A public utility building (also known as infrastructure building, and utility building) is a building used by a public utility to maintain its office or to house equipment used in connection to the public utility. Examples include pumping stations, gas regulation stations, and other buildings that house infrastructure components and equipment of water purification systems, water distribution networks, sewage treatment systems, electric power distribution, district heating, telephone exchanges, and public service telecommunication equipment.

After the Industrial Revolution, cities in the industrialized countries required to construct and maintain infrastructure facilities to support city growths. Modern water industry was one of the early types of city infrastructure that was born in the early 19th century out of that necessity. There were three types of structures that were unique to the water industry: pumping stations (including water and wastewater), water towers, and dams. In particular, the pumping stations that housed large steam engines in the 19th and early 20th centuries were built intentionally to be symbolic. The building architectures were to communicate a message to the public of safety and reliability, and express their functions. Building designs inherited from beam engine buildings required strong rigid walls and raised floor to support the engines, large arched and multi-story windows to let the light in without compromising wall strength, and roof ventilation such as decorative dormers. These functional features formed the principal of "waterworks style." An example of simple waterworks architectural style is Springhead Pumping Station. More elaborated designs were also used to communicate sacred atmosphere to highlight the importance of critical tasks of the facilities such as in sewage pumping stations. An example is Abbey Mills Pumping Station that employed baroque eclecticism in its design.

The city infrastructure buildings in this period were more communicative and expressive with their own designs without having to conceal their locations from the public. However, the internal machinery is not exposed to the view from public streets as the buildings provide a decorative "cloak" function. Other examples are Radialsystem (Berlin, Germany sewage pumping station), Kempton Park engine house, Chestnut Hill Waterworks in Massachusetts, United States, Spotswood Pumping Station in Melbourne, Australia, Palacio de Aguas Corrientes in Buenos Aires, Argentina, Sewage Plant in Bubeneč, in Prague, Czech Republic, and R. C. Harris Water Treatment Plant in Toronto, Canada. These buildings are considered to be part of the world heritage in the water industry.

Other types of infrastructure facilities had their unique architectural expressions as well. Those include gas supply, electrical supply and communication buildings. An example for electrical substations is seen in a 1931 Commonwealth Edison substation at 115 North Dearborn Street in Chicago. The building completely encloses the equipment but the facade is decorated with a basrelief in Art Deco style. In New York City, many substations built in the 1920s and 1930s to power its subway system incorporated Art Deco ornamental features. These included diamond patterned brickwork, zigzag motifs, limestone carving of Art Deco lettering, and other incised relief designs.

Since the postwar period in the second half of the twentieth century, infrastructure buildings were constructed in utilitarian style. Infrastructure projects including public utility buildings fall within the responsibilities of civil engineers, typically without participation of architects. As a result, the builders of those structures prioritize functional aspects of the buildings without having attention on detailing or ornamentation beyond what are necessary for the functions of the buildings.

Many of these public utility buildings need to be close to the users. They may need to be in residential and commercial areas of the cities in which the public has an expectation of the areas to be aesthetically pleasing to attract residents and visitors. One strategy to hide unattractive equipment is to create enclosures or buildings with exterior designs to disguise and blend in to the neighboring buildings. The goal is to make the buildings not to stand out so that they can stay anonymous. In some municipalities, this design decision is mandatory. For example, public utility buildings in residential zones of Montgomery County, Maryland are required to have exterior appearance of residential buildings.

Large scale implementations of this design strategy can be seen in Toronto and Washington, DC where the electric operators put electrical substations in buildings that are disguised as houses in the neighborhoods (also known as fake houses).

Another example is the 23-story AT&T equipment building at 10 South Canal Street in Chicago. While the ground floor and the top floors have an appearance of a normal skyscraper, the middle 18 floors of the building are windowless concrete to protect the equipment. The architect designed rough-grooved concrete texture to disguise as windows of typical office buildings.