concrete. Before the paver was made from concrete, either real stone or a clay product was used. The first production of concrete pavers in North America was in Canada, in 1973. Due to their success, paving stone manufacturing plants began to open throughout the United States working their way from East to West. The first concrete pavers were shaped just like a brick, 4” by 8” (10 cm x 20 cm) and they were called Holland Stones. These units turned out to be economical to produce and were exceedingly strong. In addition to being economical, interlocking concrete pavers are also widely available in water-permeable designs, which have added ecological benefits. By allowing water to drain through the pavers in a way that mimics natural absorption, builders and landscapers are able to limit surface runoff and prevent soil erosion or buildup of standing water in the surrounding land area. Some permeable paver installations are designed to harvest rainwater, which can then be repurposed for uses such as irrigation or washing a car. Stone pavers A stone paver is another type of paver. This type of paver is used widely in building and landscaping as it is highly prized for beauty, strength and durability. Stone pavers are made of many materials including limestone, bluestone, basalt (such as that from The Palisades used in New York City), sandstone and granite. Travertine is a durable, low-porous stone that stays cool in direct sunlight, making it a popular choice for pool-sides, patios, walkways and outdoor entertainment areas. Travertine is salt tolerant and has a low sunlight reflection. Granite pavers have high integral strength and density making it easy to maintain and hard-wearing in outdoor use. Limestone pavers are cut from natural limestone blocks, a sedimentary rock found in mountainous areas and ocean sea beds. Limestone tends to have unique natural colour variations. Sandstone pavers are derived from natural stone and tend to be used for sidewalks, patios and backyards. Pavement and urban environment Impermeable asphalt and concrete pavements prevent water from passing into the ground. This creates excess runoff that can worsen flooding, especially in heavily-paved urban areas. Permeable pavers can be used to prevent excess runoff, but have lower compressive strength, ravelling, segregation and difficulty in compaction. See also Macadam Permeable paving Hoggin References External links Building materials Concrete Floors Garden features