Kidosaki House designed by Tadao Ando / Section drawing by Otto, A. Chanyakorn

Line type is one of the drawing elements that should be learned.  Each line type serves a purpose in drawing, and they also convey their own meaning in architectural drawings. Thus, in order to fully convey our communication in drawings, we should understand its functions.  I normally employ four line types in my drawings, and I personally enjoy the simplicity of utilizing only these four line types. Whether drawn on a computer or by hand, these line types help to convey  meanings in architectural graphic . Drawings are easier to read and interpret when line types are properly applied. The line types below are commonly used in my work:

Continuous lines use for cut and visible edges of objects. They allow depict the form of objects. Continuous lines also use for dimensional purposes. The use of line width for continues line is varies (Please see line width article for more detail).

Dashed lines represent concealed edges of objects, or elements that being removed for our view. I normally use dashed line with thin line width. Dashed lines also commonly use with thin line width.

Dot-dashed lines use for gird section line, building axes, centerlines.

Dotted lines indicate the edges of object lie above the cut plane in floor plan drawing or section plane. Since the dotted lines are difficult to see when we depict them with thin line width, I normally use medium line width for dotted-lines. I found it was difficult to use dotted lines when drawn by hand. Thus, I replace them with dashed lines instead.