Our own product – Lightspan . An aluminium stick curtain walling system with a 50mm face width. Available in a wide range of polyester powder coat RAL colours. When tested to CWCT test method 5, Lightspan passed Water Penetration of 1000PA. Air Permeability – When tested to CWCT test method 4, Lightspan passed Air Infiltration of 600PA Thermal Efficiency – Lightspan takes the aesthetic and structural benefits of aluminium and combines them with the thermal efficiency of PVC and TPE.