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Concrete Joint Abbreviations and Linetypes on Drawings

Last updated July 29, 2026

By YZ
For my concrete plan and elevations what lines and codes should I use for concrete joints? Joints can be shown as follows:
Joint type Abbreviation Linetype
Construction joint—general CJ Continuous thin line - the linetype for a general construction joint
Construction joint—straight CJ(S) Dashed thin line, with dash length s of 1 mm minimum and gap q of 2s to 4s
Construction joint—dowelled DCJ Chain thin line, double dashed: dash s of 1 mm minimum, gap q of 2s to 4s, long element p of 3q to 10q
Construction joint—keyed KCJ Chain thin line, single dashed: dash s of 1 mm minimum, gap q of 2s to 4s, long element p of 3q to 10q
Isolation joint IJ Continuous thick line - the linetype for an isolation joint
Contraction joints—keyed KJ Chain thin line, single dashed: dash s of 1 mm minimum, gap q of 2s to 4s, long element p of 3q to 10q
Contraction joints—dowelled DJ Chain thin line, double dashed: dash s of 1 mm minimum, gap q of 2s to 4s, long element p of 3q to 10q
Contraction joints—sawn or trowelled joint SJ Dashed thin line, with dash length s of 1 mm minimum and gap q of 2s to 4s
Expansion joints —dowelled DEJ Chain thin line, double dashed: dash s of 1 mm minimum, gap q of 2s to 4s, long element p of 3q to 10q
Expansion joints —keyed KEJ Chain thin line, single dashed: dash s of 1 mm minimum, gap q of 2s to 4s, long element p of 3q to 10q