Tender drawings and IFC drawings (Issued for Construction) are both critical in the construction process, but they serve different purposes and are used at different stages of a project. Below is a detailed explanation of the differences between these two types of drawings:
1. Purpose
Tender Drawings:
- Purpose: Tender drawings are prepared during the early stages of a construction project and are used as part of the tendering process. These drawings provide potential contractors with enough information to prepare accurate bids or proposals for the project. The main goal of tender drawings is to communicate the design intent and scope of work so that contractors can estimate the costs, materials, labor, and time required for the project.
- When Used: Tender drawings are used during the tendering phase, which occurs before the selection of a contractor and before construction begins.
IFC Drawings:
- Purpose: IFC drawings are the final set of construction documents issued to the contractor once the tender process is complete and a contractor has been selected. These drawings represent the approved design and are used to guide the actual construction of the project. They include all necessary details, specifications, and instructions required for the construction team to build the project according to the client’s requirements.
- When Used: IFC drawings are used during the construction phase. They serve as the official reference for how the project should be built.
2. Creation and Responsibility
Tender Drawings:
- Creation: Tender drawings are typically created by the design team, including architects, engineers, and other consultants. These drawings are developed during the design development phase and provide a general overview of the project’s scope, layout, and key elements.
- Responsibility: The design team is responsible for producing tender drawings that accurately convey the design intent and scope of the project. These drawings may not include all the detailed information needed for construction but should be detailed enough for contractors to prepare competitive bids.
IFC Drawings:
- Creation: IFC drawings are also created by the design team but are developed after the tendering process. These drawings are based on the tender drawings but are refined and updated to include all the necessary details, specifications, and construction methodologies required for the actual construction.
- Responsibility: The design team is responsible for ensuring that the IFC drawings are complete, accurate, and fully coordinated across all disciplines (architecture, structure, MEP, etc.). These drawings are issued to the contractor as the final construction documents.
3. Level of Detail
Tender Drawings:
- Detail Level: Tender drawings provide a general overview of the project, focusing on the scope and design intent rather than the specifics. They typically include basic floor plans, elevations, sections, and key details, but may not cover every aspect of the project in detail. The level of detail is sufficient for contractors to understand the project and prepare their bids, but not for construction.
- Examples of Detail: Floor plans showing room layouts, basic elevations, sections, and overall structural and MEP layouts.
IFC Drawings:
- Detail Level: IFC drawings are far more detailed than tender drawings. They include comprehensive information on every aspect of the project, including precise dimensions, material specifications, construction methods, and installation details. IFC drawings are intended to be used directly by the construction team to build the project, so they must be complete and leave no ambiguity about how the work should be carried out.
- Examples of Detail: Detailed floor plans with dimensions, structural framing plans with connection details, detailed MEP layouts with exact routing and installation instructions, and full material specifications.
4. Timing in the Project Lifecycle
Tender Drawings:
- Timing: Tender drawings are produced during the design development phase, before the project is put out to bid. They are issued to potential contractors as part of the tender package, which also includes specifications, schedules, and other documents necessary for preparing a bid.
- Role in Process: Tender drawings are used to communicate the project’s scope and design intent to contractors, enabling them to submit competitive bids for the work.
IFC Drawings:
- Timing: IFC drawings are produced after the tendering process and after a contractor has been selected. They are issued before construction begins and are used throughout the construction phase to guide the building of the project.
- Role in Process: IFC drawings are used as the official construction documents, providing the construction team with all the information needed to build the project according to the approved design.
5. Review and Approval Process
Tender Drawings:
- Approval: Tender drawings are reviewed by the design team and the client before being issued as part of the tender package. However, they do not typically require the same level of detailed coordination or approval as IFC drawings because they are not the final construction documents.
- Changes: Changes to tender drawings are common, especially during the bidding process, as contractors may request clarifications or suggest modifications. Any significant changes would typically be reflected in the IFC drawings.
IFC Drawings:
- Approval: IFC drawings undergo a thorough review and approval process by the design team, client, and sometimes regulatory authorities. Once approved, these drawings are issued as the official construction documents. Any changes to IFC drawings after issuance must be formally approved and documented.
- Changes: Changes to IFC drawings during construction are possible but require formal approval through processes like Requests for Information (RFIs) or change orders. Updated drawings may be issued as revisions to the original IFC set.
6. Use in Construction
Tender Drawings:
- Usage: Tender drawings are not typically used for actual construction. Instead, they are used to obtain bids from contractors, allowing the client to select a contractor based on price, schedule, and other factors. While tender drawings provide a good overview of the project, they lack the detailed information needed for construction.
- Example: A contractor uses tender drawings to estimate the quantity of materials, labor, and time required to complete the project, which forms the basis of their bid.
IFC Drawings:
- Usage: IFC drawings are used throughout the construction phase as the primary reference for how the project should be built. The construction team relies on these drawings to ensure that every aspect of the project is constructed according to the approved design and specifications.
- Example: The construction team uses IFC drawings to position walls, install structural elements, and lay out MEP systems with precision, ensuring that the final build matches the design intent.
7. Examples of Each Type
Tender Drawings:
- Examples:
- Basic architectural floor plans and elevations showing the general layout and appearance of the building.
- Outline specifications or schedules for key materials and finishes.
- Preliminary structural plans showing the general arrangement of major elements.
IFC Drawings:
- Examples:
- Detailed architectural drawings with exact dimensions, material specifications, and installation instructions.
- Comprehensive structural drawings with full connection details, reinforcing schedules, and construction methods.
- Complete MEP drawings showing the precise routing, sizing, and installation details for all mechanical, electrical, and plumbing systems.
Conclusion
In summary, tender drawings are prepared during the design development phase and are used to communicate the scope and design intent of a project to potential contractors. They provide enough information for contractors to prepare bids but are not intended for construction. IFC drawings, on the other hand, are the final, detailed construction documents issued after the tender process is complete. They include all the necessary details, specifications, and instructions needed to guide the actual construction of the project. Understanding the difference between these two types of drawings is crucial for ensuring that the project progresses smoothly from design to construction.
