The best seal coat for asphalt depends on your surface type and use. Coal tar sealer is the most durable and long-lasting option for heavy-use surfaces. Asphalt emulsion sealer is safer for the environment and better for residential driveways. A professional contractor can recommend the right product for your specific surface.
What are the main types of asphalt sealers?
There are three main types of seal coat products used on asphalt surfaces: coal tar sealer, asphalt emulsion sealer, and acrylic sealer. Each has its own strengths, limitations, and ideal use cases. Understanding the difference helps you choose — or helps your contractor recommend — the right product for your driveway or parking lot.
Coal tar sealer — most durable option
Coal tar sealer is widely considered the most durable and long-lasting seal coat available for asphalt. It offers excellent resistance to gasoline, motor oil, UV rays, and water. Coal tar sealed surfaces typically last 3 to 5 years before needing reapplication, making it a popular choice for commercial parking lots, gas stations, and high-traffic driveways. It dries to a deep black finish and holds up well under heavy vehicle loads.
The main drawback of coal tar sealer is that it contains polycyclic aromatic hydrocarbons (PAHs), which are chemicals that can wash off into waterways and cause environmental harm. Some cities and states have restricted or banned its use. Always check local regulations before using coal tar-based products.
Asphalt emulsion sealer — best for residential use
Asphalt emulsion sealer is made from the same materials as the asphalt itself, making it a more environmentally friendly option than coal tar. It bonds well to the asphalt surface, is safer to handle, and is widely available. For most residential driveways with light to moderate vehicle traffic, asphalt emulsion provides solid protection at a lower environmental cost. It typically lasts 2 to 3 years and needs more frequent reapplication than coal tar products.
Acrylic sealer — best for color and climate extremes
Acrylic sealers are water-based products that offer good UV protection and flexibility in extreme temperatures. They are the most expensive of the three options but hold color well and are environmentally safe. Acrylic sealers are commonly used on decorative or colored asphalt surfaces where appearance is a priority. They are also a good choice in very hot or very cold climates where flexibility is needed to prevent cracking.
Which seal coat is best for a residential driveway?
For most homeowners, asphalt emulsion sealer is the best choice for a residential driveway. It is environmentally safer, easy for professional contractors to work with, bonds well to standard residential asphalt, and provides reliable protection for 2 to 3 years. If you live in an area where coal tar is permitted and you have a high-traffic driveway, coal tar sealer offers longer-lasting protection and may be worth the extra cost.
Which seal coat is best for a commercial parking lot?
Commercial parking lots benefit most from coal tar sealer where it is legally permitted, or a high-grade asphalt emulsion product where coal tar is restricted. Heavy vehicle traffic, oil drips, and constant use demand a sealer that resists chemical breakdown and holds up under pressure. A professional asphalt contractor will assess your lot’s condition, usage level, and local regulations to recommend the most appropriate product.
Frequently Asked Questions
Is coal tar sealer banned everywhere?
No. Coal tar sealer is banned or restricted in some US states and cities due to environmental concerns, but it remains legal and widely used in many areas. Check with your local contractor or municipality to find out what is permitted in your region.
Can I mix different types of sealers?
No. Mixing different sealer types is not recommended. Coal tar and asphalt emulsion products are chemically incompatible and can cause peeling or uneven curing. Always use the same product type for both coats on a surface.
How do I know which sealer my contractor is using?
Always ask your contractor to specify the product name and type before work begins. A reputable asphalt service will be transparent about what they use and explain why it is the right choice for your surface and conditions.
Not sure which sealer is right for your surface? Our local asphalt team will assess your driveway or parking lot and recommend the best product for your budget and conditions — no guesswork, no upselling.