A good average is 20 years. Architects generally design parking lots to last 20-25 years. Unfortunately, designs on paper and actual conditions in the field can vary quite significantly, and since the parking lot tends to be the last item of construction project, and is obviously less structurally important than the building itself, corners can be cut leading to significant decreases in the parking lots useful life.
Parking lots and driveways that were constructed in the 70′s seem to have held up better over the years than ones constructed in recent years. For structurally sound pavements that are experiencing isolated failures, a maintenance program of patching, sealcoating and striping will prolong the life of the pavement almost indefinitely.
A site inspection is required to assess the remaining useful life of any particular parking lot. C & R Asphalt, LLC.s pavement evaluation study can predict with accuracy how much useful life is left in a particular parking lot. And more importantly what needs to be done to achieve that life.