An asphalt overlay is used to rebuild and repair the entire surface of a driveway where the asphalt has begun to crack or break. It will completely smooth out and resurface the driveway. Asphalt sealcoating is applied to the surface of existing asphalt to improve the appearance and extend the life of the driveway. Sealcoating makes asphalt look better and protects it from the elements. It is not a "repair" solution.