Screened lines are finely dotted lines that appear lighter than other lines on the drawing. Screened lines do not appear screened in the CAD file, but rather are produced by the plotting software.
Screened lines are used to show either existing features, features that are not a part of the specific drawing discipline, or features that are not in the contract. Examples of the use of screened lines follows.
Site plans almost always show the existing site features, trees, contours, roads, etc., with screened lines. Only the new features that are part of the proposed construction, are shown with bold lines.
A mechanical plan view of a pumping plant generally shows the building outline in screened lines. Only the mechanical features, piping, valves, etc., are shown with bold lines.
A lighting plan shows the background of the building in screened lines, including all structural and mechanical features. Only the lighting and wiring are shown with bold lines.