What Is Mill And Overlay?

Mill and overlay is a process used in road construction and maintenance to rehabilitate
an existing asphalt pavement surface by removing the top layer of asphalt (known as
the “mill”) and then replacing it with a new layer of asphalt (known as the “overlay”).
The milling process involves the use of a large machine that grinds off the existing
surface layer of the pavement to a specified depth, typically between 1 and 4 inches.
The milling machine removes the old asphalt and any damaged or deteriorated sections
of the underlying pavement.

After the milling is completed, the surface is cleaned and inspected for any additional repairs that may be necessary. Once the surface is deemed ready, a new layer of asphalt is applied, which typically ranges in thickness from 1.5 to 2 inches. The new layer of asphalt is then compacted using heavy equipment to create a smooth, even surface.

Mill and overlay is a cost-effective method for extending the life of an existing asphalt pavement surface, particularly when the underlying pavement is still in good condition but the surface layer has become worn, cracked, or damaged. It can also be used to correct surface irregularities or improve the skid resistance of the pavement.