In Queensland’s preparations for the intense tropical cyclone Ita, Queensland Prime Minister Campbell Newman suggested that residents living in older homes (houses built before 1985) evacuate homes because they are less likely to withstand The destructive wind of the storm. As a result, damage is primarily a damage to the grid, and Cooktown, which is very close to the storm path, suffers less damage than people fear. But this episode still raises a question: What is special about 1985?
That year, building regulations changed, requiring new homes in hurricane-prone areas to withstand higher winds. But how are these regulations determined and what do they mean for modern homes? Why do regulators always wait until after the storm to update the regulations?
Update regulations
Building codes are developed by the Australian Building Code Council (ABCB), whose mission is to address “safety and health, comfort and sustainability issues”. Its job is to set minimum standards for the design, construction and performance of buildings to “accept natural disaster events related to extreme weather”. The recommended standards are then adopted by each state and region. After a natural disaster occurs, ABCB checks the nature of the building damage to determine if the regulations provide adequate protection. During Hurricane Tracy in 1974, 70% of Darwin’s homes were severely damaged (90% in some areas), causing 65 deaths and hundreds of millions of dollars in damage. It is clear that existing building standards do not protect the community.
As a result, regulations were amended in the 1980s to improve the construction process of connecting the roof to the rest of the house, making the house more resistant to severe windstorms. An analysis of Hance (1999), Larry (2006) and Yasi (2011) shows that the updated regulations reduce building damage and thus reduce life. For example, during the “Asian” hurricane, 12% of old homes suffered severe roof damage, but only 3% of new homes were damaged. Of course, this does not mean that newer homes are completely impermeable. Analysis of the damage caused by Hurricane Yasi revealed some remaining “weak spots”: tiled roofs, sheds, garage doors and doors and windows. It has been found that more attention needs to be paid to the design, testing, installation, use and maintenance of products, components and fasteners. Since then, revised standards have been developed for roof tiles, garage doors and shed designs.
The right way to think about risk
Campbell Newman’s comments on old homes are partly correct, as houses built to old standards are indeed more likely to be damaged. But his statement may also be misleading. The current building standards in the Far North region of Queensland are designed to protect the structural integrity of Category 4 hurricanes. If Ita crosses the coast and maintains its Category 5 strength, all of Cooktown’s homes (new and old) can be severely damaged. It is vital that the community understands which hazards and risks are being addressed by building codes and which are not. For example, current regulations address wind loads associated with cyclones, but wind and rain (the main cause of water damage) is not considered. There are also three unresolved specific hazards: hail, storm surges and heat waves. The first two have property risks; the third is to cause heat stress, which in turn is related to health problems and death.
ABCB considers both costs and benefits when deciding whether and how to update regulations. The regulations will only change if ABCB and its stakeholders determine that the cost of change (such as higher construction costs) is less than the benefit (reducing the expected savings from damage). As a result, regulations establish minimum standards rather than best practice standards.
The role of the community
Therefore, homeowners and residents need to be aware of these limitations in building codes and be more proactive in determining the level of risk appropriate for their situation. A simple risk assessment can identify three things: What hazards and risks might your house/unit/building face? What is the probability and frequency of these hazards? What happens if the incident occurs? Property damage can be the first concern for people, especially those associated with natural disasters such as cyclones, floods and forest fires. However, heavy rain, hail, tidal surges, ground movements and other phenomena can also damage buildings and their contents. Failure to act can also lead to financial risks, such as rising electricity prices and rising premiums. These financial risks affect everyone in the community.
At the same time, people directly affected by property damage may also suffer from resettlement costs and loss of income.
What should you do?
It is important to listen to the authorities, but you should also be responsible for your own family risks. One way is to buy home insurance, but you need to understand the risks and risks of insurance and your responsibilities. Another way to manage risk is to consider these factors when building, buying, or renting a property. Learn how to design and build buildings to manage these risks. Ask the architect, designer, builder, real estate agent, landlord, legal body or local council for documentary evidence.
The insurance industry can also play a more active role in promoting better architectural design, perhaps by offering lower premiums for buildings that are more robust. There is also a need to consider ways to assess and repair damaged buildings after a disaster. New Zealand has acknowledged that the earthquake recovery process provides an opportunity to build a more resilient city, not just to recover lost things.
A more collaborative approach is needed to withstand the risks to our buildings, property and even health. ABCB seems to be moving in this direction and should not be expected to do it alone. Each of us can play a role in creating a strong and resilient community that can withstand natural disasters.
Https://theconversation.com/how-building-codes-save-homes-from-cyclones-and-how-they-dont-25550