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Drafting conventions: material representation, symbols

Materials

Representation of materials on working drawings has two primary purposes:

• to indicate that a particular material corresponds to a particular portion of the object;
• to indicate a particular arrangement or pattern of that material, e.g., tile pattern and colors on a floor surface.

It is often useful to reinforce the material symbol with a notation.

It is usually sufficient to put the material symbol on only a portion of the region where that material is present (i.e., use minimum means to indicate what is intended); the exception is where the specific pattern needs to be conveyed.

Plans: At small scale, up to 1/4"=1'-0", plans probably don't use material symbols in walls; at larger scales, the exterior cladding material or bearing wall material can be indicated with hatching or fill; floor or other horizontal surfaces are not generally shown with material symbols, as the finish schedule is usually sufficient for that purpose; enlarged plans, however, can show patterns of specific floor finishes.

Elevations and Sections: Material symbols are generally used.

Scale: The material symbol changes so as to be appropriate to the scale of the drawing, with more (and appropriate levels of) detail shown at larger scales.

Symbols

The UDS section on symbols is divided into divisions corresponding to the masterformat scheme, from "General Requirements (Division 01) to Plumbing (Division 22) and Pollution Control Equipment (Division 44).

Note that symbols may work, that is, they may represent something on a drawing, by one of several means:

• Association
• Resemblance
• Convention

Line weight conventions: Draw existing objects and symbols with a thin line; draw new objects with a medium line; draw things to be removed, or demolished, with a medium dashed line.

Symbol types: There are six symbol types:

• Identity: These indicate particular objects like fire alarms, exit signs, etc. They are independent of scale.
• Line: These indicate continuous things like walls or ducts; the number of lines is often scale dependent (e.g., a duct may appear as a single or double line, depending on the scale of the drawing). Lines can be solid or dashed, and are sometimes interrupted with a letter code, e.g., to identify a utility line. In the latter case, they are scale independent.
• Material: See notes above. Use with discretion, but use material symbols to clarify transitions from one material to another.
• Object: Scale dependent symbols representing the actual objects being symbolized, e.g., doors with swings shown, or windows, toilets, etc. Scale dependent.
• Reference: This category includes things like section, detail, or elevation indicators, i.e., symbols that point to another part of the drawing set, or give information about the drawing context (e.g., titles, north arrows, leaders, dimension lines, etc.).
• Text: Well, OK. "These symbols graphically indicate a word or words..."

Location of symbols in UDS: based on Masterformat, even if the symbol is used in another context. For example, a sink is a "plumbing fixture" (Division 22) even if shown on an architectural floor plan.