As President Harry Truman’s daughter, Margaret, played the piano one day, she was startled as one leg of the piano suddenly dropped through the floor of the White House residential level. Engineers were called in to see what was going on, and the report was nothing short of alarming.

The 150-year-old mansion was in desperate need of help. Over the past century and a half much had been done to the building with little regard for the structural mainenance or integrity. One engineer summed up his findings for the President by telling him that the White House was standing up “merely from force of habit.”

The First Family could not safely remain any longer. They moved across the street to the Blair House while the White House received an extreme makeover. The simplest approach would have been to level the entire building and start all over again. President Truman had a keen appreciation for history and for the symbolic importance of the building, however, and he insisted that the outer walls must remain. Everything else was fair game.

From 1948 to 1952 the White House was off limits to all but construction workers as the entire interior was removed, leaving only the outer walls as shell. Wooden beams were replaced with steel, and modern plumbing, electrical, and communications systems were installed.

Throughout this process the President kept himself fully informed and involved. When the need arose to bring a bulldozer and truck inside the structure, workers proposed knocking a hole in the wall so the equipment could enter. Truman refused, and required the workers to disassemble the equipment, bring it inside in pieces, and reassemble it there.

One addition the President particularly wanted was a balcony to adorn the South Portico. While the cost was approved by Congress, one unexpected expense came up when it was observed that the back of the $20 bill would need to be re-engraved to account for the architectural improvement.