Detailed design, which takes on and develops the approved conceptual design, is a stage where the design is refined and plans are set. The result of the detailed design is the complete and precise physical description of all parts of the structure (the blueprints) and how they are fit together. It also involves the investigation of the stability, strength and rigidity of the structure to be built, based upon the physical requirements of the building and an understanding of the structural performance, materials, and geometries used.
Adequate detail must be provided by the drawings and the report to permit reasonably accurate estimates of construction, operating cost, and the construction scheduling. Revisions to construction materials, machinery, and equipment specifications are made. The final design report should contain updated schedule, cost estimates, and specifications.
So, the detailed design serves as the basis for the construction phase. Appropriate cut in entire project cost can be made at this stage. Additionally, the detailed design needs to ensure that the design solution satisfies objectives of the project. Finally, it is necessary to verify at the end of the final design stage that the project remains economically viable.
Detailed Design Contents
The completed detailed design needs to involve the following components :
- Overall layout.
- Structural plan sections, elevations, and specifications. This involves the location of all structural elements in relation to gridlines, dimensions and sizes of beams, columns, walls, and slabs, sketch details of junctions and proposed fixings, superimposed loading allowances for each floor slab, the proposed discipline for all holes giving range and sizes permissible, and an outline specification including total weights of reinforcement
- Road layouts and landscape
- Horizontal and vertical circulation routes
- Operational flows and departmental operational policies.
- Building dimensions and gridlines.
- Architectural plans, sections, and elevation of buildings block plans, site plans,
- Elements of design that require early choice of manufacturer.
- Requirements for mock-ups, testing, samples necessary to satisfy performance requirements.
- Key assemblies, component drawings, and schedules with special attention to junctions and interfaces between elements that influence the structural or service designs. Key assemblies include external walls, lining, cladding, roofing, floor construction and finishes, staircases.
- Building service plans, sections, and elevations showing plumbing, drainage, ductwork, heavy pipework, light pipework, and access requirements.
- Define phases if the project is to be phased.
- Safety strategy.
- Fire strategy including compartmentalization, separation, protected shafts, surface spread of flame and escape strategy
- The use of materials and the potential for recycling and waste handling.
- Risk assessment.