Preliminaries in Construction 101

Within the realm of construction contracts, preliminaries play a crucial role in setting the foundation for successful project delivery...

Within the realm of construction contracts, preliminaries play a crucial role in setting the foundation for successful project delivery. Preliminaries, often included as part of tender documents, provide an extensive description of the project, specifying general conditions, requirements, and cost considerations that are essential for contractors and architects to assess accurately.

This article aims to provide a comprehensive guide to preliminaries in construction, shedding light on their purpose, components, cost assessment, and the significance of clear and well-defined preliminaries in the tendering process. By understanding the importance of preliminaries and following best practices in their development, stakeholders can enhance project efficiency, minimize disputes, and lay the groundwork for a successful construction endeavor.

Understanding preliminaries in construction

In the realm of construction contracts, preliminaries hold a significant role in providing a comprehensive overview of a project and establishing the framework for its execution. This section explores the fundamental aspects of preliminaries, their purpose, and their relationship with work sections.

Preliminaries definition

Preliminaries, also known as “prelims,” are a set of documents or sections within tender documents that describe the project as a whole. They outline general conditions, requirements, and administrative aspects necessary for the successful completion of the construction project. While preliminaries do not directly pertain to the specific work packages, they are vital for contractors and subcontractors to accurately assess the costs and factors associated with the project’s execution.


The primary purpose of preliminaries is to provide a comprehensive description of the project, encompassing its scope, objectives, and key requirements. They serve as a roadmap for all parties involved, ensuring a shared understanding of the project’s overall vision and guiding principles. Preliminaries also facilitate fair and competitive bidding by enabling suppliers to evaluate the costs associated with executing the project accurately.

Complementing work sections

Preliminaries work in conjunction with work sections to form a cohesive and detailed set of tender documents. While work sections focus on the specific packages of works required by the contract, preliminaries provide the overarching context and general conditions within which these works will be carried out. Together, they create a comprehensive document that outlines what is needed to complete the project as specified in the contract.

Key components of preliminaries

Preliminaries typically include various components, which may vary depending on the nature and complexity of the project. These components may include:

  1. Subcontracting: Preliminaries outline the procedures and requirements for subcontracting aspects of the project to other specialized contractors. This section may specify the criteria for selecting subcontractors, their roles and responsibilities, and the approval process for subcontractor appointment.
  2. Approvals and Testing: Preliminaries detail the necessary approvals, permits, and certifications required for the project, such as planning permission, building regulations compliance, and environmental assessments. Additionally, they may specify the testing procedures and standards to be followed during construction and commissioning stages.
  3. Completion Criteria: Preliminaries define the criteria and conditions that signify the completion of the project. This may include elements such as final inspections, handover documentation, and compliance with relevant regulations and standards.
  4. Other General Conditions: Preliminaries also cover various general conditions and requirements, such as insurance obligations, health and safety protocols, quality control measures, site access and security, and project-specific administrative procedures.

By including these components, stakeholders can ensure that all relevant aspects of the project are considered and communicated clearly to bidders, promoting transparency and minimizing potential misunderstandings.

In the next section, we will delve into the cost assessment and site overheads associated with preliminaries, shedding light on how they impact the financial aspects of the project.

Cost assessment and site overheads

Preliminaries play a crucial role in assessing project costs and managing site overheads in construction contracts. This section explores the connection between preliminaries and cost assessment, highlighting the distinction between preliminaries and specific work rates, and discussing the concept of site overheads.

Assessing project costs

One of the key functions of preliminaries is to assist in assessing the costs associated with the construction project. While specific work rates account for the direct costs of labor, materials, and equipment for each work item, preliminaries encompass the indirect costs and administrative expenses required for the overall execution of the project.

By considering factors such as subcontracting, approvals, testing, and completion, preliminaries enable contractors and subcontractors to develop accurate cost estimates that reflect the complete scope of the project.

Distinction from specific work rates

It is essential to distinguish preliminaries from the rates specified for specific work items. While specific work rates focus on the direct costs associated with individual construction activities, preliminaries cover the broader project requirements and associated costs that are not directly tied to a specific work package.

This differentiation ensures that all necessary elements, beyond the individual work items, are considered and accounted for in the overall project cost assessment.

Site overheads

Within preliminaries, a significant aspect to consider is site overheads. Site overheads encompass the general cost items and expenses incurred during the construction process, which are not directly attributable to any specific work item. These overhead costs include expenses related to the administration of the project, provision of general plant and equipment, site staff, facilities, and other site-based services.

Examples of site overheads may include project management and supervision costs, site establishment and welfare facilities, temporary utilities, safety and security measures, site-based testing and inspections, and general project administration expenses. These costs are essential for the smooth functioning of the construction site and contribute to the overall project execution and delivery.

Inclusion in preliminaries

Preliminaries provide a platform for capturing and allocating site overheads and general cost items. By explicitly including these elements within the preliminaries, the tender documents ensure that contractors and subcontractors can account for these costs when developing their bids.

This inclusion promotes transparency, helps avoid ambiguities, and ensures that all parties involved have a clear understanding of the financial requirements beyond the direct work rates.

The importance of clear and well-defined preliminaries

Clear and well-defined prelims in construction contracts are essential for fostering successful project outcomes. This section emphasizes the significance of establishing comprehensive preliminaries, discusses the benefits they offer, and provides best practices for their development.

  1. Minimizing Disputes: Clear and detailed preliminaries help minimize disputes and conflicts throughout the project lifecycle. By clearly outlining the project requirements, conditions, and procedures, preliminaries provide a common understanding among all stakeholders. This reduces the potential for misinterpretations, disagreements, and legal disputes that may arise due to ambiguity or omissions in project documentation.
  2. Enhancing Project Efficiency: Comprehensive preliminaries contribute to project efficiency by providing a roadmap for project execution. When all parties involved have a clear understanding of the project scope, requirements, and timelines, it enables better planning, coordination, and resource allocation. Contractors and subcontractors can align their activities and make informed decisions, resulting in smoother workflow, reduced delays, and improved project progress.
  3. Ensuring Successful Construction Outcomes: Well-defined preliminaries play a crucial role in achieving successful construction outcomes. They provide clarity on project objectives, quality standards, and completion criteria. By including specific requirements for approvals, testing, and compliance, preliminaries ensure that the project is executed in accordance with the desired standards and meets regulatory and contractual obligations. This enhances the likelihood of delivering a project that fulfills the client’s expectations and achieves the intended purpose.

Best practices for developing preliminaries

To ensure the effectiveness of preliminaries, stakeholders should consider the following:

Involving relevant stakeholders: Collaboration among clients, architects, engineers, and contractors is vital during the preliminary development stage. By involving all key parties, the requirements and expectations can be accurately captured, reducing the likelihood of omissions or misunderstandings.

Systematic approach: Adopting a systematic approach to identifying and including the necessary components within preliminaries is essential. This involves reviewing relevant regulations, project specifications, and industry best practices to ensure all essential elements are addressed.

Regular review and updates: Preliminaries should be regularly reviewed and updated as the project progresses. Changes in project scope, regulations, or client requirements may necessitate revisions to preliminaries to ensure they remain accurate and aligned with the project’s evolving needs.

Clarity and consistency: It is crucial to use clear and concise language when drafting preliminaries. Ambiguities or vague descriptions should be avoided to minimize potential misunderstandings. Additionally, maintaining consistency throughout the document ensures a coherent and cohesive set of requirements.

Understanding the importance of preliminaries and following best practices in their development, stakeholders can enhance project efficiency, minimize disputes, and lay the groundwork for a successful construction endeavor. Comprehensive preliminaries provide the necessary framework and guidance for all parties involved, facilitating a smoother project execution process and leading to the delivery of high-quality construction projects.

The role of preliminaries in tendering process

This next section highlights the significance of preliminaries in the tendering stage and explores how they contribute to fair and competitive bidding, as well as effective project execution.

  1. Ensuring Fair and Competitive Bidding: Preliminaries provide crucial information to potential suppliers, such as contractors and subcontractors, enabling them to prepare accurate and competitive bids. By clearly describing the project as a whole, including general conditions and requirements, preliminaries establish a level playing field for all bidders. This transparency ensures that all parties have equal access to project information, facilitating fair competition and promoting the selection of the most suitable supplier for the project.
  2. Comprehensive Project Understanding: Preliminaries help suppliers develop a comprehensive understanding of the project’s scope, objectives, and specific requirements. Through detailed descriptions of subcontracting arrangements, approvals, testing procedures, and completion criteria, preliminaries ensure that potential suppliers have a clear picture of the project’s complexities and constraints. This understanding allows them to assess the feasibility of the project, accurately estimate costs, and propose appropriate strategies for successful project execution.
  3. Promoting Accurate Cost Estimation: Accurate cost estimation is crucial for both clients and suppliers in the tendering process. Preliminaries play a significant role in this regard by providing detailed information on project requirements and associated costs. By including items such as subcontracting, approvals, testing, and completion criteria, preliminaries enable suppliers to develop more precise and realistic cost estimates. This enhances transparency in the bidding process and helps clients make informed decisions when selecting the most cost-effective and reliable supplier.
  4. Minimizing Project Risks and Uncertainties: Clear and well-defined preliminaries help minimize project risks and uncertainties during the tendering stage. By outlining general conditions, requirements, and administrative procedures, preliminaries ensure that potential suppliers are aware of the project’s contractual obligations and regulatory compliance. This reduces the likelihood of misunderstandings, disputes, and delays arising from ambiguities in the tender documents. Suppliers can evaluate the project’s inherent risks and plan accordingly, leading to more accurate bids and effective risk management strategies.
  5. Establishing a Framework for Project Execution: Preliminaries provide a framework that guides the project’s execution once the contract is awarded. The detailed descriptions of subcontracting arrangements, approvals, testing, and completion criteria help establish a common understanding between the client and the supplier. This ensures that both parties are aligned in terms of project expectations, timelines, and deliverables. Preliminaries serve as a reference point throughout the project, enabling effective communication, collaboration, and project management.

Through providing comprehensive project information, facilitating fair and competitive bidding, promoting accurate cost estimation, minimizing risks and uncertainties, and establishing a framework for project execution, preliminaries contribute significantly to the success of construction endeavors.

Stakeholders should recognize the importance of well-defined preliminaries and invest effort in their development to ensure a smooth and efficient tendering process, leading to the selection of the most suitable supplier and the successful execution of the project.

Best practices for developing preliminaries

This section outlines key best practices that stakeholders should consider when developing preliminaries, ensuring they serve their intended purpose and contribute to project success.

  1. Collaboration and Stakeholder Involvement: Effective preliminary development requires collaboration among all relevant stakeholders, including the client, architects, engineers, and contractors. By involving key parties in the process, a comprehensive understanding of project requirements can be achieved. Regular communication and coordination ensure that the preliminaries capture the collective expertise and align with the project objectives.
  2. Thorough Project Evaluation: To develop comprehensive preliminaries, it is crucial to conduct a thorough evaluation of the project. This includes reviewing project documentation, specifications, regulations, and any relevant industry standards. Understanding the project’s technical requirements, legal obligations, and desired outcomes helps in accurately capturing the necessary components within the preliminaries.
  3. Clarity and Consistency in Documentation: Preliminaries should be drafted using clear and concise language to avoid ambiguity or misinterpretation. Each requirement, condition, or procedure should be articulated in a manner that leaves no room for confusion. Consistency in language, terminology, and formatting throughout the document enhances its readability and ensures a cohesive set of preliminaries.
  4. Regular Review and Updates: Preliminaries should be regularly reviewed and updated throughout the project’s lifecycle. As project details evolve or new information becomes available, it is essential to incorporate these changes into the preliminaries. Regularly reviewing and updating the document ensures that it remains accurate, relevant, and aligned with the project’s changing needs.
  5. Detailing General Conditions and Requirements: Preliminaries should include a thorough description of general conditions and requirements. These may encompass subcontracting procedures, approvals, testing protocols, completion criteria, health and safety measures, quality control processes, and any other relevant general conditions. The level of detail provided allows suppliers to fully understand the project’s parameters and accurately estimate costs.
  6. Clarity on Site Overheads and General Cost Items: Clearly defining site overheads and general cost items within the preliminaries is essential. This includes identifying and outlining the costs associated with project administration, site-based services, general plant and equipment, site staff, facilities, and other related expenses. Providing transparency in these costs enables suppliers to consider them when formulating their bids, leading to accurate cost estimation and effective financial planning.
  7. Reviewing and Resolving Ambiguities: During the development of preliminaries, stakeholders should proactively review the document to identify and resolve any ambiguities or conflicting requirements. This may involve seeking clarification from the client, consulting industry experts, or engaging in collaborative discussions with relevant stakeholders. Resolving ambiguities ensures a clear understanding of project expectations and minimizes the potential for disputes or misunderstandings.

Developing clear and comprehensive preliminaries requires collaboration, thorough evaluation, and attention to detail.

By following best practices such as involving stakeholders, maintaining clarity and consistency, regularly reviewing and updating the document, detailing general conditions and requirements, clarifying site overheads and cost items, and resolving ambiguities, stakeholders can create preliminaries that effectively guide the project’s execution.

Well-developed preliminaries contribute to accurate cost estimation, effective risk management, and enhanced project coordination, ultimately leading to successful construction outcomes.

…in conclusion

Prelim’s play a vital role in construction projects, serving as a comprehensive guide that outlines the project’s scope, requirements, and general conditions. They provide a framework for accurate cost assessment, fair bidding, and effective project execution. By understanding the purpose and components of preliminaries, stakeholders can navigate the tendering process with clarity and confidence.

Throughout the tendering stage, clear and well-defined preliminaries foster fair competition among suppliers, ensuring equal access to project information and requirements. They enable potential suppliers to develop a comprehensive understanding of the project, assess costs accurately, and propose competitive bids.

Preliminaries also contribute to minimizing disputes, as they provide clear guidelines, reduce ambiguities, and establish a common understanding among stakeholders.

The inclusion of site overheads and general cost items within preliminaries allows for a comprehensive assessment of project costs beyond the direct work rates. By accounting for these indirect expenses, stakeholders can develop more accurate cost estimates and effectively manage project finances. This transparency contributes to informed decision-making and successful project outcomes.

Developing effective preliminaries requires collaboration, stakeholder involvement, and attention to detail. By following best practices such as thorough project evaluation, clarity in documentation, regular reviews and updates, detailing general conditions and requirements, and resolving ambiguities, stakeholders can create preliminaries that align with project objectives and facilitate efficient project execution.

What is the difference between prelims and overheads and profits (OH&P)?

Preliminaries and Overheads and Profits (OH&P) are both cost elements associated with construction projects, but they represent different aspects of project costs.

  1. Preliminaries: Preliminaries, also known as ‘prelims’, as discussed above are costs that are necessary for the execution of a construction project but are not directly related to specific work items. They include general administrative expenses, site-based services, and other project-related requirements that are essential for the overall management and coordination of the project. Examples of preliminaries may include project management costs, site establishment, temporary utilities, welfare facilities, site-based testing and inspections, and general project administration expenses.

Preliminaries provide a comprehensive description of the project as a whole, specifying general conditions and requirements for its execution. They allow contractors and subcontractors to assess and account for the indirect costs associated with the project, beyond the direct costs of specific work items. Preliminaries help ensure that all necessary elements for project execution are considered and accurately estimated.

  1. Overheads and Profits (OH&P): Overheads and Profits (OH&P) are a component of the overall project cost and represent the additional costs incurred by the contractor beyond the direct costs of labor, materials, and plant/equipment. Overheads include the indirect costs of running the contractor’s business, such as office expenses, staff salaries, insurance, and general administration. Profits, on the other hand, represent the contractor’s margin or markup on the project costs, which accounts for the contractor’s risk, expertise, and profitability.

OH&P are typically expressed as a percentage of the direct costs or the total project cost. The specific percentage can vary depending on factors such as the nature of the project, market conditions, and the contractor’s pricing strategy. OH&P serve as a means for the contractor to cover their overhead expenses and generate profit from the project.

In summary, preliminaries encompass the project-specific costs required for overall management and execution, while OH&P represent the contractor’s overhead expenses and profit margin on the project. Both components are essential in accurately estimating and accounting for the total cost of a construction project.

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