11 Diagonal Street (also known as the diamond building) is an iconic office tower in downtown

Johannesburg Johannesburg ( , , ; Zulu language, Zulu and Xhosa language, Xhosa: eGoli ) (colloquially known as Jozi, Joburg, Jo'burg or "The City of Gold") is the most populous city in South Africa. With 5,538,596 people in the City of Johannesburg alon ...

South Africa South Africa, officially the Republic of South Africa (RSA), is the Southern Africa, southernmost country in Africa. Its Provinces of South Africa, nine provinces are bounded to the south by of coastline that stretches along the Atlantic O ...

, that was built by Anglo American Property Services. The 22 floor building is the 15th tallest in the city and it was conceptualized in 1981 and excavations began in December that year. Construction ended in 1983 and the building was tenanted in 1984. The building is designed to look like a

diamond Diamond is a Allotropes of carbon, solid form of the element carbon with its atoms arranged in a crystal structure called diamond cubic. Diamond is tasteless, odourless, strong, brittle solid, colourless in pure form, a poor conductor of e ...

as it reflects different views of the

Central Business District A central business district (CBD) is the Commerce, commercial and business center of a city. It contains commercial space and offices, and in larger cities will often be described as a financial district. Geographically, it often coincides wit ...

from each angle of the building. Apart from its unique exterior, the structure was built with concrete instead of steel, demonstrating that concrete could be used instead of steel in both speed and cost. The building's architect was

Helmut Jahn Helmut Jahn (January 4, 1940 – May 8, 2021) was a German-American architect, known for projects such as the Sony Center on Potsdamer Platz in Berlin, Germany; the Messeturm in Frankfurt, Germany; the Thompson Center in Chicago; One Libert ...

and is featured on the Level 42 album cover The Very Best of Level 42.

Current Use

The building was used by the department of Development Planning & Local Government. It is currently occupied by The Gauteng Department of Infrastructure Development.

References

Office buildings completed in 1984 Skyscraper office buildings in Johannesburg Helmut Jahn buildings 20th-century architecture in South Africa Buildings and structures in Johannesburg {{SouthAfrica-struct-stub