalt surface, whether it's a parking lot, roadway, or commercial driveway. Below is a detailed guide to the asphalt sealing process:
Step 1: Surface Inspection and Preparation
Before starting, conduct a thorough inspection of the asphalt surface to identify any areas needing repairs, such as cracks, potholes, or oil stains. Repairs must be made before the sealant is applied to avoid further damage.
Workers will clear the surface of debris, dirt, and loose materials using high-powered blowers, sweepers, or pressure washers. This step is key to ensuring that the surface is clean and ready for sealant application.
Step 2: Cleaning and Oil Spot Treatment
Oil and gas spills are common on asphalt, especially in parking lots or areas with high vehicle traffic. These petroleum stains must be treated with a special oil spot primer or degreaser to prevent the sealant from failing to adhere to those spots. The cleaning process is rigorous, often involving mechanical scrubbers and environmentally safe degreasers to lift stains that have seeped deep into the asphalt.
Step 3: Crack Filling and Repair
Cracks in asphalt are sealed with specialized crack fillers to prevent water penetration, which can erode the foundation beneath the asphalt. For smaller cracks, hot rubberized crack filler is typically used, while larger cracks or potholes may require asphalt patching.
This step is crucial to maintaining the structural integrity of the surface and preventing further damage from temperature changes and water infiltration.
Step 4: Sealant Mixing and Preparation
Before application, the sealcoating material is mixed in accordance with manufacturer specifications. The right balance of additives, sand, and water ensures the sealant performs optimally. Professional-grade mixing machines or trucks are used to maintain consistency and achieve an even application.
Step 5: Application of Sealant
The sealcoating is applied using specialized equipment, either through a spray system or a squeegee machine. For large areas like parking lots, spraying is often the preferred method as it allows for quick, even coverage over vast surfaces.
Workers may use squeegees for smaller or more detailed areas to ensure precision. Typically, two coats of sealant are applied for maximum durability, with the second coat applied only after the first has dried sufficiently.
Step 6: Curing and Drying Time
After the sealant has been applied, it must be given adequate time to dry and cure before the asphalt can be reopened to traffic. Curing time varies depending on the type of sealant and weather conditions, with warm, dry days speeding up the process. In most cases, the surface will need to remain closed for 24 to 48 hours to allow the sealcoating to set properly.
Step 7: Restriping and Marking (Optional)
If the sealcoating is applied to areas with parking spaces, roadways, or other marked sections, the final step involves restriping the surface once the sealant has fully cured. High-quality traffic paint is used to reapply any necessary lines or symbols, such as crosswalks or parking spaces. This step helps restore the surface to its functional state while enhancing its appearance.
Step 8: Final Cleanup
Once the sealcoating process is complete and the surface has dried, the final cleanup involves removing equipment and debris from the site. Proper disposal of leftover materials, especially sealants and cleaning chemicals, is necessary to avoid environmental contamination. Safety signs and barriers are then removed to reopen the area to regular use.
How much does sealcoating cost?
The cost of sealcoating typically ranges from $0.15 to $0.25 per square foot. For residential driveways, this usually amounts to between $250 and $500, depending on the size of the area. Larger commercial projects may incur higher costs due to increased surface area and additional labor requirements.
Prices can vary based on location, materials, and contractor rates. Always consult with a professional for an accurate estimate specific to your project and region.
Health and Safety Risks Associated with Sealcoating
Like many industrial processes, asphalt sealcoating carries potential health and safety risks that should be carefully managed. Below are some of the key risks:
- Exposure to Hazardous Chemicals: Sealcoating products, particularly coal-tar-based, can contain harmful chemicals like PAHs, which pose long-term health risks through inhalation or skin contact.
- Inhalation of Fumes and Dust: The application of sealcoat releases fumes that can cause respiratory irritation, headaches, or dizziness if inhaled without proper ventilation.
- Risk of Fire and Explosion: Sealcoating products containing volatile organic compounds (VOCs) can be flammable, increasing the risk of fire or explosions near open flames.
- Skin and Eye Irritation: Direct contact with sealcoat can cause skin irritation, burns, or eye injuries if protective gear like gloves or goggles is not worn.
- Heat Stress: Working in hot environments during sealcoating can lead to heat-related illnesses, such as heat exhaustion or heat stroke.
- Slips, Trips, and Falls: Wet sealcoat creates slippery surfaces, increasing the risk of falls if workers do not take precautions.
- Environmental Risks: Improper application or disposal of sealcoating materials can lead to environmental contamination and harm local ecosystems.
Do You Have to Wear a Respirator During Asphalt Sealing?
Yes, respirators are often recommended during asphalt sealcoating due to the risk of inhaling fumes from the sealant, especially when applying coal tar-based products, which emit harmful VOCs. The use of a respirator can prevent long-term respiratory issues for workers.
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Asphalt Sealcoating Safety Practices
Safety should always be a top priority when sealcoating a driveway or any asphalt surface. Key practices include:
Wear Protective Gear
Workers must wear proper personal protective equipment such as gloves, long sleeves, and safety goggles to prevent direct contact with the sealant, which can cause skin irritation or eye damage. Respirators may also be necessary to avoid inhaling harmful fumes during application, especially when using coal tar-based sealants. Proper footwear is essential for preventing burns or injuries caused by the hot materials used in the process.
Use a First-Aid Kit
A well-stocked first-aid kit should always be accessible on site. In the event of minor injuries such as burns, cuts, or chemical splashes, immediate treatment can prevent complications. Workers should be trained on how to use the first-aid kit and respond to common job-related injuries.
Bring a Fire Extinguisher
Since some sealants are flammable, having a fire extinguisher readily available is important for quickly addressing any fires that may break out during the asphalt sealing process. Hot sealant or equipment malfunctions could pose a fire risk, so a fire extinguisher can prevent these incidents from escalating. Workers should also be trained in using the extinguisher and aware of the fire hazards involved.
Have an Eye Wash Kit
If sealant splashes into the eyes, an eye wash kit provides immediate relief by flushing out harmful chemicals. Prompt use of the eye wash station or portable kit can prevent more serious damage to the eyes. It is important to keep the kit in an easily accessible location during the asphalt sealing process.
Use Barricades and Signs
Setting up barricades and warning signs around the work area is necessary to keep unauthorized personnel and vehicles away. This practice not only protects the sealcoating surface but also prevents accidents involving pedestrians or drivers entering the area before the sealant has dried. Clear signage helps ensure safety and minimizes potential liability.
Be Careful with Rain
Asphalt sealing should not be performed if rain is expected, as moisture can interfere with the application process and cause the sealant to wash away before it sets. If rain begins during application, work should stop immediately, and measures should be taken to protect the freshly applied sealant. Rain can compromise the quality of the sealcoating, leading to uneven surfaces and the need for reapplication.
Implementing safety precautions helps prevent accidents that could disrupt the asphalt sealing process, such as injuries from improper handling of materials or equipment failures. Not only does this protect workers, but it also leads to a more efficient and effective application and reduces the risk of costly delays and liability issues.
Asphalt Sealcoating FAQs
Is sealcoating safe?
Yes, sealcoating is safe when proper safety precautions are followed. Workers should use protective gear, ensure proper ventilation, and handle materials according to safety guidelines to minimize health and environmental risks.
How long does sealcoating take to dry?
On average, sealcoating takes 24 to 48 hours to dry, depending on the weather conditions and the type of sealant used. Warmer, dry weather speeds up the drying process.
Can you put sealcoating over concrete?
No, sealcoating is not recommended for concrete surfaces. Sealcoating is specifically designed for asphalt and does not bond well to concrete. Concrete has a different composition and requires other types of sealants designed for its properties, such as acrylic or epoxy-based sealers, which are better suited for protecting and maintaining concrete surfaces.
What happens if it rains after sealcoating?
Rain can wash away the freshly applied sealcoating, causing uneven surfaces or failure of the sealant to adhere properly. If rain is expected, it's best to delay the application to avoid compromising the project.
How long does sealcoating last?
A properly applied sealcoating layer can last between 2 to 3 years. The longevity depends on factors such as traffic volume, weather conditions, and the quality of the sealant.