Accommodate Bad Weather in Primavera P6
Unless you are working indoors, the weather is always a consideration when building a construction schedule. Somehow, inclement weather must be addressed for any work which is impacted by it. So what do we do?
Based on historical data and current forecasts, a Project Manager can plan with a degree of uncertainty (as the weather, even with forecasts, is not an exact science) a weather day reserve to mitigate against the detrimental impact of poor weather. The Project Manager will decide how many days to set aside for bad weather and this reserve is typically owned solely by management.
The bad weather reserve acts like a concentrated safety margin at the end of the project and is only used if inclement weather halts the project. If not, then the project will finish earlier than expected.
By adding a reserve of bad weather in Primavera P6, the project manager is offering transparency to the stakeholders by factoring in inclement weather. Let’s take a closer look.
In our construction schedule, the Project Manager has tasked us with adding a rainy day reserve of 3 days. As our project is due to start on April 1st and April is a predominant month for showers, the Project Manager is confident that rainy weather will affect our project and is anticipating 3 days. Therefore, in the example below, we’ll insert a rainy day reserve activity after ‘inspect installed piping’, at the end of the project.
This increases the duration of our project as our schedule was originally due to complete on April 12th. The rainy day reserve is set to delay our project completion until April 17th. However, if there are no rainy days, our project will complete on April 12th as originally planned.
By inserting a reserve of bad weather in Primavera P6, we have created a buffer against project delays in the planning stage of our project. By strategically locating our bad weather reserve at the end of the project, if there aren’t any delays, our project will complete on time.