A full depth repair is necessary when a failed area cannot be fixed with general maintenance options (such as infrared patching). A full depth repair requires removing all asphalt in failed areas down to the sub-base. If the sub-base is soft, the area is undercut until a solid base is formed. Aggregate base course is installed and the asphalt is replaced. We suggest that if 25% or more of your parking area requires full depth repair, you should consider a total replacement. There are many reasons for asphalt to fail at this level and some are unavoidable. However, full depth repairs can be minimized with a general maintenance plan. Annual inspections and periodic patching of your asphalt surface will prevent serious deterioration and the need for full depth repairs.