You may have an asphalt parking lot or road that is starting to look a little old and worn down. So, what’s the plan of action? Should you pave on top of the existing asphalt or completely remove and replace it?
The Difference Between Asphalt Overlay and Asphalt Replacement
Asphalt Overlay
An asphalt driveway, parking lot, or road can benefit from an overlay or resurfacing. It entails laying a new layer of asphalt on top of the existing asphalt and grinding at the transitions (i.e. sidewalks, garages, drains, curbs, or other asphalt points). An asphalt overlay is the correct option for a degraded pavement surface that nevertheless maintains structural integrity.
The best base for new asphalt is an existing asphalt surface. Before installing asphalt, damaged or troublesome sections are rectified. Sometimes all that is needed is a leveling course, which is a thin layer of asphalt that is laid before the finishing course to fill in any dips or low places. A tack coat is usually sprayed to the existing asphalt surface to assist the fresh asphalt to adhere to it. Depending on the project, an overlay is often put at a depth of 1.5″ to 2″ inches thick. Overlays are typically less expensive while providing the same quality and strength as other asphalt choices.
Asphalt Removal and Replacement
The current asphalt is excavated or removed, revealing the gravel base, in the removal and replace project. If any portions of the sub-foundation are soft, they will need to be undercut and fine graded to the required grade. An undercut is a section that must be completely excavated and backfilled with aggregate. Undercuts typically vary in depth but are about 8″ inches deep. After removing the current asphalt and properly repairing the sub-base, a new layer of asphalt is poured and compacted to the proper thickness.
Removal and replacement are more expensive and should be considered only if the existing drive is compromised by the structural integrity of the sub-base, if there is a drainage issue that needs to be addressed, or if there are elevation difficulties. A remove-and-replace service might be an excellent long-term option for your asphalt demands.
Every driveway is unique, and considerations such as neighboring elevations, drainage, and paved surface use can all help to identify the best course of action. Please contact us to schedule a consultation with one of our asphalt experts to identify the best solution for your project.