I think when Austman says the BCA is low, what he means is that the actual noise reduction of insulation that’s installed to minimum BCA standards is inadequate for the realities of modern living. Someday, we can only hope, someone will come up with correlation between the thickness and density of a concrete slab and the type of materials that may be used as floor coverings. Until then it’s quite clear that floors built to minimum standards should never have anything on them except carpet and insulation.