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Is it acceptable to use a 10 mm cgsc as a flexible footway binder course?
It is not acceptable to use a 10 mm binder course in flexible footways. The standard construction for these layers is 20 mm cgbc for the binder course and 6 mm cgsc for the surface course. In small openings (less than 2 metre square) a single material of 6 mm cgsc can be used for the binder and surface course. The use of 6 mm material as a binder course in small openings is a concession to facilitate the use of a single material.