The Cyclone Testing Station (CTS) is the pre-eminent independent authority on the performance of buildings in severe wind events. CTS is located at James Cook University in Townsville and focuses primarily on the performance of houses and other low rise buildings in Australia and the surrounding region. Activities include investigations after wind events as well as research, testing and community education, aimed at ensuring that buildings designed to resist severe wind events are safe, economical and sustainable.
CTS wishes to thank its benefactors and sponsors for their ongoing support of its activities. Click here for a list of CTS Benefactors and Sponsors.
Category 4 Tropical Cyclone Debbie crossed the Queensland coast north east of Airlie Beach around midday on Tuesday 28 March 2017. CTS teams investigated the performance of houses; larger residential structures such as apartments, strata properties and resort accommodation; commercial and public buildings; and sheds. The study area included the communities of Bowen, Proserpine, Airlie Beach, Hamilton Island, Dingo Beach, Wilson’s Beach and Conway Beach. The buildings within the study area were estimated to have experienced wind speeds lower than their relevant design wind speed. However, there were many observations of damage to contemporary construction. For example, damage ranged from a few instances of major structural failures of roof structure, through to damage of many cases of internal linings from wind driven rain water ingress via damaged flashings or water via windows and doors. The report provides recommendations to improve the performance of building structure and cladding systems including: adequate detailing for roof to wall connections; improved fixing of flashings, retrofitting options for older buildings; improvements in windows and door furniture under repeated wind loads; and revision of storm surge guidelines.
To read the full report please click here
Recent CTS damage investigations have highlighted problems with flashing details on buildings, leading to water ingress and often significant internal damage. The house on the left has lost a flashing on the windward wall. The house on the right illustrates the internal damage that can result from a lost flashing.
Roof flashings appear to be a particular problem but issues have also been identified with poor flashing detail around doors and windows.The issues are not isolated to one state or local area, with flashing problems observed after Cyclone Marcia in Queensland and after Cyclone Olwyn in Western Australia.
The Cyclone Testing Station recommends that suppliers of flashing materials and suppliers of materials that require flashing ensure that proposed detailing has been fully documented and properly evaluated and that clear and detailed installation literature is readily available. It is also recommends that any documentation indicates whether the proposed flashing detail is adequate for cyclonic areas.
The Cyclone Testing Station further recommends that designers, specifiers, builders and certifiers pay particular attention to flashing detail, to ensure that what is otherwise quality construction is not compromised by poor flashing detail.