Promoting collaborative working within the construction industry
The term 'specification' can mean type of process, information, or document:
The specification process is independent of the form of contract used and who employs the various designers who contribute to it. Under traditional forms of contract most of the specification process will be pre-contract, but with forms that involve design by the contractor much of it will be post-contract.
Specification information is produced and used at all stages of design and construction, and may be included in many types of document, e.g.:
At the early stages of a project the specification information will be mainly in terms of the required performance. During succeeding stages it becomes increasingly prescriptive.
This Code of Practice is concerned with production specification, which is defined as: 'written information prepared by the design team for use by the construction team, the main purpose of which is to define the products to be used, the quality of work, any performance requirements, and the conditions under which the work is to be executed.'
A drawing consists principally of graphic information, it's primary purpose being to show by means of lines, graphic symbols and dimensions the size, shape and location of the building and it's parts. Drawn information and specification information are therefore complementary, and the relationship between the two should be kept clear and simple.
Descriptive annotation on drawings can give rise to problems, and should be minimised by systematic cross-referencing to the specification document - see the recommendations of this Code in Section 2.2.3. A key convention in this is the Common Arrangement of Work Sections (CAWS), described in greater detail in Section 4.1.2.
Location schedules are traditionally included in sets of production drawings, giving the details and locations of ironmongery, finishes, sanitary fixtures, etc. The essential reason for this information being regarded as drawings is that it's 'matrix' format invariably required it to be on large sheets of paper.
The information on such location schedules is usually production specification information (see definition at 3.1.1 above) and should, logically, be included in the specification document. If the information is formatted with some forethought, it can and should be given on A4 paper as part of the specification or schedule of work, removing the need for 'drawn' schedules.
The way this is done will depend on several factors, but particularly the size and complexity of the project and whether a specification (see Section 4.1.4) or a schedule of work (see Section 5.1.5) is used.
Production specification (in conjunction with drawn and measured information) should define the quality of the systems, products, workmanship and finished work such that all parties can have a reasonable degree of confidence that:
Production specification should be:
Specifications should be clearly and economically worded – the objective is to transfer information from designers to constructors with speed and certainty. Clarity and simplicity of style can save time for both specifier (when editing a basic text) and constructor.
Brevity can be achieved by using an economical style, judicious use of specification by reference, and saying only that which needs to be said, for example:
The CPI Production Specification Code 1987, Section 2, described the historical background, current standards, and objectives for future development of UK specification practice. In general, UK specification practice failed to meet the attributes listed in Section 3.1.4, and contributed little to the efficiency of the construction process and the quality of the built product. It was generally recognised that:
Specification practice in the UK compared very unfavourably with practice in other countries, particularly North America. The need to improve standards was widely recognised, and was seen to depend on the creation of an industry Code of Practice and the development and widespread adoption of suitable specification writing systems.
The 1987 CPI Project Specification Code and the development and uptake of the National Building Specification (NBS) have since underpinned a widespread improvement in specification practice on large and medium size projects. However specification systems suitable for small projects and building services have not been available or have not been widely taken up.
Sections 3, 4 and 5 of this CPI Code provide updated and extended guidance to prompt further developments in specification practice. Particular emphasis is placed on the use of suitable computer aided specification writing systems and other currently available IT resources that offer major potential benefits.