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Cad Drawings Symbology and Composition

Line types

Use standard linetypes whenever possible. Contour lines, dashed lines and other fonted lines shall be made of one continuous line segment, not a series of separate line segments. If the consultant is using pre‑approved basic CAD software other than AutoCAD, insure that linetypes translate correctly in the .dwg file.

Polylines with increased width may be used only to depict non‑building drawing elements such as cut‑lines. Use of toned or pochéd lineweights for use with inkjet or electrostatic plotters to differentiate new or existing work is acceptable.


Line type scale

Line type scale must be set so that each line type is recognizable, easily identified, and distinguishable to individuals who are working in the model files and in final plotted output.

Line weight and color

Consultants may use additional line weights as needed for effective communication of the project data.

Line weight and color affect the usability of CAD data in different ways. Line weight typically is most useful when working with plotted CAD drawings. Plots, or reproductions of plots, are usually monochrome and the thickness of lines is an important means of communicating information about the facility and the design.

Color is most useful when working with CAD data on a computer screen. Colors allow users to readily identify systems and types of information. On a computer screen, line weight often gets in the way of effective communication.


Text and Fonts

All text on University CAD drawings shall use only standard text fonts supplied with AutoCAD's font library.  CAD files submitted shall be plottable without modification and  with no additional software required.

Test size must be legible and appropriate to the graphic information presented and the intended plotted scale of the drawing.  Text must be in all upper case letters throughout a drawing, except for electrical switch legs and symbols which require lower case letters.

Text placement guidelines

Text usually should not touch other graphic objects, and must be placed with enough space around it to be legible when the drawing is plotted and reproduced.

Text may be placed at an angle. It must be readable from the bottom or right edges of the plotted sheet. Generally text should be placed at an angle of 0° or 90°. Text may be placed along (above or below) another element at an angle other than 0° or 90°.


English (Architectural in AutoCAD) units shall be the standard system of measurement. The base unit shall be inches.  (mm)



Annotation can be placed in either model files or sheet files. Annotations related to model data, such as dimensions, notes, and callouts must be included in the model file where they are easier to coordinate and revise.

Other annotations, such as drawing titles, legends, and sheet‑specific notes, are more convenient to work with when placed in the sheet file.



The default settings for AutoCAD's dimvars should be used. Associative dimensions should be used.

Consultants should insure that all dimensions are in a named dimension style for all dimensions in CAD files, so the dimension parameters can be readily modified as needed.


Xref (External Reference) Files

Xrefs may be used to subdivide a large CAD drawing into several smaller, more efficient drawings. The use of this procedure will reduce drawing size, increase performance, improve operator efficiency and make coordination of disciplines easier. Xrefs may also be used to split a drawing by disciplines.  When possible, avoid nested xrefs. There shall be no specific drive or directory references associated with the xrefs. All xrefs must reside in the same directory as the drawing files.



Any graphic entity that occurs repeatedly in drawings should be made into a block. Insertion points for blocks shall be consistent with its placement in the drawing. Use a logical insertion point (center of circle, bottom left corner of object, etc.). Keep names simple and descriptive. AutoCAD block names must be unique within each project.

Nested blocks contain more than one block definition. Nested blocks are permitted but should be avoided whenever possible.



Do not use polylines with increased width as a replacement for poché or hatching. Use pattern hatching sparingly since the practice significantly increases the AutoCAD entity count of a drawing (if using versions prior to AutoCAD Release 14).

Cad Drawings ,Project Mechanical Layer Names
Cad Drawings ,Project Plumbing Layer Names
Cad Drawings ,Project Fire Alarm Layer Names


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