A curb is an edge treatment, typically raised, where the roadbed meets the sidewalk or other raised pathway. Curbs serve three functions: a gutter to convey rainwater and detritus from the roadbed and sidewalks to the catch basins at the ends of the street; a visual and physical limit to the vehicular roadbed; and a finished edge to sidewalks and roadbeds.
Cast-in-Place Concrete
This is the standard method for installing concrete curbs. The mixture is comprised of cement(s), aggregate(s), water, and other possible chemical admixtures, such as air entrainer and pigment. When the mixture is finished, it is allowed to harden, forming a solid curb. Concrete curbs can be pigmented to match the adjacent sidewalk.
Cast-in-Place Steel-Faced Concrete
Steel facing provides additional protection to a Cast-in-Place Concrete Curb and is typically utilized in areas with significant vehicular traffic such as along bus or truck routes.
Integral Curb and Gutter
This treatment is commonly used in very flat areas where drainage is a challenge. The curb and first 6-12 inches of the roadway are poured together to create an integral concrete structure. The concrete gutter and curb act to maintain positive drainage to the nearest catch basin and ensure that grading will be maintained over time when compared to the adjacent asphalt roadway.
Granite
Granite cut to long sections and laid as curbing. Saw-finishing, achieved by cutting the granite with a stone saw and polishing out saw marks, provides a smooth, clean look. Split finishing, typically achieved by hand-chiseling, exposes the natural cleft of the stone, giving a rough-hewn texture.