Building Drawings Checklist: Architectural Drawings - National ...

CBECWNG DIMENSIONSThe dimensioning method should be consistent, meticulous and inaccordance with the I-Jatforial Standards of Canada CAN 3-B 78.3-M77Building Drawings.1.1 Linear dimensions should be expressed in millimetrres (mm) onbuilding drawings, and in metres (m) on site plans. According tothe standard convention 5n drafting, the unit symbol can be omittedif the follming requirements are met:a) a note indicating the unit used is displayed in a conspicuousplace on the drawing sheet;bl all linear dimensions including those for spot levels and landelevation contours are given in one dimensioning unit only.For easier readlng, group the digits in triads on both sides of thedecimal marker (e.g., 123 456 789). All dimensions shown in metres mustbe taken to three decimal places, even when all deciraals are zeros(e'g., 1.235, 1.000).1.2 Area dimensions should be expressed fa:a) hectares (ha) for areas on survey plans, plans of subdfvLsfonsand lot plans to three decimals (e,g, , 1.234 ha).b) square metres (m2) for floor areas of rooms, cross-sectton areasof earthworks, large glass panes, etc. , to two decimals (e.g.,1.23 m2).c) square rnillimetres (min2) for structural areas and othersections, bars, etc., using no decimals.Symbola of these units MUST ALWAYS 33 SHOWN on drawings whereappropriate.1.3 Volume dimnsions should be expressed in:a) cubic metres (m3) for volumes of earthwork, excavations,concrete, fluids in large quantities, etc.b) litres (L) for volumes pertaining to containers of fluids orgases only.Symbols of these units MUST ALWAYS BE SHOWN on the drawings.