What is the best way to create a construction project schedule that accounts for weather delays?

Go into the project with the understanding that weekdays, hours lost can be recovered by working weekends. Deadlines are deadlines. A deeper dive might suggest that weather days are excuses for not completing the work on schedule, which leads to all kinds of other questions-were staffing levels appropriate? If we are pressed to do so, we usually use 4 days a month in the upper Midwest if geography plays a role-otherwise, properly staff for the project duration.

Then place the average of 5 years non working days on the calendar that affects external trades. Don't forget that it rains on weekends and holidays. It's not just rain, high winds, frost, snow and extreme heat also affect the weather. When you do a progress report take out the anticipated days and add the actual days and adjust the terminal float duration accordingly.

Start by researching historical weather patterns for the project location. Incorporate buffer days into critical construction phases to allow for unforeseen weather disruptions. Prioritize flexible scheduling, ensuring that weather-sensitive activities are strategically placed in the project timeline. Regularly monitor weather forecasts and adjust the schedule proactively. Utilize construction management software to facilitate real-time updates and collaboration. By combining historical data, flexibility in scheduling, and advanced monitoring tools, project managers can develop resilient construction schedules that mitigate the impact of weather delays on overall project timelines.

To create a weather-proof construction project schedule, you should research the historical and seasonal weather patterns of your project location, as well as the expected weather conditions during the duration of your project. This will help you estimate the number of workdays that might be lost or delayed due to adverse weather, and plan accordingly. It is advisable to consult with local experts, such as meteorologists, contractors, or suppliers, to get a better sense of the typical weather challenges and opportunities in your area.

Developing a construction project schedule that accommodates weather delays requires strategic planning. Start by researching local climate patterns and integrating buffer time into the timeline. Utilize advanced weather forecasting tools for real-time monitoring and prioritize weather-sensitive tasks. Establish clear communication channels, consider modular construction methods, and invest in weather-resistant materials. Regularly review and update the schedule to adapt to changing weather conditions. This proactive approach ensures project resilience and successful completion despite unpredictable weather challenges.

Using a buffers on tasks or phases could be considered sequestration of float. A project really does not need a "day" of weather extension unless the weather event actually impacted an activity on the current critical path. The best method for inserting a "buffer" for normal, anticipated weather is as a weather allowance activity on the planned critical path, right before substantial completion. The allowance is reduced by each day the critical path is impacted by a weather event.

Workers should not try to take advantage of buffers which are added to individual tasks solely for the purpose of dealing with weather delays. The schedule must be revised quite often because weather is unpredictable. Otherwise, a fixed schedule with buffers in task durations gives an overestimate of project duration. It is better to create an appropriate buffer at the end of the project rather than create it in task durations, if possible

Many schedules I work with have a contingency buffer for both adverse weather that precludes any work and for cold or hot weather that impacts production. The contingency is drawn down as the impacts are realized. The contingency allows for flexibility of when to utilize the contingencies. For example, if concrete pours were delayed from fall to winter, additional contingencies for winter-work would be expected. If winter work was done sooner - in the fall - the expected contingencies could be reassigned.

Weather delays depends on the type and complexity of your project, as well as the level of risk and uncertainty you are willing to accept and also depends on what are the available contractual provisions can take into account for contingency buffer.

Some of the newer schedule risk software, like Safran Risk, have capability to create a probabilistic weather calendar based on historical weather data. This looks like a better method Than fixed weather window calendar. Then use the calendar to determine weather buffers.

Layer probabilistic calendars that model weather risk onto deterministic CPM schedules to create scenarios of weather impacted schedules.

CPM helps prioritize the most important activities, allocate resources, and avoid bottlenecks. Flexible scheduling methods (Float, or slack, refers to the amount of flexibility of a given task) can help you cope with uncertainties, risks, and delays that may affect your project.

On site weather monitoring stations are a great investment and provide a valuable source of weather records. But schedule progress should be updated manually because the weather station cannot tell you the effect of weather events.

Be clear in the contract if weather days are included or excluded to avoid a conflict in the future. The contractor must keep track of the weather days and communicate clearly when they are faced with a delay. Consider other work that can take place during rain, snow, or a storm, such as interior work to avoid a delay for all trades. Weather delays should only affect the project schedule if the task affected is on the critical path, this is important to understand on the owner side.

I usually maintain two sets of calendars, wet calendars with an allowance for weather for long term schedule forecasts, and dry calendars for near term look-aheads. This allows you to switch between the two (global change in P6 is your friend here) and recalculate the schedule.

Know your location, Weather and Contract. Notice regimes and contractual provisions can help make your project weather proof such as Force majeure clauses (especially for weather factor), Extension of time clauses regards to adverse weather implications and Weather measurement clauses (Define weather adversary) suggested to be used to future dispute avoidance.

What I think the best way to do that is learning from the past experiences. You can withdraw all the data of past weather and do some analysis for that specific data and conclude results from that data. You can also mine in past development projects in that specific area to access the results of weather for that project and fit it into your plan accordingly. I think this most suitable approach to do it as human intelligence.

1.Contractual Agreements: Clearly outline weather-related clauses in contractual agreements with subcontractors. Define the procedures and responsibilities in case of weather delays, including the extension of timelines and associated costs. se Construction Management Software: Utilize construction management software like Primavera or MS project that allows for real-time updates and adjustments to the project schedule. This enables quick responses to weather-related challenges and helps keep all stakeholders informed.