Curb (road) - Types of Curb - Material

Material

Curbs may be constructed of many materials, including asphalt, stone or masonry blocks, but most often are made of Portland cement concrete. The type of material may depend on the type of paving material used for the road and the desired function or need. For example, a Portland concrete curb used with an asphalt concrete pavement provides a highly visible barrier at the edge of the pavement. Other types of curb material include stone slab, cobblestone, and manufactured pavers.

Concrete curb may be constructed by setting forms by hand, filling them, letting them set up, and then removing the forms. When large quantities of curb are to be constructed, it is often more efficient to use a slip form casting machine. Curbs can also be precast at a central location and trucked to the construction site.

Asphalt curb is made with a paving machine. It can be cheaper if it is formed at the same time that a road is paved, but is less durable than concrete curb.

Stone curb, often made from granite, is durable and resistant to deicing salt. It is also chosen for aesthetic reasons. In areas where granite is available, it may be cost-competitive with concrete curb. One disadvantage is granite curb can cut a tire sidewall if rough-faced curb is used.

Belgian block curbs are made by placing blocks over a concrete slip. Then, concrete is wedged in between each block to hold them together. These blocks can be vertical or angled in order to create a mountable curb.