Base course under bitumen, asphalt and pavers: Use Class 1 material. Provide a minimum 100 mm thick course for local access roads (type A and B pavements) and neighbourhood access roads (type C pavement). Provide a minimum 125 mm thick course for access/ suburban route (type D pavement) and industrial access (type E pavement).
Sub base course: Use Class 2 material (or alternatively Class 1 material) to construct a minimum 100 mm thick top layer. Use Class 3 material (or alternatively Class 2 material) to construct subsequent sub base courses as required to obtain design pavement thickness.
Material maximum size: Do not use class 1 crushed rock exceeding 25 mm nominal size in base courses where surfacing is spray seal or asphalt less than 50 mm thick.
Cement treated materials (where specified): Spread cement and mix in place using approved specialised plant or mix off-site in a suitable batching plant.
Pavement widening or rehabilitation: Select paving materials to match the characteristics of the existing pavement profile. Use low or high permeable material as appropriate to minimise differential permeability.
