There is not such a sharp contrast between the interior of the house and the occurrences of the outside in Bradbury's story. For, in both locations mankind has destroyed mankind. Apparently, there is order as the house is so technologically advanced that it runs itself, but man's technology has dehumanized him as there no longer are the human acts of communication and routine. No letters are written, no conversations are made, no quotidian tasks are performed such as sweeping, washing, and cooking the meals.
While the main irony of "There Will Come Soft Rains" lies in the fact that man's technology, created to make his life easier, has actually destroyed humans--"the time is out of joint" as Hamlet says. Moreover, Nature does not care if mankind perishes, as Sara Teasdale expresses in her poem,
Not one would mind, neither bird nor tree
If mankind perished utterly;
And Spring herself, when she woke at dawn
Would scarcely know that we were gone
Outside, against the west [the direction symbolic of death] wall of the house there appears to be silhouettes of the residents of the house:
The five spots of paint--the man, the woman, the children, the ball--remained. The rest was a thin charcoaled layer.
Chaos has occurred in the form of a nuclear blast and the lives of the residents of the house have been destroyed outside the house. And, yet, the technology inside the house that has dehumanized these residents has destroyed them spiritually, already.