Asphalt Maintenance

Asphalt patching, hot mix and cold mix

Fixing potholes in your parking lot quickly is important for several reasons:

•    Reducing the risk of lawsuits: Potholes are one of the biggest sources of lawsuits because they pose trip
hazards and can cause vehicle damage.

•    Preventing bigger problems later on: Potholes allow water to penetrate your parking lot. Water that sits on asphalt and seeps into the cracks will eventually deteriorate the base of your parking lot, requiring much larger and pricier repairs later.

•    Maintaining curb appeal: Potholes make your property look run down and uninviting to customers.

The least expensive and least intrusive option for repairing this type of hazard is to fill the holes using hot mix asphalt, then seal the edges to prevent water penetration. Hot mix asphalt patch represents a temporary fix; its lifetime will depend on traffic and use. Hot mix asphalt patch is best thought of as a “band-aid” until a more permanent fix can be performed.

During the winter months, when hot mix is not available, ACMC offers a cold mix alternative that can be used in any temperature as a temporary fix for potholes. Although cold mix patching will not last very long, it can help maintain the asphalt surface until spring, when a higher quality repair can be made.

Patching and Repair

Failed areas of a parking lot need to be repaired to prevent further deterioration and base erosion. This will help to extend the life of the parking lot, postponing the need for complete removals. Several options are available to repair failed areas, including full depth repair, partial depth repair, and surface patching. Our experienced estimators can assess the current state of your parking lot and draft a long-term maintenance plan that meets your budget.

Surface Patching

Surface patching involves installing 1–2 inches of asphalt in designated failing areas of the parking lot. It is similar to resurfacing but on a smaller scale. The asphalt is installed with an asphalt paver and compacted much like the installation of the original parking lot. This option is often suggested for areas that are cracking but not crumbling.
Although a surface patch will help prevent water from further penetrating the asphalt, it is still a temporary fix, with an estimated lifetime of approximately two years, depending on traffic and use of the area. The edges of the patch are tapered to the original asphalt and are subject to abuse by snowplows and general traffic. To eliminate the risks associated with raised pavement, a partial depth repair is often recommended.

Partial depth repair

A partial depth repair involves grinding off the top 2–3 inches of asphalt, replacing it with new compacted asphalt, and sealing the edges. Although a partial depth repair is more costly than surface patching, it is a considerably less expensive option than a full depth repair and can be performed in about half the time. Partial depth repair is only feasible when the deterioration occurs only in the surface layer of asphalt. It is not suggested when problems are caused by a sub-base failure. One benefit of performing a partial depth repair rather than patching is that the edges and grade match the surrounding asphalt, which eliminates problems with raveling edges.

Full depth repair

A full depth repair is necessary when the failed area can’t be fixed with any general maintenance techniques. A full depth repair requires removing all asphalt in the failing areas all the way to the sub-base. If the sub-base is found to be soft, the area will be undercut until a solid base is found. Aggregate is then installed and the asphalt replaced. Some studies suggest that if 25% or more of your parking area requires full depth repair, you should consider a total replacement. Although there are many reasons for asphalt to fail to this level, some of which can’t be avoided, full depth repairs can be minimized if you have a general maintenance plan for your parking lot. Annual inspections and periodic patching of your asphalt surface can help prevent serious deterioration and the need for full depth repairs.