Cyclone Testing Station releases recommendations following Cyclone Debbie

The team’s investigation included the performance of houses as well as larger residential structures such as apartments and resort accommodation in the communities of Bowen, Proserpine, Airlie Beach, Hamilton Island, Dingo Beach, Wilson’s Beach and Conway Beach.

Cyclone Testing Station director Dr David Henderson said that based on their findings, there are a number of recommendations which could improve the way buildings stand up to cyclones in the future.

“Structural elements in buildings should be inspected every seven to ten years to ensure the integrity of the building,” he said. “It’s important to prevent one failed element of a structure from setting off a chain reaction of failures across the building. Where one part of the roof requires maintenance, the remainder of the roof and related structures should also be checked and upgraded at the same time.”

Another recommendation is for the development of guidelines for ‘safe compartments’ within residential buildings. These would offer enhanced protection in the event of wind speeds exceeding the levels the building was designed for, or following damage to parts of the building during the cyclone.

The report also supported previous findings that older houses are more susceptible to severe structural failures. However, damage to interiors from wind driven rain that came through flashings, windows and doors had a significant impact on modern buildings.

“Much of the structural failures were in buildings constructed before the current cyclone building standards were developed in the 1980s, however we also saw failures on some recently constructed buildings,” Dr Henderson said. “The damage ranged from a few instances of major structural failures, such as loss of roofs, through to hundreds of cases of internal damage caused by rain.”

Full report: https://www.jcu.edu.au/__data/assets/pdf_file/0009/461178/TC-Debbie-report.pdf

Key recommendations:

• Adequately detail roof to wall connections;
• Improve fixing of flashings;
• Improve performance of window and door furniture under repeated wind loads;
• Undertake research to determine strategies to reduce the volume of wind-driven rain entering through windows and doors in otherwise undamaged buildings;
• Inspect, maintain and retrofit if necessary structural elements in buildings constructed before the 1980s;
• Check the structural adequacy of roof elements in all buildings after any severe wind event and/or at seven to ten year intervals;
• Develop guidelines on the design of strong ‘safe compartments’ within residential buildings; and
• Revise 2011 storm surge guidelines.