As rubber chippings have a different density than gravel, please use the following table to calculate quantities required: 1 bag = 2 approx. 1 bag = 2 approx. 4 bags = 1m 2 approx. 8 bags = 1m 2 approx. 1 Bulk Bag (875kg) = 10m2 approx. 1 Bulk Bag (875kg) will cover approx. 5m 2 approx.