Dallas City Hall is one of the finest buildings designed by architect I.M.Pei. The structure is located at the Dallas city center and stands as a strong architectural statement. The building was constructed in 1977 extending over a site area of 11.8 acres. It has graciously stood the test of time for over 40 years and won many awards of excellence. I.M.Pei wanted the city hall to be a reflection of its people. v
In the words of I.M.Pei, “When you do a city hall, it has to convey an image of the people, and this has to represent the people of Dallas … The people I met – rich and poor, powerful and not so powerful – were all very proud of their city. They felt that Dallas was the greatest city there was, and I could not disappoint them.” The design of Dallas City Hall showcases his understanding of user psychology and their emotional connection with the building.
As a public building, it’s architectural gesture was required to be welcoming and interactive. The ideation sketch was initiated by scribbling out an inverted pyramid form. The present form of the building is said to have its inspiration from this concept. Pei recognized that the building had to welcome the public, so he concentrated offices and counters where the public came to conduct its business at ground level. This suggested a small space at the bottom of the building, with increasing floor space higher up to house the offices that ran the government. As he began to play with sketches, the inverted pyramid profile took shape.
The building is inclined at an angle of 34 degrees. Being a public building, it was designed to resonate and have a dialogue with the masses and hence the angulation. It was inclined to allow more interaction along the growing downtown area to the north of the site. Pei persuaded the city to acquire an additional six acres (2.4 hectares) in front of the building which is equivalent to two full city blocks as a plaza and use it as an appreciation space for the building. It’s inclined form is extensive and accommodates diverse programmatic functions, rustic and powerful style of designing. The building is 560 feet long and each floor is about 9 feet wider than the floor below.
The building houses 17800 sq.ft of office space, 25,000 sq. ft of Great Court, 5,000 sq.ft of reception lobby, 250 seat capacity for the Council chamber, 4.7 acre Plaza with 180 feet diameter of the swimming pool, monumental sculpture, three 84’ high conical flagpoles, 2-level underground disaster shelter and 1325 car capacity garage. The first and second floor of the building accommodates Public facilities, Action Centre, Water Utility Bureau and Consumer Affairs.
The building design has an inside-out approach. It is a combination of a building and a park. Being situated in the city center contributes to the much needed open space in the city. The building form has both functional and symbolic logic. Considering the building surroundings, it serves as a catalyst for future development. It is designed as a horizontal expanse which is contradictory to high-risers in its vicinity.
The longevity of the building looks massive yet looks well distributed between the three bulky columns. The cylindrical pillars appear to hold up the structure. They are functionally stairwells that had originally been concealed within the design but were brought forward to lend visual support. However, they do not technically bear the load of the building.
The cantilevered floors are supported by 14 large bearing walls. The wall section is 18 inches (46 centimeters) thick, arranged in seven pairs. The pairs describe a width of 14 feet (4.3 meters), except in cases where they flank the staircase towers. 11-foot wide areas enclosed by the pairs are used to house mechanical and electrical services. In between the pairs are 65′-4″ spans of office space.
Pei wanted the building to feel like an organic product of the region. Therefore he was inclined to use a buff-colored concrete for construction and finishings because it resembled the local earth tones. The structure is built as a cast-in-place for interiors and exteriors. Concrete gives the impression of a raw and sturdy structural form.
Research and case studies were undertaken to understand concrete both aesthetically and structurally. The design team toured the site and its vicinity to observe large concrete cast-in-place buildings and paid attention to it’s cracking characteristics. Based on this study, different aggregates and mix designs were tested, casting more than 50 sample panels following which the feasible design was evolved.
The structure exploited to its best, the use and care of the concrete. The material was extensively used as an expression of truth to its origin. It was Pei’s outlet to represent transparency and purity at the core of the city. Concrete gave the building a bulky yet subtle look of truthfulness.
Visual symmetry was a vital feature of the design. The building form used the repetition of structural elements as a way of making a demanding design more affordable. Coffered ceilings were formed on fiberglass domes which could be reused numerous times without deterioration.
In totality, the Dallas City Hall serves as an example of minimalist design. It expresses the grandeur and pride of its citizens in the most subtle yet effective way.