The use of Codes and Keynotes has gained popularity in documentation as the benefits become more broadly appreciated. For example CPT1 = Carpet type 1 or RS01 = Roof sheet type 1.
Hobbs + Associates recommends the use of Codes in documentation as a means of reducing likelihood of conflicts and redundancy, and to improve the connection between the specifications and the drawings.
1) Allocate a Code to each material and assembly in the design, both exposed and concealed, such as Insulation.
2) Allocate Codes also to Assemblies which assemblies may consist of other materials which in turn have Codes. For example, a window assembly has code in which the glass and the aluminium finish also have codes. Another example is a set of differing Screen assemblies, which may share infill components which each have a code.
3) Use a Selections Schedule to described the material intended by each code. Columns for a schedule could include the following:
4) Adopt a clear and consistent format (syntax) for the Codes. For example:
5) Abbreviations are different to Codes and can be used in combination with them on drawings. Abbreviations are intended for generic references to materials or elements whereas Codes always refer to a particular selection as described in the Selections Schedule.
6) When developing a set of Codes for your project, consider the difference between “Logical” and “Physical” codes:
7) And finally, it pays to be clear what is the purpose of each drawing and add Codes accordingly. For example:
* Terms: “Codes” may also be referred to as “Keynotes” or “Labels” depending on local practice or the BIM program being used.