The home of the late Edith Macefield is best known for withstanding the encroaching development of the area, especially when Macefield refused an offer of a million dollars from those developing around her. Even without the balloons, that seems like an ideal complement to the stance the film's protagonist takes before taking off.
I can't help but wonder, though, if the winds weren't perhaps strengthened by the narrow space now surrounding the home... the winds of change, that is! Oh, never mind all that. That's one perfectly adorable house, and Up's one perfectly adorable movie.
(Thanks to Sarah for passing this on.)