8

The Meaning of Symbols

8.1 GENERAL INFORMATION.

Blueprint drawings—as applied to the building-construction industry—are generally used to show how a

building, object, or system is to be constructed, implemented, modified, or repaired. One of the main

functions of graphic symbols on construction drawings is to reference other drawings within the set. For

example, a circle drawn around an area of a drawing with an extension to a number would indicate that

this portion of the drawing has been drawn to a larger scale to provide more information than would be

possible at the existing scale (Figure 8.1). In the preparation of working drawings for the building-con-

struction industry, architects and engineers have devised systems of abbreviations, symbols, and

keynotes to simplify the work of those preparing the drawings and to keep the size and bulk of the con-

struction documents to an acceptable, comprehensible minimum. Drawing simple building components

without the use of symbols would indeed be a tiresome task. Visualizing and reading construction draw-

ings therefore necessitate a knowledge of symbols and abbreviations used in the construction industry

and of their proper use in representing materials and other components and their locations (Figure 8.2).

Symbols may vary slightly from one locale to another.

The majority of architects and engineers today use symbols adopted by the American Institute of Ar-

chitects (AIA) and the American National Standards Institute (ANSI). However, designers and drafters

continue to modify some of these symbols to suit their own particular needs for the types of projects they

are normally commissioned to design. For this reason, most drawings have a symbol list or legend drawn

and lettered either on each set of working drawings or in the written specifications. Modified symbols are

normally selected by the consultant because they are easier to draw and interpret and are sufficient for

most applications.

In order for this system of symbols to work, each drawing within the set has its own unique number.

This is usually a combination of numbers: the number for the individual drawing as well as the page or

sheet number on which the specific drawing appears. Individual drawings may be referenced many

times throughout a set of construction drawings. The symbols discussed in this chapter are not all-inclu-

sive by any means, but they are the ones that the builder or designer is likely to encounter in most gen-

eral building-construction applications.

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