Overlay Patch
An overlay patch is appropriate for parking lots and driveways that still have a relatively sound foundation. An overlay patch will have raised seams and are less expensive than saw-cut patches because they require less time and materials and do not require the use of an asphalt saw. The process for installing an overlay patch is as follows:
- Clean blacktop of loose debris.
- Apply tack coat asphalt adhesive which enables proper bonding between new and old asphalt.
- Prefill designated area with asphalt and compact to level area as needed.
- Install asphalt to adequately cover area tapering edges down to meet existing asphalt.
- Compact with roller.
Saw-cut Patch
A saw cut patch requires some foundation / stone work and the use of an asphalt saw. These patches also require more asphalt than an overlay patch, usually 3" - 4" of asphalt. Notice that the edges of the patch are flush with the existing blacktop. The process for installing a saw-cut patch is as follows:
- Saw-cut and remove existing blacktop.
- Re-grade and compact existing stone base or dig-out existing stone base and reinstall crusher run stone.
- Compact stone base.
- Install 2.5" of type 3 dense binder and compact.
- Install 1.5" of type 7F commercial grade asphalt and compact flush with existing blacktop.