Construction scheduling best practices

Why is scheduling important in construction?

Scheduling is crucial to the success of a construction project. The appropriate schedule ensures completion of the work on time and within budget, describing the way in which tasks are performed, the pace of activities performed, as well as the methods and sequences of delivery of materials. Some key points to note that illustrate the importance of the construction schedule:

• Having a construction schedule allows companies to see whether client-defined timelines are achievable or not.
• Scheduling assigns dates to project tasks and activities.
• It allows companies and contractors to estimate preliminary costs.
• The project schedule is used to prepare proposals and proposal estimates.
• Scheduling allows the project manager and director to match equipment, materials, labor and all other resources with tasks and activities over time where resource usage is optimized.
• Scheduling allows the sequencing of tasks that prepare teams for the next activities that need to be performed.
• By sequencing tasks and activities for maximum workplace protection, safety performance is improved.
• Having a construction schedule allows the construction team to set their goals and see the dates needed for them to be accomplished.
• Scheduling reduces downtime and production bottlenecks, thus eliminating delays in the delivery of the entire project, ensuring that the project is completed in the shortest possible time.
• A detailed construction schedule serves as a means to monitor the progress of construction work and to juxtapose actual work with the schedule to determine whether execution is proceeding competently.
• A detailed construction schedule can also be compared with actual construction performance and achievements to distribute responsibility for project delays caused by strikes, change of ownership requests, and other unplanned events.

Since a construction project is fundamentally a multitude of smaller construction tasks, having a well-planned construction schedule can coordinate all of these individual tasks and the people responsible to harmonize all of these dynamic aspects of a construction site.

Guidelines for Developing a Good Project Schedule

There are many simple scheduling practices in construction. But with larger, more complex projects, there is a need for more formal scheduling procedures. Having a detailed, practical, and simple-to-use construction schedule means your suppliers know exactly when and what to deliver, your subcontractors know when to hire their workers and tradespeople, your general contractor and other stakeholders can monitor the project, and the project owner can see the overall construction progress.

A good project schedule is one that is accurate and up-to-date, where communication about the project is prioritized and collaboration is ensured to support the successful completion of a project. A great starting point for formulating a well-thought-out project schedule is to ask the following questions. If your construction schedule can answer these questions, you'll be on your way to organizing your project and tracking its progress.

• What tasks are needed to be performed?
• When do they need to be done and in what order?
• How long is each task?
• What resources are needed for each task?
• Who has the competence to perform each task?
• What dependencies exist between tasks?
• What are the project milestones and what work is needed to be carried out at these points?

When creating a construction project schedule, the following are just some of the common methods used:

1. Excel Spreadsheets. This is one of the simplest ways to stay organized. People working on the project can access the Excel spreadsheet documents and add their comments, attach their photos and add other notes. However, documents often end up as an external link to other means of communication (WhatsApp, email) and may not keep all communication details in one place.
2. Gantt charts. Bar charts are also an easy way to track a construction project. Gantt charts are the easiest bar charts for creating schedules. Gantt charts present a list of activities with all relevant details, including time and duration.
3. Master Build Program. The Master Build Program is the easiest schedule to make using Microsoft Project software. The Microsoft Project construction schedule is considered the best for making a detailed timeline until completion. However, it's not the quickest or easiest thing to create, as it requires an experienced planner to list each individual task and put everything into MS project software.
4. Resource Oriented Scheduling. As the name implies, this technique revolves around project resources. It is generally used in projects with resources that are not readily available. Delays are expected with this construction scheduling method as time is allocated waiting for resources.
5. Balance Line Technique. This type of construction scheduling focuses on repetitive work and distributes resources as needed by individual step of the construction process or operation. This scheduling technique avoids delays between activities and is derived from manufacturing processes.
6. Q Scheduling. Q here can mean quantitative or queue . When used as quantitative, it refers to the quantities in various aspects of the project that make up the entire project schedule. If used as a queue, it refers to sequences of queues and the different segments between activities.
7. Critical Path Method. This widely used scheduling technique calculates the minimum completion time for a project, along with the possible start and end times of project activities. It focuses on the critical path, which represents the set or sequence of activities that will take the longest to complete. Because the critical path duration represents the minimum time required to complete a project, any delays along the path would mean that more time would be required to complete the project.

The Benefits of Data-Driven Project Scheduling

Creating and changing project schedules can sometimes feel like a tiring, rushed, and reactive process. But by using data-driven scheduling, you can predict the construction schedule, empower your teams to have greater input into the overall construction schedule, and be more proactive in making important data-driven construction decisions.

Data-driven project scheduling allows you to take a strategic view in which you use data to proactively resolve any issues before they even arise. A good formal construction schedule will integrate all necessary construction details so that you can see and prevent any problems before they occur or have resolution processes in place.

Another benefit of data-driven project schedules is the ability to create consistent, manageable workloads for on-site workers. Additionally, it empowers your employees to take on more responsibilities and take control of their roles as they can see the overall timeline and consequences if they don't perform their tasks efficiently.

What is a CPM (Critical Path Method) schedule in construction?

As mentioned previously, the critical path method is the most widely used scheduling technique in construction. It has been around since the late 1950s and its use becomes even more popular with each decade, especially on large projects. Many texts and experienced project managers consider critical path scheduling to be the only practical scheduling procedure. Since CPM assumes that a project has been subdivided into construction activities of fixed duration and distinct predecessor relationships, this type of construction scheduling can definitely handle projects with thousands of activities.

Related article: The importance of strategic planning in construction companies and projects

The Program Analysis and Review Technique (PERT) is often used in conjunction with CPM. PERT is a technique used to estimate task duration – if done correctly, these duration calculations are accurate. These duration calculations are defined per task and entered into the Critical Path Model to determine critical paths and tasks. After that, the project manager, planner or director can schedule the construction project.

To generate the Critical Path Model, you need to have the following information on hand:

• The list of construction activities detailed in a work breakdown structure organized by hierarchy or what needs to be completed first.
• The time or duration per activity, which is needed to outline the overall construction schedule – using PERT allows you to obtain accurate estimates.
• The various activity dependencies that must occur before other tasks can be performed.
• Milestones and deliverables, which indicate when a task or activity is completed.

Once you have all the information you need, you can use a Gantt chart to visualize your CPM – this allows you to see an overview of your critical path timeline and the dependencies between all your different activities and scheduling platforms. Typically, this visualized CPM is integrated into the general contractor or project manager's overall delivery schedule to better manage their subcontractors and further improve the delivery schedule.

The main milestones of a project under construction

A construction project, whether a personal renovation or a commercial infrastructure, goes through the same phases. Common milestones for a project under construction include:

1. Project Approval. This milestone is reached when the size, function, objectives and quality of a construction project are determined along with estimated costs and expected financial benefits. The milestone is usually indicated by completing an approval form or a sales contract. This is the first milestone that allows the construction project to move forward.
2. Requirements Review. Once all project requirements have been defined and reviewed through a series of meetings and document review sessions, and the client agrees with what the project team has presented, another project milestone is celebrated.
3. Project approval. Project approval is another crucial milestone when the project team meets the client's needs with its proposed construction and design solution to satisfy the construction project objectives.
4. Execution project. This is the beginning of the physical construction itself.
5. Project phase milestones. These are specific solutions implemented to indicate marked milestones and may include completion of phases such as concreting, plumbing installation, window installation, roofing, etc.
6. Project delivery. This milestone marks the overall completion of a project and occurs at the end of extensive inspections and testing and a final handoff session in which all stakeholders agree that all work has been completed and met all project requirements.