Specifications are written documents that describe the materials and workmanship required for a development. They do not include cost, quantity or drawn information but need to be read alongside other contract documentation such as quantities, schedules and drawings.
Written information about materials and workmanship should not appear on drawings or in bills of quantities as this can result in contradictory specifications and can cause considerable confusion, instead they should refer to the appropriate clauses in the specification.
The first stage in the development of a specification is the preparation of an outline specification. An outline specification is a brief description of the main components to be used in construction. They should be described in sufficient detail to allow the cost consultant to prepare some approximate quantities.
Components might include:
- Cladding (including external windows and doors).
- Internal walls and partitions.
- Internal doors.
- Building services (including lighting, heating, ventilation and air conditioning, water supply and drainage and other special installations).
- Fixtures and fittings (such as sanitary fittings).
 Related articles on Designing Buildings Wiki
- Bills of quantities.
- Common Arrangement of Work Sections.
- Contract documentation.
- Cost consultant.
- Insulation specification.
- Output-based specification.
- Performance specification.
- Procurement route.
- Production information.
- Project brief.
- Specification basics.
- Tender documentation.
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