Brian Resnick, at Mashable writes:

The social events of the 1948 holiday season had to be canceled. And with good reason: Experts called the third floor of the White House “an outstanding example of a firetrap.” The result of a federally commissioned report found the mansion’s plumbing “makeshift and unsanitary,” while “the structural deterioration was] in ‘appalling degree,’ and threatening complete collapse.” The congressional commission on the matter was considering the option of abandoning the structure altogether in favor of a built-from-scratch mansion, but President Truman lobbied for the restoration. [Please click through the link to check out the pictures. They're worth it. I wouldn't ever link to Mashable, otherwise.