The flow of information on a given project is the responsibility of the Tulsa commercial contractor. Once the project is awarded to contractors and subcontractors the submittals are close to follow. Because the Tulsa commercial contractor is responsible for scheduling and overall procurement and installation of the project the submittals flow from vendors and subcontractors to the prime contractor, then architect and engineer, and then to the owner if needed. The reverse flow of submittals happens once they have been reviewed. Throughout the submittal process the Tulsa commercial contractor is scheduling not only the work but the procurement of material to install. The scheduling and procurement process can be a tedious one. The American Institute for Constructors or AIC gave the following types of scheduling methods:
“… The terms planning and scheduling are often used interchangeably; however, there are important differences. Planning is the all-encompassing approach to completing a project. It addresses the specifics of who, what, where, when, and how a project will be constructed. Scheduling is a subset of planning and specifically addresses the when aspect of planning. There are several tools available to help the construction manager schedule a project, and they will be discussed in this chapter… There are several types of schedules that will be discussed in this chapter but all contain activities. An activity is simply a task to complete. The scope or complexity of the activity is subjective to and dependent on the project and how the schedule will be used. An activity can be as detailed as “paint base coat on west wall of room 101” or as general as “building skin.” Milestones are zero-day duration activities that mark important events in the project schedule. The notice to proceed or substantial completion are common milestones. Activities are often categorized as being design, procurement, or construction activities. More will be discussed on those later in the chapter… The Gantt chart is the simplest of the scheduling tools used in construction. It is a bar chart where each of the bars represents a task or activity. The tasks may be very detailed and short in duration or represent very lengthy activities or phases of construction. The activities that the bars represent may include periods of inactivity. For example, procuring doors may be an activity shown as a solid bar; however, most of that time is simply waiting for the doors to arrive. Oftentimes, this period of inactivity is indicated by dashed lines…Gantt charts are often used to show other time-dependent information besides the progress of an activity. Examples of this may be the number of worker hours expended or the construction costs. This is commonly shown graphically as a lazy S, where the x-axis denotes time and the y-axis denotes the additional information. The greatest strength of this type of chart is its simplicity in creation and how it displays the information. The most significant disadvantage is the lack of logic or relationships between the activities. This weakness limits the number of activities and the complexity of information shown…Network diagrams are an evolution from the Gantt chart and incorporate logic and relationships with the activities. One type of network diagram is an activity on arrow network, or simply arrow network. These types of diagrams use arrows to represent an activity and a node to represent a point in time…In this example, the nodes are represented by circles and are labeled by number. Each of the nodes represents a point in time in which an activity ends and another can begin. As the name suggests, the activities are represented by the arrows. In this example the activities are represented by letters A through E. The nodes provide logic to the diagram. Activities C and B cannot start until activity A is completed. Similarly, activity E cannot start until activity C and D are completed… Another type of network diagram is an activity on node network. Precedence diagrams are used commonly in construction and are an advanced form of this type of diagram. Activity on node diagrams use arrows to represent the logic or relationships between the activities. Activities are represented by the nodes. Activities on node diagrams are much more commonly used in construction than arrow networks….”
After the success of the Toyota Company in the 1970’s and 1980’s there was a concerted effort for many manufacturers to adjust to the “Lean” model and this meant manufacturers and suppliers would provided “just-in-time” material. This meant the car manufacturer would only receive the material needed to produce the vehicles produced that day, and the vehicles produced that day would be immediately shipped out to distributors. Toyota’s “lean” program allowed them to eliminate the overhead produced by managing and tracking unused inventory as well as dealing with shrink from damaged or misplaced inventory. As other companies began to adopt these processes, more materials became special order or made to order items. This means a Tulsa commercial contractor must have flexibility built into to every schedule because some material maybe difficult to get or need to be ordered at the very beginning of the project to ensure timely arrival. There are certain parts of a project that can have very little to no flexibility. The AIC furthers describes scheduling as follows:
“… The first step to schedule a project is to break down the project into manageable activities. Although critical, there is no one correct method for determining how many activities or the level of detail that the project is broken down into. The breakdown is largely based on the scheduler’s preference and experience; however, the number of activities and the detail should align with how the schedule will be used. The more activities included, the more detailed and precise the schedule will be. However, this will also increase the complexity of the schedule and the time needed to maintain it. A simpler, less detailed schedule will be easier to update but won’t provide as much information. Generally speaking, factors that should be considered when creating activities are phases, location (floor, wing, building, etc.), who is responsible for completing the activity, major cost items, activity duration, lead times, and critical path. The work breakdown structure is a valuable tool used to develop the schedule.
The second step in the scheduling process is to determine the duration of each activity. Activities should be broken down so they have a consistent range of durations. These durations can come from published sources such as R.S. Means or from a company database. It is also a good practice to get the feedback from the subcontractors performing the work and seasoned company personnel to ensure reasonable activity durations. The third step is to determine the relationships and constraints between the activities. There are four types of relationships used with network diagrams…”
Tulsa commercial contractors began each procurement to a project by breakdown the activities during the bidding or budgetary phase and these breakdowns often flow from bidding/budget to planning and procurement.