Commonway
Version V. 2026.08.31

Curb

ELM-CRB-01
Recommended Element

Curb

The raised edge separating the roadway from the sidewalk or shoulder, marking the physical boundary between space allocated to vehicles and space allocated to pedestrians or the roadway edge condition.

Working assessment: this pattern’s status reflects a preliminary Commonway System judgment call, pending final review.

#Why this pattern exists

The curb is the single most foundational physical element separating modes on a street; its height, material, and continuity determine drainage behavior, accessibility, and how legible the vehicle/pedestrian boundary reads to everyone using the street. Nearly every other Element pattern in this family (extensions, ramps, cuts) is a modification or interruption of this base condition, so it needs its own definition first.

#Key considerations

  • Height should be sufficient to discourage casual vehicle encroachment onto the sidewalk while not creating a tripping hazard where pedestrians cross it
  • Material and profile should be durable against snowplow damage in climates where that applies
  • Continuity matters: an interrupted or inconsistent curb line undermines drainage design and the clarity of the mode boundary

Curb Extension (ELM-CBE-02), Curb Ramp (ELM-CRP-03), Curb Cut/Driveway Apron (ELM-CCA-04) (all modifications of this base element); Crosswalk (ELM-CRW-08) (a common interruption point)

Unsourced claim

Formal citations for this pattern have not yet been compiled from primary sources.

Suggest changes to this page (opens in new tab) Last updated August 31, 2026