Evidence based limits in contractual material
Risk management plays a key role in construction, from single family houses to large infrastructure projects, poor risk identification and management leads to budget and schedule overruns and sometimes even complete project failure. One of key risk elements is weather. The on-site weather monitoring systems and integration of weather forecasts into daily operational planning allows project managers to manage the imminent risks caused by adverse weather events as they happen during the construction execution phase. However, the biggest impact on risk reduction is achievable in the earliest stages of project planning. Inclusion of historic weather patterns combined with multi-season satellite images and elevation models already during bid or tender preparation allows to align the scheduling of key construction phases with local climate and environment. Understanding the expected weather conditions at the project location before suggesting schedules in an invitation to tender or sending a bid is the first major step towards reducing the project’s risk exposure.
Understanding the expected weather conditions at the project location before suggesting schedules in an invitation to tender or sending a bid is the first major step towards reducing the project’s risk exposure. Selecting historically drier periods for groundwork and provision of suitable materials and site protections for the windy and/or wet season can prevent significant losses. Scheduling lifting and work at heights for periods with lower wind speeds and less prone to wind gusts can reduce the probability of costly accidents. An accident on-site can lead not only to loss of key workers, machinery, and materials but also to long interruption until official investigations are concluded.
Evidence based limits in contractual material
Further to the alignment of work scheduling with local weather patterns, it is crucial to define in all contractual material what is regarded as usual and acceptable weather conditions for different seasons.
Most importantly, to include the definition of unseasonal and severe weather conditions and how they affect the bid price, for example by including the weather losses due to regular weather pattern but excluding those caused by outliers.
Using clear, evidence-based definitions prevents long and costly litigations later. Statistical distributions of weather factors can form a basis, as shown in the example below, to set meaningful condition limits (e.g., 3rd quartile or historical maximum).For large projects, where pre-assembly or storage might be off-site, those locations should undergo similar scrutiny before schedules are fixed contractually.
