page_title: Grid plan
section_title: Financial cost
hierarchical_section_title: Grid plan / Benefits and criticisms / Financial cost
caption_attribution_description: Unusually-numbered street sign in Patterson Township, Beaver County, Pennsylvania, United States.
context_page_description: The grid plan, grid street plan, or gridiron plan is a type of city plan in which streets run at right angles to each other, forming a grid. The infrastructure cost for regular grid patterns is generally higher than for patterns with discontinuous streets.
  Costs for streets depend largely on four variables: street width, street length, block width and pavement width. Two inherent characteristics of the grid plan, frequent intersections and orthogonal geometry, facilitate pedestrian movement. The geometry helps with orientation and wayfinding and its frequent intersections with the choice and directness of route to desired destinations.
  In ancient Rome, the grid plan method of land measurement was called centuriation. The grid plan dates from antiquity and originated in multiple cultures; some of the earliest planned cities were built using grid plans.
context_section_description: Street width, or right of way (ROW), influences the amount of land that is devoted to streets, which becomes unavailable for development and therefore represents an opportunity cost. The wider the street, the higher the opportunity cost. Street width is determined by circulation and aesthetic considerations and is not dependent on the pattern configuration. Any configuration can have wide or narrow streets.
  Street length influences proportionately the amount of street components that have to be constructed such as pavement, curbs and sidewalks, storm sewers and drains, light poles, and trees. The street length of a given area of development depends on the frequency at which streets occur which in turn depends on the length and width of a block. The higher the frequency of streets the longer is their total length. The smaller the block dimensions the higher the frequency of the streets. As the frequency of street increases so does the number of intersections. Intersections normally cost more than straight street length because they are labour-intensive and require street and traffic signage.
  Pavement width influences the cost by affecting the amount of materials and labour required to provide a finished road surface. Pavement width is generally based on traffic engineering considerations and is not dependent on pattern configuration. As with the street width, any pattern can have wide or narrow pavements.
  Of all three factors that affect cost, street width, street length and pavement width, only street length is pattern dependent. An objective cost comparison would, therefore, rely on this variable with the full understanding that the other variables, though optional, can play a role.
  Traditional orthogonal grid patterns generally have greater street frequencies than discontinuous patterns. For example, Portland's block is 200 feet × 200 feet while Miletus' is half that size and Timgad's half again (see diagram). Houston, Sacramento and Barcelona are progressively bigger reaching up to four times the area of Portland's block. New York's 1811 plan (see above) has blocks of 200 feet (61 m). in width and variable lengths ranging from about 500 to 900 feet. The corresponding frequency of streets for each of these block sizes affects the street length.
  A simple example of a grid street pattern (see diagram) illustrates the progressive reduction in total street length (the sum of all individual street lengths) and the corresponding increase in block length. For a corresponding reduction of one, two, three and four streets within this 40-acre (16 ha) parcel, the street length is reduced from an original total of 12,600 to 7,680 linear feet, a 39% reduction. Simultaneously, block lengths increase from 200 × 200 feet to 1240 × 200 feet. When all five blocks have reached the ultimate size of 1,240 feet (380 m) four street lengths out of total eight have been eliminated. Block lengths of 1000 feet or larger rarely appear in grid plans and are not recommended as they hinder pedestrian movement (Pedestrianism, below). From the pedestrian perspective, the smaller the block is, the easier the navigation and the more direct the route. Consequently, the finer grids are preferred.
  Patterns that incorporate discontinuous street types such as crescents and culs-de-sac have not, in general, regarded pedestrian movement as a priority and, consequently, have produced blocks that are usually in the 1000-foot range and often exceed it. As a result, street frequency drops and so does the total street length and, therefore, the cost. In general, it is not the street pattern per se that affects costs but the frequency of streets that it either necessitates or purposely incorporates.
  An inherent advantage of the orthogonal geometry of a proper grid is its tendency to yield regular lots in well-packed sequences. This maximizes the use of the land of the block; it does not, however, affect street frequency. Any frequency of orthogonal streets produces the same packing effect. Orthogonal geometry also minimizes disputes over lot boundaries and maximizes
caption: In a numbered grid system, adding an extra street can cause confusion
exif: {"Image ImageDescription": "IM000027.JPG", "Image Make": "Hewlett-Packard", "Image Model": "Photosmart M407", "Image Orientation": "Horizontal (normal)", "Image XResolution": "72", "Image YResolution": "72", "Image ResolutionUnit": "Pixels/Inch", "Image Software": "1.02_O", "Image DateTime": "2005:09:25 13:00:54", "Image YCbCrPositioning": "Co-sited", "Image Copyright": "Copyright 2003-2004", "Image ExifOffset": "3808", "Image DigitalZoomRatio": "1", "Image SceneCaptureType": "Standard", "Image GainControl": "223", "Image Contrast": "Normal", "Image Saturation": "Normal", "Image Sharpness": "Hard", "Image SubjectDistanceRange": "3", "Image Tag 0xA421": "5", "Image Tag 0xA422": "[513, 12, 0, 0, 1045, 1050, 1055, 1062]", "Image Tag 0xA423": "b'\\x15\\x04\\x1a\\x04\\x1f\\x04&\\x04-\\x045\\x04=\\x04F\\x04N\\x04V\\x04, ... ]", "Image Tag 0xA424": "e", "Image Tag 0xA425": "[978, 712, 11600, 11852, 947, 871, 138, 0, 1, 1, 41, 0]", "Image Tag 0xA426": "[138, 0, 1, 1, 41, 0, 65, 88, 7, 131, 10, 1, 1, 9999, 0, 0, 0, 0, 0, 0, ... ]", "Image Tag 0xA427": "[]", "Image Tag 0xA428": "[]", "Image Tag 0xA429": "[131, 123, 0, 0, 62392, 2537, 192, 105]", "Image Tag 0xA42A": "1", "Image Tag 0xA42B": "0", "Image Tag 0xA42C": "513", "Image Tag 0xA42D": "12", "Image Tag 0xA42E": "[]", "Image Tag 0xA42F": "2", "Thumbnail Compression": "JPEG (old-style)", "Thumbnail XResolution": "0/0", "Thumbnail YResolution": "65560/0", "Thumbnail ResolutionUnit": "Pixels/Inch", "Thumbnail JPEGInterchangeFormat": "4312", "Thumbnail JPEGInterchangeFormatLength": "5072", "EXIF ExposureTime": "1/512", "EXIF FNumber": "481/100", "EXIF ExposureProgram": "Program Normal", "EXIF ISOSpeedRatings": "100", "EXIF ExifVersion": "0220", "EXIF DateTimeOriginal": "2005:09:25 13:00:54", "EXIF DateTimeDigitized": "2005:09:25 13:00:54", "EXIF ComponentsConfiguration": "YCbCr", "EXIF CompressedBitsPerPixel": "21871/12000", "EXIF ShutterSpeedValue": "9", "EXIF ApertureValue": "1133/250", "EXIF ExposureBiasValue": "0", "EXIF MaxApertureValue": "1541/500", "EXIF SubjectDistance": "48/25", "EXIF MeteringMode": "Average", "EXIF LightSource": "Unknown", "EXIF Flash": "Flash did not fire, auto mode", "EXIF FocalLength": "25/4", "EXIF FlashPixVersion": "0100", "EXIF ColorSpace": "sRGB", "EXIF ExifImageWidth": "1600", "EXIF ExifImageLength": "1200"}