WHAT IS THE PURPOSE OF A SPECIFICATION???
A specification along with the drawings (including schedules etc), form the part of the contract documents that translate the client's requirements into the eventual building/construction.
There are a number of definitions of the term specification - two of the best are:
- A detailed description prepared by a consultant Engineer or Architect to tell the Contractor everything about workmanship which cannot be shown on the drawings. (Scott 1964)
- The document that prescribes the requirements with which the product or service has to conform (possibly Gelder 2001)
Further definition between drawings and specification includes:
- Specifications, the textual or written description of the works, provide the definitions of quality and process.
- Drawings, the complementary graphical description of the works, define quantity, position, assembly and extent. (Gelder 2001)
Although the primary purpose of the specification is as a contract document, it does also get used for other secondary purposes. For instance, in New Zealand the Building Act 2004 section 45.1.b), requires a specification to be submitted with the plans as part of a building consent application. This is often confused with all the other documents that the BCA requires under section 45.1.a) of the Act. Other secondary uses of the specification can include maintenance reference for facility managers and record/as-built for historic reference etc.
A specification is essential to get a building properly built, whether it is a separate document or written on the drawings. And a well written specification can be easier for the Contractor and better for the designer and client.