I. M. Pei Building facts for kids

The I. M. Pei Building, also known as the Wilmington Tower, is a tall office building in Wilmington, Delaware. It stands as the third tallest building in Delaware. This building is special because it's the only one in the state designed by the famous architect I. M. Pei. It was finished in 1971 and is about 282 feet (86 m) tall, with 23 floors.

Building's Story

How the Building Began

The idea for this building started in 1964. The American Life Insurance Company (ALICO) announced plans to build it. People in Wilmington were very excited about the design. A local writer even said they would be as proud of it as they were of historic places like Old Swedes Church.

Construction started in 1966. It was supposed to be ready by 1968. However, the project took longer than planned. There weren't enough workers, the weather caused delays, and I. M. Pei had very high standards. The building was finally completed in 1971. It cost more than the original budget, but the exact final price isn't known.

Challenges and Changes

When the building officially opened as the Wilmington Tower in 1970, it faced money problems. Several other office buildings had been built while it was under construction. This meant there was a lot of competition for office space. The building's high rental prices were not attractive to businesses.

By 1972, only one year after it was finished, the building had just two tenants. It stayed more than half empty through the 1980s. People who worked there reported issues like broken elevators, poor heating and cooling, and even leaks.

In 2004, the owners announced a big renovation project. They planned to spend $6 million to fix many of the problems. They also wanted to change how the building looked. However, architects and people who care about old buildings didn't like the planned changes. After hearing their concerns, most of the controversial changes were stopped. The renovations were finished in December 2004. These improvements helped more businesses want to rent space in the building right away.

Building's Design

Inside the Building

The I. M. Pei Building is made from cast in place concrete. It has 20 floors for offices. There are also two floors for building machinery. The ground floor is extra tall. Each office floor is about 66 feet (20 m) wide and 75 feet (23 m) long. This gives about 4,440 square feet (412 m²) of usable space on each floor. This size is considered small for a modern office building.

To make the office floors completely open, Pei put the building's services, elevators, and stairwells on the outside. These are in two special sections called "cores." He used strong post-tensioned beams to hold up the floors. These beams run parallel to the longer side of the building. This was a harder way to build, but it meant there were no columns inside the office space. Before walls were added, you could see all the way through the narrow building.

Outside the Building

The building's style is called Brutalism. This style uses lots of raw concrete and strong, blocky shapes. I. M. Pei used similar ideas in other buildings he designed around the same time. Examples include the Green Building and Society Hill Towers.

Pei made the building look slender on the Market Street side. This was to make sure it didn't look too big next to older, smaller buildings nearby. One of these is the historic Wilmington Club. The north and south sides of the building have large windows. These windows are separated by concrete beams with special grooves. A very similar design was later used by Pei's partner, Henry N. Cobb, on the Baltimore World Trade Center. The east and west sides of the building have no windows. These sides are where the supporting cores are located.