When an asphalt pavement surface deteriorates to the point of needing repair, an asphalt overlay is an effective solution. A standard asphalt overlay consists of a new layer of asphalt applied over the existing asphalt surface. The thickness of an overlay is typically 1 1/2 inches, but both the type and the amount of traffic as well as individual customer’s needs are also considered.
An “overlay” is the paving of a second layer of asphalt over existing asphalt. An overlay can be done when the existing asphalt is in overall good condition but may have some problem areas. Depending on the degree of cracking, crumbling or sunken areas, those areas can be cut out, patched and then a new layer can be paved. An overlay should NEVER be done on a driveway or parking lot that is severely cracked, crumbling, wavy or has sinking, soft spots. The new layer of asphalt will follow the old asphalt cracks (reflective cracking) and waves in a very short period of time. Unfortunately, every year we replace recently overlayed driveways that less reputable contractors have resurfaced. Sadly, once they have cashed your check, they will never return to rectify any problems.
The proper installation of an overlay must include saw cut butt joints. A butt joint keeps all areas level where the new asphalt meets the other surfaces such as garage floors or aprons, sidewalks, curbs and especially the street where no curb is present. Asphalt should never be “tapered down” to meet any other surface because asphalt that is only one-quarter to one inch thick will never hold up against the weight of vehicles or the blades of a snow shovel or snowplow. Many companies do not take this step, which rapidly leads to asphalt failure and the necessity to tear out all of the asphalt and start from scratch. Done properly, an overlay should look like a brand new driveway with all surfaces level and flush at walkways, garage aprons, etc., for a perfect finished look, and provide many years of service.
Prior to paving an overlay, a tac coat primer should be used. This is the glue that is used to adhere the new asphalt layer to the existing asphalt. Again, many contractors skip this step and have less than acceptable results.