This was a short story and would have been about the early to mid-60s.

A committee of men has gathered to discuss the recent (2 weeks ago?) spontaneous collapse of a skyscraper. One of the men is soon established to be a dim, upper-class twit with nothing to contribute. That a skyscraper could simply collapse (literally fell over, in fact) is unprecedented, and the committee is stumped. The implications are unnerving.

Near the end of the story the twit reveals that he had had a narrow escape, since he lived in the penthouse suite (an entire floor) of the collapsed building, and had been in Europe on vacation when the collapse occurred. And he insists on telling the others that his wife accuses him of leaving the bath running when he left.

The others realize that, since the apartment was sealed, the entire floor would have filled with water and caused the collapse due to its weight.