by Marvin Joles
If I could show you my DMs (don’t worry, nothing to hide here), you would likely be surprised by the amount of sealcoating questions I field. It’s quite a lot. I imagine the only people who may get more questions about this topic are the manufacturers … maybe. I answer every single one, even if it consumes a good chunk of my time. I figure they come here because they aren’t getting the responses they are looking for in their previous searches.
In a continuous effort to help minimize the time spent on this subject while leaving out major brand names, I hope to shed some light on what the three major sealer types are (I know there will be an argument for gilsonite), what they are made of and how to apply them.
Let’s get into it. Each have distinct compositions and application methods, tailored to protect asphalt surfaces from wear, weather and chemical damage.
Coal-Tar Based Sealer:
Composition: Derived from coal tar and a byproduct of coal processing, these sealers are mixed with water, silica sand and additives like polymers for enhanced durability. They often include emulsifying agents to maintain a stable mixture.
Application: Applied in a thin layer or two, using a squeegee, spray system or brush. The surface must be clean and dry, with cracks filled beforehand. Application usually requires good weather (warmer than 50°F, no rain forecast for 24-48 hours) but coal tar has a good reputation for performing well later in the year when temps drop some. Curing takes 24-48 hours, during which the area should be coned off to prevent traffic.
Notes: Known for resistance to oil and gas, and its performance under trees and UV damage, coal tar sealers are durable but have a strong odor, can burn skin and hold environmental concerns due to volatile organic compounds (VOCs).
Asphalt Emulsion Sealers
Composition: Made from asphalt (bitumen) and emulsified in water, combined with fillers like sand or clay, and additives for flexibility and adhesion. They contain fewer VOCs than coal tar sealers.
Application: Similar to coal tar, AE is applied with a squeegee, spray or brush, in one to two coats. The pavement must be cleaned, and cracks repaired prior. Curing typically takes 24-36 hours under dry, warm conditions (warmer than 50°F). Spray systems are common for larger areas due to ease and speed. This sealer has been known to be finicky under trees, cool conditions and excess ground moisture.
Notes: These are more environmentally friendly and easier to apply than coal tar but may offer less resistance to oil and gas spills, but the “non skin burn” is the real win for me and my crew.
Acrylic Sealers
Composition: Made from acrylic polymers, suspended in a water-based solution, often fortified with additives for UV resistance and durability. They may include sand for texture or fast-drying agents. This is likely the most technical sealer of them all.
Application: Applied in thin coats (one to two layers) using a sprayer or roller after thorough surface cleaning and crack repair. They dry faster than other sealers (often within 4–8 hours) but require warm, dry conditions. Not suitable for squeegee application due to their thinner consistency.
Notes: Acrylic sealers are premium, offering excellent UV protection and a glossy finish, but they are more expensive and less resistant to oil stains compared to coal tar.
Okay, okay. I’ll talk about gilsonite briefly and what I know about it. In all transparency, I have used this sealer before, very early in my career, and honestly loved applying it. But as my business scaled, it just wasn’t feasible to build a solid business around it where I live, due to it being banned locally.
Gilsonite Sealers
Composition: Gilsonite sealer is primarily composed of gilsonite, a naturally occurring, resinous hydrocarbon (natural asphaltite) mined predominantly in the Uinta Basin of Utah. It is blended with a compatible carrier solvent, such as mineral spirits, to create a fluid product.
Application: Gilsonite sealer is usually applied using a roller or spray equipment. Apply thinly to avoid puddling, ensuring a uniform coat. For best results, apply when temperatures are moderate, and avoid application during rain or freezing conditions, as the sealer is less affected by weather compared to water-based alternatives but still requires proper drying.
Drying time is approximately 2-4 hours under optimal conditions, but no vehicle traffic should be allowed for at least 24 hours to ensure proper curing.
Notes: Gilsonite sealer is particularly effective for rejuvenating older asphalt (5-10 years old) by softening and blending with the existing binder, though some sources suggest it performs best on newer asphalt for deeper penetration. It provides a glossy, jet-black finish, enhancing aesthetics while protecting against oxidation, moisture and frost damage.
I really hope this helps you get a frame of reference and answers any general questions you have about the major asphalt sealers in our industry. I should mention that it is best practice to always follow manufacturer instructions for specific products and local environmental regulations.
As always, if you have any questions, insight or criticisms about this article or anything in it, please feel free to email me at marvinjoles@gmail.com and of course, reach out to me using any form of social media (@marvinjoles).
Stay In The Mix. -Marvin
Marvin Joles is the owner of Wis-Coat Asphalt Maintenance. Visit his website at https://marvinjoles.com
