Guide Specifications

This is an encore of an article Michael Chusid wrote over 20 years ago. Since then, an increased percentage of guide specifications have been written in accordance with CSI formats and principals, and there are now large, online databases of proprietary specification guide specs. Guide specs remain an important part of your sales collateral.

One of the most useful pieces of product literature an architect can receive from a building product manufacturer is a well written guide specification for the product. Along with product data sheets and suggested details, guide specifications can simplify the process of evaluating a product and incorporating it into a project's construction documents.
Proprietary guide specifications fill a need not satisfied by commercially available master guide specifications such as Spectext or MasterSpec or by an architectural firm's in-house master specification. While these standard references are sufficient for most projects, they do not always provide an adequate basis for specifying a particular manufacturer's product. Some master guide specifications try to generalize about products manufactured by several suppliers, requiring only the lowest common denominator of features and performance. In the process, they become "generications" instead of "specifications." Furthermore, there are far more products available than can be included in even the most comprehensive master guide specification, and new products are introduced faster than master guide specifications can be up-dated.

For example, use of preformed metal roofs is rapidly increasing. Yet there are few standards that apply to the diversity of metal roofing systems. MasterSpec's Section 07410 - Preformed Roofing and Siding is so broadly written that it requires considerable effort to edit it for a particular product or product type. Spectext, perhaps realizing the complexities of the product category, does not include a section for preformed metal roofing. For specifiers who lack either the time or inclination to thoroughly research and write a metal roofing specification from scratch, a manufacturer's guide specification can serve as the basis for preparing a project manual, helping a specifier to save time and avoid errors. While the availability of a guide specification is not a reason an architect would select a product, the lack of one could be a reason for an architect to decide not to use a product. Yet despite the importance of guide specifications, an informal survey of them shows that about half are defective.

Product vs. Guide Specifications

Many manufacturers fail to recognize that "product specification" is not the same as "guide specifications." The former is a manufacturer's description of a product he would like to sell and is written in the supplier's voice. A guide specification, on the other hand, does not describe a product so much as it does a set of requirements for the building into which the product is to be incorporated; it must be written in the architect's voice. In addition to product information, a guide specification must suggest specifications for the administration and execution of the work, related materials, and cross-references to other specification sections and the drawings.

If a guide specification is to be useful to an architect, it must be written in accordance with the  Construction Specifications Institute's principles and formats. Yet many manufacturers display a lack of familiarity with CSI's percepts. For example, CSI recommends that the name of a manufacturer or brand be listed only once in a specification in order to avoid repetition. Yet some manufacturers attempt to insert their name and brand into every paragraph.

Guide specifications should be flexible and easy to edit so they can be used with a variety of building types and project constraints. The guide should also identify product options and other decisions that the specifier must make. By providing notes explaining product options and how to coordinate a product with related work, a guide specification can take a specifier step by step through the decision-making process appropriate to a product.

Guide specifications are usually written to reduce the manufacturer's product liability. But a good guide should also protect the manufacturer's customers from professional liability and construction claims by suggesting specifications that anticipate and avoid potential problems. For example, a guide specification for Fabtec's CURA Adjustable Spacer for Metal Reroofing provides a framework within which a specifier can assign responsibility for coordinating each aspect of the product with related work and the existing roof deck. While following a manufacturer's recommendations may somewhat reduce a design professional's liability, architects should remember  that they must determine the suitability of a product and edit a guide specification to satisfy project requirements. And, as with all product literature, an architect should check to see if a guide specification is still current before using it.

By fully specifying the characteristics that distinguish a product from its competition, many manufacturers hope to make specifications for their product resistant to substitutions. But manufacturers should avoid specifying minor product features or performance requirements just for the purpose of blocking the competition. A better approach is demonstrated in a monumental' window guide specification published by ModuLine Windows, Inc. Its specifications provide a fair basis for specifying monumental windows and even names two competitors as acceptable substitutions. ModuLine's strategy is that it is far better to compete against firms with similar quality and pricing than it is to compete against substandard substitutions.

Since most architects use word processing to prepare specifications, manufacturers are increasingly distributing guide specifications on computer diskettes. A few companies are even experimenting with "expert systems" that partially edit or assemble a guide specification based on the products selected for a project or a specifiers responses to a checklist of questions. CSI now distributes a diskette library with Spec-Data* and proprietary Manu-Spec* guide specifications. Eventually, computerized specification writing systems will include proprietary guide specification sections.

*These programs are now moribund.

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By Michael Chusid, originally published in Progressive Architecture, ©1990