How are narrative conventions used to represent attitudes?

Narrative conventions are the techniques employed by a writer to lend meaning to a story. They can include everything from point of view, imagery used, form, characterization, and so on.
The point of view in this story is an interesting one. By necessity, the narrator is an omniscient, disembodied one: it seems to watch the house as if watching it from a distance on a television screen, watching even though there are no people left to see. Phrases such as "dawn showed faintly" raise the question of who dawn is showing itself to; likewise, things "could be seen" and "could be heard," but what resonates with the reader is the question: by whom?
Bradbury answers that story, to an extent, in the way he chooses to characterize the house and the things in it. In the absence of people, the house has almost become a living thing itself. It has human attributes; it "shuddered," has "nerves," and when it begins to fall apart in the heat of the fire, it is described as being "revealed as if a surgeon had torn the skin off." This simile enforces the personification which Bradbury utilizes throughout the story: there is a sense that the house, having been filled with "voices" by the humans who once lived in it, has now gone beyond the point of being a created thing, and become sentient. It cries for "help," it "[tries] to save itself," but to no avail. Like the humans who are absent from this world, it must ultimately perish.
The characterization of fire, too, is one of personification. Fire "fed" and "crackled," "lay in beds, stood in windows, changed the colors of drapes!" In the absence of humans, this most elemental of things literally takes their place. The metaphors Bradbury uses here enforce the idea that fire can consume anything humans have created; it has its own motivations, too, and will outlast anything man made. At the end of the story, fire has consumed everything but the one "last voice" still announcing the date.
There is significance, too, in the date being the last thing said in the story. While the house may have been disintegrated, a new "dawn" has still risen, and the sun is still shining on the house that is no longer there. "Today is August 5, 2026," and the dawn shows whether or not there is anything there to see it. The closing paragraphs of the story serve as a reminder that the world will continue to turn and new days will continue to come, whether or not there are humans here to witness it.