Managing Weather Risks and Impacts in the Australian Construction Sector
Snapshot
- Weather-related disruptions are a growing financial risk for Australian construction projects, which can result in downtime costs of hundreds of thousands of dollars.
- Traditional contract works insurance terms typically do not cover non-damage weather delays, which may leave projects exposed to Liquidated Damages.
- Used together, risk engineering, contract works cover and parametric insurance can help support better outcomes for project owners and contractors.
Aon’s 2026 Climate and Catastrophe Insight Report confirms that extreme weather events are becoming more concentrated in their impact, even in years where overall activity is below average. When Ex-Cyclone Alfred made landfall in Queensland early in 2025, it became the sixth-costliest tropical cyclone on record in Oceania, causing an estimated AUD$2 billion economic losses. In November, a severe hailstorm hit Brisbane generating an estimated AUD $2.42 billion in insured losses. Both events occurred during a relatively calm year for weather-related disruption in Australia.
The report also shares modelling that suggests more intense tropical cyclones may affect the country in the coming decades. With the potential rise in wind speeds and rainfall expected from these events, weather patterns that already disrupt construction sites may continue and potentially increase in duration and impact.
Contingencies for Weather Often Fall Short
Most construction projects rely on predetermined contingency days (float) to account for downtime on site caused by extreme weather conditions. These buffers are typically built into scheduling and pricing, based on the assumption that actual weather disruption will stay within this range, enabling the project to reach practical completion on time and within budget. When contingency is used up, the financial consequences can escalate quickly, with liquidated damages (LDs) potentially accruing daily when sites cannot operate.
“In the past, contractors often worked with relatively conservative float allowances in their project schedules,” says Fabio Lucano, Client Executive at Aon Australia. “Today, with the impact of more frequent and prolonged weather events, we are seeing many project teams increase their contingency periods to better absorb delays and protect their financial position.”
Conditions that can erode a float allowance are varied and triggered by all types of extreme weather. “For high-rise construction in cities, wind can prevent tower cranes from operating safely and under union agreements, sites must shut down when temperatures exceed 35 degrees or 29 degrees when the combined heat and humidity exceed roughly 70%,” says Clint Darling, Client Director for Aon Risk Solutions, Australia. “Heavy rain can also delay work at the site, preventing works or cutting off supply of materials and labour. A chain of these weather events and site disruptions can quickly erode any allowance for downtime.”
“When you start to quantify what these costs are, you realise it could be half a million dollars a day to have your site just sitting there, unable to operate.”
– Clint Darling, Client Director, Aon Risk Solutions, Australia
Exploring New Solutions for Weather Risk Transfer
The extent of this impact on construction schedules and financial outcomes reveals a potential critical gap in traditional contract works insurance. With terms typically designed to respond to damage rather than delays, these programs can leave projects exposed to the financial cost of weather-related delays where no physical damage has occurred. For example, rainfall that halts construction work for days but causes no structural damage can result in no insurable claim and still cost the project hundreds of thousands, or even millions of dollars.
Risk engineering and more targeted insurance structures may help address this. “Doing all you possibly can to protect your site during storms includes understanding which areas will be most affected by rainfall and flooding,” says Lucano. “This type of risk hygiene matters both in its own right and because it influences terms insurers will offer.”
“Because it’s getting harder to predict the weather, we have to make sure we’re on top of all our avenues of risk. We can’t just focus on one area of risk transfer.”
– Fabio Lucano, Client Executive, Aon Australia
Putting Data to Work to Secure Better Terms
When a contractor was commissioned to work on student accommodation in a mapped floodplain, the flood sub-limits applied to their contract works policy left the project exposed to major financial risks from a heavy rainfall event. Aon commissioned a detailed hydrology and flood mitigation study to assess how a major upstream flood event would impact the site. The report included how much warning time the project team would have, and the mitigation measures they could follow based on these estimates.
This evidence enabled Aon to challenge underwriter assumptions with site-specific data for flood risk. Using the modelling and report enabled the contractor to secure full contract works flood coverage, with a suitable deductible, and brief the site team on flood response procedures to limit potential damage and project delays.
Parametric Insurance Provides Extra Protection for Weather-Driven Delays
To help mitigate financial risks from weather-driven site disruption and project delays, parametric insurance can provide cover even when no physical damage occurs. Instead of being triggered by physical damage to assets, a parametric policy links payment to a specific, measurable index—such as rainfall, temperature, wind speed etc., exceeding a predefined threshold. Once that threshold is reached, the policy is designed to pay out automatically. Because there is generally no need to assess physical damage, claims can typically be settled more quickly, giving contractors faster access to funds.
Parametric solutions can be structured to match contract terms and may activate when the project float has been reached. Historical weather data and project-specific modelling can help insurers evaluate the probability of future conditions leading to site shutdown. Using these inputs, contractor and insurer can work together to determine the thresholds and pricing that may suit the site’s potential exposure to extreme weather and the contract terms for the project.
Mitigating Impacts of Heat and Wind on High Rise Projects
Due to wind in central business district locations, high-rise construction projects can often be forced to suspend operations when strong gusts put tower cranes at risk. An Aon client constructing a high-rise building was experiencing repeated shutdowns due to excessive wind and heat and was facing the prospect of substantial liquidated damages (LD) penalties.
To develop a proposal for parametric cover as part of their insurance program, Aon analysed historical weather data for the site location to put forward appropriate heat/humidity and wind-speed triggers for parametric cover. Their analysis included modelling likely shut-down days across the remaining program and matching the solution to the project’s LD liability.
Using an Integrated Risk Strategy to Manage Uncertainty
Effectively managing the impact of a changing climate and extreme weather on construction projects generally requires a multi-faceted approach. Risk strategies may benefit from solutions that can go beyond the limitations of traditional contract works cover, assess weather exposure at the specific project location and apply risk engineering to help improve both site resilience and insurer confidence. This approach can help contractors and project owners to structure their risk transfer to better match their real risk profile.
Aon is investing in data, technology and next generation forecasting models designed to deliver insights and help the construction sector better address the risks of extreme weather events.
Contact us to find out more about our risk consulting, insurance and analytics solutions designed for the industry.
