Road Base is one of the most versatile filling products we have. It is basically a crushed blue/grey rock around 20mm in size with smaller sized rock particles right down to “fines” mixed in. This blend of sizes enables the product to be compacted down hard. So for a boggy driveway that needs stabilizing or for preparing a hard surface to lay your pavers on, this is the ideal product.
As well as its compactibility, a measure of a Road Base quality is its CBR rating. This stands for the “California Bearing Ratio” and refers to the actual strength of the rock itself. For any area that requires a hard surface, it is important that the rock used does not disintegrate under load (e.g. a car) so we make sure that we supply a roadbase with a CBR of 45 or higher and one that is used extensively by road builders around Brisbane.
Two final notes about the use of roadbase: Firstly, when it is compacted it will reduce in volume, for example, if you compact a 100mm layer it will reduce to between 75-80mm; secondly, to get the best compaction possible, make sure that the material is wet, as this helps all the “fines” bind tightly with the larger stones.