Common Construction Scheduling Mistakes that Should be Avoided

Introduction:

The project construction schedule is a key element for the success of a project. A good construction scheduling covers all the aspects as per guidelines of project management knowledge areas. Therefore, it would consider every aspect of the project which is deemed to be necessary to achieve project completion in a timely manner, within the budget, and as per the scope of work. Learn more about the golden triangle ( cost, time, and quality).

What is known to be a good construction project schedule?

Attributes of a good construction schedule are listed below but are not limited to:

• It should reflect the contractual scope of work.
• All the relationships in the schedule are reasonable and well-defined.
• The critical path should be logical.
• It should cover project resources availability and their utilization on the project.
• The duration of activities should also be logical and take into account the magnitude of work and resource availability.
• Milestone dates should also be as per contractual requirements.
• All the cost and resources data should be loaded into the schedule
• Risks may also be included in a good schedule.

The above-mentioned attributes of a good construction project schedule require a lot of attention and skills from a project scheduler and project manager. Any discrepancy notwithstanding these requirements may lead to the failure of the project in terms of cost, time, quality, and reputation of a company.

Common construction project scheduling mistakes and their solutions:

For a project manager or project scheduler, a construction schedule requires good command over scheduling software and in scheduling techniques. If a project manager or scheduler has basic knowledge of scheduling software, it may work, but little knowledge about scheduling techniques may not work.
Below are some of the mistakes that should be avoided while preparing and updating a construction project schedule, along with their optimal solution.

Not considering the project scope of work:

The project scope of works should be considered as per contractual documents and any failure to comply with the scope of works schedule may lead overall schedule as incorrect.
So, before preparing any project schedule, the contractual scope of work should be considered as a must requirement.

Lack of knowledge about scheduling techniques:

A lack of knowledge about scheduling techniques, such as CPM (Critical Path Method), resource leveling, PERT, etc will also result in an illogical schedule because the schedule may not make any sense.
So, the project manager and schedule should have in-depth knowledge about these scheduling techniques.

The project is not set up properly:

If the project is not set up properly in terms of the working calendar, currency, and measuring units in any scheduling software (Primavera, MS Project), it will also result in a poor schedule.
So, it should be ensured that the project settings are correctly configured and that the calendar, currency, and measurement units are all set up correctly.

Not defining the WBS:

This may result in a big mistake if we fail to define the Work Breakdown Structure (WBS) for the project.
So, we have to create a detailed WBS to define all project tasks and subtasks.

Not considering all project tasks and subtasks:

Most of the schedulers often miss some of the activities in a project because they are mostly copying some other project’s schedule but this schedule has some additional activities which were specific to this project. This would not let the schedule be approved by all stakeholders.
Ensure that all project activities are included in the schedule, including procurement, commissioning, and testing.

Not defining or ignoring activity relationships and dependencies:

If the activity relationships are ignored or not defined properly, it would disturb the overall schedule. Even the critical path would also not make any sense in this case. Also, if there are more than two open-end activities, then the schedule would not reflect actual dates.
So, it is advised to define activity relationships using the network diagram to ensure that all dependencies are correctly modeled.

Wrong estimation of productivity rates:

This is the most common mistake even by senior schedulers and project managers as they wrongly estimate the productivity rates. Some schedulers are taking data from previous similar projects and using it in a new schedule but this does not work in every schedule.
So it is recommended to avoid this mistake by using realistic productivity rates for each task, based on a bottom-up estimate or the organization’s standard productivity rates.

Underestimating the impact of change orders:

Change orders and reworks mostly affect project schedules because these are unforeseen at the start of the project. It is not easy to consider them in the baseline schedule, but their potential impact can be incorporated into the original schedule.
Hence it is better if we anticipate potential changes to the project scope and schedule for change orders in the original schedule.

Not incorporating constraints appropriately:

Constraints in the schedule should be used properly and auto selection of constraints may affect some of the activities in the schedule.
Hence, the constraints should be used only when necessary and with caution, to ensure that the schedule remains flexible.

Not considering resources availability schedule:

Mostly, inadequate planning for resource availability results in poor schedules in terms of execution. Because some of the resources are assigned to specific activities but their availability is not matching with the resource calendar will result in an inconsistent schedule.
So it is recommended to ensure that resources are allocated based on their availability, and that resource usage is tracked in the schedule.

Over-allocation of resources:

A schedule would not provide the correct value of cost and other parameters if the resources are over-allocated. Also, the monitoring and controlling part will be not implemented properly if the resources are over-allocated.
Therefore, it is better to avoid the over-allocation of resources by using the resource leveling function to balance the workload across the project.

Not assigning baseline to schedule:

If the baseline is not maintained and assigned to a schedule, then we will not be able to update the project progress.
So, it is always recommended to establish a baseline to track progress against the original project plan and use it to identify and address any deviations.

Not considering alternative scenarios:

A one-dimensional schedule or a schedule created with only one plan in mind mostly faces issues during the execution phases. A good schedule should have flexibility, alternative options, and the ability to accept changes.
Hence, it is always better to create multiple versions of the schedule to explore alternative scenarios and identify the most efficient schedule.

Poor coordination and communication with project stakeholders:

Every stakeholder of the project should be taken into confidence while preparing a schedule. The site team, estimation team, project managers, and even sponsors should be in the loop and good communication should be established while preparing a project schedule.
Therefore, a good practice is to establish clear lines of communication with stakeholders, including project managers, contractors, and subcontractors.

Underestimating the importance of risk management:

Construction schedules should include risk management strategies to mitigate potential risks, such as weather, pandemic, earthquake, and other unforeseen situations.

Lack of training and skill level of scheduler/project manager:

A lot of expertise is required to prepare a good construction project schedule. If the project manager or scheduler does not have the required skill level, use of scheduling software, scheduling techniques, and knowledge of contractual obligations, definitely the schedule will not be appropriate.
It is always recommended to have proper training of project managers and schedulers to ensure the growth of knowledge and skill level.

Conclusion:

Preparing a construction project schedule is a critical task that requires careful planning and attention to detail. A well-crafted schedule can ensure that the project is completed on time, within budget, and to the required quality standards.
However, there are several common mistakes that schedulers and project managers should avoid when developing a project schedule. These include inadequate planning, inaccurate estimations, lack of contingency planning, poor communication, and failure to monitor progress regularly. By avoiding these mistakes, project managers can increase their chances of success and deliver projects that meet stakeholders’ expectations. It is, therefore, essential to invest time and effort in creating a robust project schedule that takes into account all factors that could impact the project’s progress.