Replacing a surface
What is the difference between resurfacing and repaving?
Resurfacing puts a new layer of asphalt over the old one and keeps the base, while repaving takes the old surface out and rebuilds what is underneath it.
The numbers
- Resurfacing, also called an overlay: new asphalt over the existing surface.
- Repaving: the old surface comes out, the base is repaired or rebuilt, new asphalt goes down.
- The base decides which one you are buying. The surface does not.
- An overlay raises the finished height, which matters at garage doors, curbs and drains.
What an overlay assumes
An overlay is a new wearing course laid over what is there. It assumes the base under the old surface is sound and the old surface is not moving. Where that is true, it is the better value by a wide margin, because the expensive part of a pavement is the ground under it and you are keeping that.
Failed areas still have to be cut out and rebuilt before the overlay goes on. Asphalt laid over alligator cracking reflects the same cracks through to the new surface, because what was moving underneath did not stop moving.
When the old surface has to come out
Once too much of the base has failed, an overlay is new material sitting on a bad foundation. It gets torn out, the wet or loose base comes out with it, new compacted stone goes in, and new asphalt goes over that. It costs more because it is a bigger job, and what you are buying is a new load-carrying layer rather than a new-looking one.
Height is the other reason. Where the surface cannot go up, at a garage door, against a curb, at a dock or around drainage, the old material has to come out even if the base is fine.
The word in the middle
Mill and overlay is the third option and it is the one most people have not heard of. A machine grinds off the top inch or two of the old surface and new asphalt goes back in its place, so the finished height stays where it was. It is the usual answer on a lot with curbs and catch basins already set to grade.