**The final design — known in Dutch as the definitief ontwerp (DO) and roughly equivalent to RIBA Stage 3 / 4 or HOAI Lph 3 — is the design stage in which the preliminary design is developed into a permittable plan with final materials, dimensions, colours and construction details.** It marks the end of the design phase and is the basis for the permit application, the tender and the specification.
Place in the construction process
A typical Dutch design process has five phases (STB 2014):
1. Initiation / feasibility 2. Concept design (SO) 3. Preliminary design (VO) 4. Final design (DO) 5. Technical design / specification (TO)
In the final design, material choices for joinery, services and finishes are locked in. Later changes are possible but become increasingly costly.
Contents of a final design
A typical final design includes:
- Plans, elevations and sections at 1:50 or 1:100
- Principle details (window junction, eaves, foundation) at 1:5 or 1:10
- Material schedule with final material and colour choices
- Building physics calculations (R-values, vapour balance, acoustics)
- Structural drawings with dimensions and reinforcement principles
- Services concepts for heating, ventilation, plumbing and electrical
- A cost estimate at final-design level
Application
The final design is the basis for:
- Permit application — permittable drawings and calculations
- Tendering — information on which contractors can quote
- Specification phase — development into construction drawings and the specification
A solid final design prevents major design decisions from being taken on site, where they are expensive and risky.
Related terms
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