Whitetopping is the covering of an existing asphalt pavement with a layer of Portland cement concrete.
Ultrathin whitetopping is suitable for light duty uses, such as roads with low traffic volume, parking lots and small airports.
Deterioration of overlays is significantly increased on asphalt bases with high viscosity.
However, whitetopping requires the asphalt layer to be at least 7.5cm (3") thick.
If necessary, a section of new concrete roadway can be placed under a bridge with gentle slopes on either side that meet up with the whitetopped portions of the road.