Concrete Overlays
The Best Choice for Durable Pavement Overlays
Overlays | Installation Process | Design Factors | Success Story | Ultra-Thin Overlays
A deteriorated asphalt parking lot, full of potholes and puddles, is both an eyesore and a safety hazard to everyone who uses it. Owners can transform a rutted asphalt surface into an attractive, functional parking area by covering it with a concrete overlay, or whitetopping. Standard overlays are 4-6 inches thick, but they can be as thin as 2 inches (for low-volume roads) or as thick as 17-20 inches (for airport runways). One of the advantages of overlays are their simplicity: surface preparation is minimal, and existing concrete paving equipment can be used for placement.
A properly-designed concrete overlay will provide many years of low-maintenance service. Most projects have an expected life cycle of at least 20 years, while some have lasted for as long as 30-40 years. Although concrete has a higher initial cost than asphalt, it lasts much longer and requires less maintenance, resulting in a significantly lower life cycle cost. An alternative to conventional concrete overlays are ultra-thin overlays, a durable, fast, and competitively-priced overlay technology which has generated much interest in recent years.
Design of Concrete Overlays for Asphalt Parking Lots
A Publication by NRMCA and PCA
Also check out the Guide to Concrete Overlay Solutions (PDF),
a 32-page report by the National Concrete Pavement Technology Center.



