Sarking

Sarking (also known as roof underlay or building blanket) is a critical component in modern Australian roof construction. It serves multiple functions: it acts as a secondary waterproof barrier if wind-driven rain penetrates past the roof covering, it reflects radiant heat to improve thermal insulation, and it prevents dust and airborne embers from entering the roof space. In bushfire-prone areas, sarking is a mandatory requirement under the Australian Standard AS 3959 for construction in bushfire-prone areas. Modern sarking products are typically a multi-layer laminate consisting of a woven polyethylene fabric with a reflective foil face, a polyethylene vapour barrier, and sometimes an absorbent anti-condensation layer. Common brands in Australia include Bradford Anticon, Sisalation, and Enviroseal. The sarking is draped over the rafters or top chords of the trusses before the battens and roof covering are installed, with overlaps taped or sealed to form a continuous barrier. In Gippsland, sarking is particularly important due to the region's high rainfall and the prevalence of condensation-prone roof spaces during cold winters. Without sarking, condensation can form on the underside of metal roofing and drip onto ceiling insulation, reducing its effectiveness and potentially causing water staining on ceilings. When Town & Country Roofing undertakes a complete roof replacement, sarking installation is a standard inclusion.