Failure of Sheet-metal Roofing Under Repeated Wind Loading

Following cyclone Tracy which hit Darwin in December 1974, laboratory and field investigations have revealed that repeated wind loading can produce failure of screw-fixed metal roofing systems at loads significantly below those predicted by static load testing. A repeated loading test criterion for roof cladding has now been incorporated in the Darwin Area Building Manual. Repeated load testing has revealed the need to alter some previously used roof fixing details.