To make your air conditioning system the best it can be, you must have the best ducting. In the height of summer, the space in your roof can be up to 65oC. Only Ductair's Energy Smart ducting has over 60% higher thermal rating than the Australian Building code Standards Rt1.0 (check the standard for your area). Make your system more efficient and reduce your energy bills. It doesn't cost the earth to be Energy Smart. Always demand Ductair.