Vaulted sidewalks, also called sidewalk vaults and areaways are

sidewalk A sidewalk (North American English), pavement (British English, South African English), or footpath (Hiberno-English, Irish English, Indian English, Australian English, New Zealand English) is a path along the side of a road. Usually constr ...

s that are not placed directly on the ground. Rather, there is an empty space below them where the ground level used to be. This may happen where the street level has been raised over time, or where basements are extended, or as

utility vault A utility vault is an underground room providing access to subterranean public utility equipment, such as valves for water or natural gas pipes, or switchgear for electrical or telecommunications equipment. A vault is often accessible directly fr ...

s. Sidewalk vaults may be protected as historical architecture, or filling them required for planning permission.

Chicago

The

raising of Chicago During the 1850s and 1860s, engineers carried out a piecemeal raising of the grade of central Chicago to lift the city out of its low-lying swampy ground. Buildings and sidewalks were physically raised on jackscrews. The work was funded by privat ...

started in 1855 as a response to the muddy conditions of the streets and because of epidemics of cholera. The raised streets needed new, raised sidewalks to match them. In the case of vaulted sidewalks, which might be 5 feet (1.5 m) or more over the original street level, a structure was built to hold a new sidewalk at the new street level, and an empty space was left between the original and the new sidewalks. This process gave building owners a choice: raise their buildings to the new street level, or relocate the main entrance to the second floor of the building to match the new street level. Many buildings chose the latter option, opting to use the vaulted area for storage. As recently as 2001 there were still over 2,000 vaulted sidewalks in Chicago Today the old vaulted sidewalks are visible mostly during construction and cause increased costs of

infrastructure Infrastructure is the set of facilities and systems that serve a country, city, or other area, and encompasses the services and facilities necessary for its economy, households and firms to function. Infrastructure is composed of public and pri ...

maintenance. Vaulted sidewalk in Chicago

Milwaukee

, several sidewalk vaults, or "hollow walks," remain in Milwaukee's Historic Third Ward and increase the cost of street and sidewalk reconstruction.

New York

In New York, basements may extend beneath the sidewalk and drivers are warned "HOLLOW SIDEWALK, DO NOT PARK".

Seattle

Some

Seattle Underground The Seattle Underground is a network of underground passageways and basements in the Pioneer Square, Seattle, Pioneer Square neighborhood of Seattle, Washington, United States. They were located at ground level when the city was built in the m ...

sidewalks have

vault light Pavement lights (UK), vault lights (US), floor lights, or sidewalk prisms are flat-topped walk-on skylights, usually set into pavement (sidewalks) or floors to let sunlight into the space below. They often use anidolic lighting prisms to throw t ...

s, inset glass that trasmits sunlight to the lower level.

Use for daylighting

Prism lighting Prism lighting is the use of prisms to improve the distribution of light in a space. It is usually used to distribute daylight, and is a form of anidolic lighting. Prism lighting was popular from its introduction in the 1890s through to the 1930 ...

allows sidewalk vaults to provide daylight to the basement. File:Lucidux daylighting.gif, alt=Diagram of prisms in a pavement bending light to hit a wall of glass prims lying directly under and in line with the basement wall, which bend the light further to the horizontal, Two-stage refraction system for basement lighting; prism wall below center, shop above left. Note

I-beam An I-beam is any of various structural members with an - (serif capital letter 'I') or H-shaped cross section (geometry), cross-section. Technical terms for similar items include H-beam, I-profile, universal column (UC), w-beam (for "wide flang ...

and

masonry wall Masonry is the craft of building a structure with brick, stone, or similar material, including mortar plastering which are often laid in, bound, and pasted together by mortar (masonry), mortar. The term ''masonry'' can also refer to the buildin ...

. File:Prism salesroom.gif, alt=A brightly-lit room with the inside edge lined with carrell desks. The ceiling is made of pendant prisms, supported by a very unobtrusive frame (which is in turn supported at wide intervals by slender diagonal braces from the walls). The wall over the desks is made of prism tiles., The same system used to light a salesroom inside a hollow sidewalk; prism wall is on the right,

s above. File:Daylit basement 112 state st.jpg, alt=A black-and-white photo of an unfurnished basement, horizontally lit with diffuse light. It has a pale coffered ceiling, with thickish round pillars supporting the intersections of the beams. The lower half of both pillars and walls is covered with dark wood panelling. The bare floor is pale grey., A basement daylit by sidewalk prisms (prisms out-of-shot to the left)

References

Vaulted sidewalk in front of a store in Chicago

{{reflist Pavements Sidewalks