Home    About BSD    Careers    Contact Us   Download SpecLink Evaluation Copy

building intelligence for intelligent building

quick links
Specifiers' Library Methods of Specifying Building Products

Most construction documents are written with the aim of obtaining competitive bids.  This may seem a bit obvious but we mention it because this affects how products are specified. To illustrate: if competitive pricing were not required, the simplest, most direct specification for a particular product would be to list its manufacturer and brand name. In contrast, in order to obtain competitive bids (or pricing), the construction documents need to specify products that at least two or three manufacturers make — this usually requires more details than just the manufacturer and model name. A competitive specification is commonly referred to as a "generic" specification.

A generic specification should not be confused with a "plain label" or "lowest common denominator" (i.e. cheapest) specification, because that could be far from the truth -- it is perfectly possible to specify high quality products generically provided more than one manufacturer makes an equivalent product. More accurate terms to use are "descriptive", "non-proprietary", or even "competitive" specifications.

A specification based on a single manufacturer’s product is usually referred to as a "proprietary" specification.  The term proprietary is not universally understood. Some people understand the term proprietary to mean that one or more manufacturers' names and/or brand names are listed explicitly in the specification. Others understand proprietary to mean that there is only one product that is acceptable -- i.e. "sole-source".

The confusion is compounded when a descriptive specification is accompanied by a listing of one or more acceptable manufacturers or brand names. It is probably most accurate to refer to the two principal types of specification as "competitive" and "sole-source".

Both competitive and sole-source specifications can be prepared using one or more of these techniques:

  • Descriptive
  • Performance
  • Reference standard
  • "Proprietary" (naming names)

CSI's Project Resource Manual / Manual of Practice (CSI PRM/MOP) describes these techniques in detail.

SpecLink referenced document SpecLink's product specifications are designed to be competitive. They usually use a combination of these specifying methods, as appropriate to the product category and the competitive environment. When manufacturer names are listed, at least three manufacturers of products of a similar level of quality are listed. When editing SpecLink specs, the specifier should be careful not to select a combination of product properties that results in a sole-source specification, unless that is intended.

Guide Specifications Furnished by Others

Particular care should be exercised when utilizing specifications prepared by other people. Unless they explicitly say so, it is difficult to tell at first glance whether the product specification is competitive or sole-source. Experienced specifiers usually assume that guide specifications furnished by building product manufacturers will be sole-source specifications no matter what specifying technique is used -- the fact that no names are named does not preclude the possibility that the only product that can comply with the description is the manufacturer's own product. In addition, a sole source specification can be "opened up" by the simple expedient of stating that substitutions will be considered.

The SpecLink Specifiers' Library is provided as a service to our customers by Building Systems Design, Inc.