To Seal or not to Seal?

To Seal or Not to Sealcoat your Parking Lot

“Does seal coating really protect my asphalt parking lot surface?” Good question! It’s one we hear A LOT (no pun intended) and by the end of this article we hope to answer that for you. But first, we need to consider a few things. There are three key factors that will let us know us if your parking lot is eligible for a seal coating application or not: Condition, Age & Cost/Benefit.

Three Key Factors of parking lot sealcoating:


Bitumen is the binder which holds the asphalt in your surface together. Over time, the bitumen in the asphalt will begin to break down and the asphalt itself will begin to ravel (come apart). The length of time it takes to break down depends on several factors including amount of traffic flow, age, asphalt mixture ratios and exposure to harsh environments. When evaluating a parking lot for seal coating we must first identify the parking lot as one that is fairly early in its life cycle, free of major cracks & repairs, and still has a strong bond between the bitumen binder & the asphalt stone.


If the parking lot is more than 10 years old and has never been seal coated, than likely, the bitumen on the surface has broken down significantly and the asphalt has begun to unravel. If the parking lot is 10 years old or more, the seal coat will have very little effect on protecting the asphalt.

The older the asphalt surface, the more often the surface must be seal coated in order to maintain the beautiful jet black look that every parking lot owner desires. Over the years, layer after layer of dirt, oil, antifreeze and debris have settle into the cracks and crevices of your asphalt surface. This makes it very difficult for the sealant to bond. After a few years of heavy traffic, the beautiful black will have returned to its original color. Or even worse, it only shows thru in some areas giving an undesirable contrast from gray to black. This tells us that in order to reap the benefits of seal coating, it must be done relatively early on in its life cycle.


Property managers and business owners are always looking for ways to make their properties or storefront look more aesthetically pleasing – but at what cost? Seal coating for cosmetic updates should never take the place or structural and safety concerns. If the asphalt is breaking down badly and the surface is nearing the end of its life, perhaps rolling those funds into major repairs in the future would be more economical. However, if the parking lot is fairly new, seal coating along with crack filling can be an excellent way to improve the look of your parking lot.


In conclusion, it is important to understand that seal coating will not restore or repair an asphalt parking lot. It will, however, make your property look more aesthetically pleasing for your customers and patrons. For more about seal coating and crack fill, see the Ultimate Parking Lot Maintenance Plan.

Need an asphalt paving contractor in the greater Baltimore/DC area? Call us now for a free evaluation of your asphalt paving surface! 410-477-4406

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