4.2.1. Personnel Involved with Construction Site Utilization Planning
Typically, the project manager is responsible for developing SUPs [
12]. As shown in
Figure 2, this trend was observed in 46% of the respondents, while 29% reported that the site superintendent is responsible for developing the plan. Interestingly, only 17% reported that this process is a collaborative decision-making process where the project manager, site superintendent, and other management personnel are all involved.
Depending on project size and space availability, the number of subcontractors working on a project can be an important factor during the planning process. Respondents (61%) indicated that the number of subcontractors involved in a project does not influence the decision to develop a SUP. This suggests that many construction companies focus on the overall scope of the project versus the number of people carrying out construction-related tasks when deciding whether to develop SUPs.
When determining which subcontractors should be involved in the planning process, the planner must consider the project type, as well as specific tasks associated with the project. Based on survey responses, subcontractors that typically contribute information to the development of SUP include: structural (80%), foundation (72%), electrical (72%), plumbing (62%), and heating, ventilation, and air conditioning (HVAC) (54%). Respondents also noted that the civil/site work contractor should be consulted to determine whether site space will be needed for pipe storage, soil and aggregate stockpiling, or clearing and grubbing activities. To promote safe equipment operations, space requirements for excavation, grading, and earth moving activities should also be considered. By contacting all major subcontractors potentially requiring significant area for storage and/or equipment operations, a planner is more likely to perform a comprehensive assessment of the site when delineating space.
Before contacting subcontractors, a planner must know what to ask in order to obtain the information needed to prepare an accurate SUP. Although a variety of questions can be asked, the most common questions were (percentages indicate how often questions are asked): (1) what type of equipment will be on-site (80%); (2) how much on-site space is needed for storage (80%); (3) what tools sheds/job trailers will be on-site (78%); and (4) how many employees will be on-site (62%). A minority of respondents (4%) reported that they do not seek subcontractor input, but instead dictate the work conditions to the subcontractors. Utilizing subcontractor input certainly assists in SUP development; however, their request is not always achievable. To provide each subcontractor with sufficient site space, the planner should analyze all information gathered and allocate space based on scope of work and precedence. Once construction is underway, space adjustments can be made to compensate for the dynamic nature of the construction process.
Subcontractors are not the only individuals who can contribute useful information to SUPs. Owners, including individuals and organizations (e.g., universities, businesses, municipalities), can provide critical information that can directly affect the success of a project. Typically, 70% of project owners are involved with the SUP. Communication between project managers and owner/owner’s representative should be established prior to mobilization and maintained throughout the construction life cycle.
Information owners contribute can range immensely, depending on scope of work. In many cases, information needed to develop SUPs can be found within the contract documents. However, such documents may not always contain the information needed to properly locate TFs. As shown in
Figure 3, the following information was considered important when consulting the owner about SUP development: (1) preferred ingress and egress points (89%), (2) existing site conditions (75%), (3) construction traffic routes (73%), and (4) environmental concerns (52%). Owners may also indicate space limitations, preferred pedestrian routes, restricted areas, construction personnel parking, and major utility locations. Determining these parameters early in a project’s life cycle can help planners develop SUPs that satisfy the needs of subcontractors and owners. Maintaining a good relationship with the owner is critical, thus contractors should keep owners informed on site operations throughout a project.
4.2.3. Factors Affecting Site Utilization Plans
Space management involves three primary elements: site layout planning, path planning, and space scheduling [
4]. When beginning the CSUP process, the site layout planning team must determine the basic site space requirements based on the project scope, schedule, and construction method. The following discussion provides insight into these factors based on survey responses.
Temporary Facilities (TFs) play an important role in supporting construction activities over the duration of a project. The planner must understand the characteristics of each temporary facility before planning the site layout, as unsystematically placed TFs can significantly affect productivity [
25]. Many types of TFs varying in shape, size, and functionality can exist on a construction site. Respondents were asked to identify TFs considered during SUP development.
Figure 4 illustrates common TFs considered during the development process.
In addition to the TFs shown in
Figure 1, several respondents identified additional TFs, which include: crane locations and swing radii, concrete washout stations, emergency access points, first aid stations, construction fencing, toilet facilities, existing buildings, erosion and sediment control practices, and above ground utilities. Respondents also indicated that most TFs listed in the survey were applicable but not always used. Thus, one could conclude that TFs required for construction are based on project type, project location, and schedule complexity.
Site route planning is the process of delineating on-site space based on the transitional needs of equipment, material, and personnel from point A to point B. Respondents were asked to identify movement planning operations that are typically considered during site plan development. The two main operations considered were material movement (95%) and equipment movement (89%). On-site personnel movement (64%) was also considered but to a lesser extent. Based on these responses, it is apparent that most respondents understand the impacts that can arise from neglecting movement planning operations. Most likely, these elements are considered separately based upon project-specific characteristics.
Once TFs required for a project are selected, the construction team must determine the space requirements for each, as well as their locations within the construction boundary. This part of the planning process is intended to decrease congested work areas that result from trade stacking, mismanagement of material deliveries/storage, and poor waste management on-site [
26]. When asked about site space priority, 77% of the respondents stated that some subcontractors/trades do receive priority in site space allocation at some point during construction. This is particularly important when the amount of available site space is limited. In such instances, the construction team must give thorough consideration when determining which subcontractors/trades receive on-site space priority. This is often done based on project-specific characteristics such as manpower requirements, estimated quantity of work, production rate, site space availability, and cost considerations [
25]. Respondents indicated that structural contractors (61%) are the most frequent subcontractor/trade that falls within the space priority group, followed by electrical (48%); foundation (41%); plumbing (37%); and heating, ventilation, and air conditioning (HVAC) (37%).
It is imperative to realize that even though the subcontractors/trades listed above are recognized as priority groups over the course of a project, on-site space priority can vary between subcontractors/trades over time. For instance, the foundation and structural subcontractors may receive space priority early in the project; however, as the project progresses, space priority may shift to the mechanical, electrical, and plumbing (MEP) subcontractors to keep the project on schedule. Respondents pointed out that space priority is a function of critical path activities and any subcontractors/trades preforming critical tasks will likely receive space priority. Thus, it could be debated that subcontractor/trade space priority assessment is directly related to the project’s schedule, which in turn dictates critical activities.
The physical characteristics of each TF should be well understood before selecting its location on-site. The positioning of on-site TFs is directly linked to the site conditions and special relationships between construction activities, equipment, and material. In some situations, local by-laws, such as emergency access routes, may be controlling factors during the locating process [
25]. Project owners can also influence the location of TFs by providing specific site layout instructions within the contract documents to ensure their operational needs are met. Respondents were asked to identify the methods most commonly used to determine the locations of TFs within the construction site boundary. Experience obtained from previous projects, as indicated by 89% of respondents, was the primary method used for creating SUPs.
When designers are creating construction drawings, it is critical to include a high level of detail on the drawings so pertinent information can be clearly transferred between all stakeholders. Depending on the project size, the amount of detail needed cannot be effectively illustrated on a single drawing. Thus, construction drawings are usually categorized into phases (e.g., site, structural, MEP, etc.). This also holds true for SUPs. Respondents (71%) indicated they create multiple SUPs for different phases of construction as opposed to a single master site plan. This is necessary due to the ever-changing space requirements on-site. Surprisingly, 69% of the respondents develop SUPs for the entire project duration, not just the critical phases. This suggests that construction management teams have recognized the benefits of having a well-organized job site throughout the construction life cycle. While construction drawings are usually very detailed, SUPs are typically the opposite. A medium level of detail, indicated by 72% of respondents, is incorporated into SUPs with only essential TFs and storage locations shown on the plans.
The time it takes to develop a SUP is a function of the project scope and complexity. The majority of respondents (53%) indicated that time allocated to developing SUPs for most projects is between eight and forty hours. Knowing the typical amount of time spent on SUP development is important during project cost estimation. A project planner’s time is valuable and should be accounted for and effectively utilized. Understanding the time allotted for creating SUPs is important because it provides project estimators an avenue to quantify additional development cost.