Buildings often outlive their function; however, their inherent durability often gives the building another life. There is a long tradition of buildings being adapted to suit new functions. Roman basilicas were converted to serve as worship spaces for the nascent Christian church. In medieval times, Roman fortifications were resurrected to form part of the fabric of the mercantile cities. It was not until the advent of ready demolition and the mechanization of the building process during the Industrial Revolution that the practice of adapting old buildings to new uses became less the norm.

Following World War II, the pace of change in urban form, precipitated by technological advances and social upheavals, quickened. As buildings became obsolete and shifting land values directed economic development away from central cities, particularly in North America, large-scale demolition became commonplace. In some cases, well-built warehouses and industrial structures stood on land that had become more valuable for other commercial and office uses, further accelerating demolition. Housing that stood in the pathway of proposed highways was also torn down. Urban renewal stopped short of its promise, and vacant buildings quickly became vacant land. To combat these failures, preservation strategies were developed that employed the existing built environment to suit new uses.

There are four distinct building types in which adaptive re-use of older structures can be seen. Public buildings, which includes large transportation facilities like train stations and civic buildings built in the 19th and 20th centuries being converted to new public and private uses. Industrial buildings, with their large clear structural spans and, typically, large expanses of windows or skylight, lend themselves particularly well to housing an enormous variety of new use groups. Private buildings, like large houses, can serve multiple functions because of the inherent flexibility of the prototype. Finally, commercial buildings, the structures that are so emblematic of the advances in architectural technology in the 20th century, are being recycled with different uses, presenting unique preservation problems, as architects must address issues related to preserving buildings that employed contemporary technology.

The U.S. government owns many magnificent historic structures and has taken the lead in finding new uses for its stock of buildings, serving as an example for private sector development. In Washington, D.C., the Pension Building, an imposing brick edifice, was constructed shortly after the Civil War to provide office space for agencies distributing pensions to war veterans and their families. Its primary distinctive feature is a large, central skylit atrium space that allows the ring of offices access to natural light. The building stood dormant for many years until a major restoration project started in 1984 enabled the National Building Museum to occupy the lower floors of the building, with the bulk of the building retained for government offices. The soaring splendor of the building’s interior serves as an excellent advertisement of its function as a museum for the built environment.

Also in Washington, D.C., is the Old Post Office Building, another atrium building. Completed in 1899, the neoRomanesque building was almost demolished in the early 1970s. Fortunately, as a result of the dedicated efforts of local preservationists and the daunting cost of demolishing such a huge structure, the building was renovated in 1978. The three lower levels of the building, including the atrium, were converted to restaurants and retail, with the perimeter of the building on the upper level retained as office space. One of the most well-known re-uses of a dormant train station is Gae Aulenti’s remaking of the Gare d’Orsay in Paris as the national museum of art and civilization. Originally opened for train traffic in 1900, both the building’s short platform lengths and changes in travel patterns lead to the abandonment of the station shortly after World War II. Reopened as a museum in 1986, the renovation makes use of the original attached hotel within the head house as exhibition space. Built within the volume of the train shed are smaller structures that house more intimate display space for sculpture. Despite the somewhat awkward intrusion of these galleries within the shed, the sense of the original great volume of the space is still preserved.

In the United States, the nation’s private railroad system developed a legacy of magnificent structures throughout the country. When train traffic declined following World War II, these buildings, centrally located in the downtowns of virtually every American city, sometimes were virtually abandoned or, worse, torn down in the case of McKim, Mead and White’s Pennsylvania Station in New York. Union Station in St. Louis (Theodore C.Link), built in 1894 and renovated and modified in the early 1980s, is a good example of an important building restored to a new life. The barrel-vaulted Grand Hall functions in much the same way as it was originally intended, now serving as a hotel lobby and entrance to a multiuse complex that includes a parking garage and a restaurant and retail center within the former train shed. The shed, the largest of its type ever built, is organized into “neighborhoods” to make the integration of the building’s multiple functions more coherent. When Union Station was renovated, the ornate and eclectic spaces within the head house were restored and glass was inserted into the vaulted train shed, flooding the interior with natural light.

In Philadelphia, a large commuter train station built for the Reading Railroad in 1893 became redundant in 1984 when a subterranean tunnel was constructed below it, linking the area’s railways to a regional network. The beautiful steel and glassvaulted shed and Renaissance revival terra-cotta facade were empty for several years as several different alternatives were studied for a possible re-use. Critical to the success of the project was the maintenance of the historic food market below the train shed. The Pennsylvania Convention Center, built in 1992 (Thompson, Ventulett, Stainback and Association), incorporates the Reading Terminal into the new construction, maintaining both this vital piece of urban architecture and the market’s social importance in the city fabric. The head house serves as the ceremonial entrance for the convention center as well as a hotel. The train shed links the entrance from the principal street to the new large convention center that spans over two adjacent blocks.

The first International Style skyscraper, the PSFS Building (George Howe and William Lescaze), also in Philadelphia, was constructed in 1932 and served for many years as the headquarters for a local bank and office building. The building had retail on the ground floor with a cool modern banking hall on the second floor. After the bank went out of business in the early 1990s, the building stayed dormant for many years. Despite the high esteem held for the building locally, its relatively small floor plate did not attract the interest of businesses seeking space where the need for a large flor negated the desire to have ready access for natural light. Fortunately for the building, developers converted it to a hotel that uses the original banking hall as a multipurpose room. The former retail space now serves as a ground floor lobby and restaurant. The renovation is truly successful and the building retains its landmark neon sign, first lit to advertise the bank during the depths of the Depression.