Throughout "Zooey," Bessie worries about getting Franny out of the living room so the painters can get in there to do the walls. The entire apartment is being repainted – in other words, change is in the air in the Glass house. Remember that Franny undergoes a significant transformation at the end of the novel; it's fitting, then, that the physical setting is transformed along with her.
Early in the story, we worry that Franny won't be able to resolve her crisis, that she, like the walls of her apartment, just isn't prepared. ("The Glasses' living room was about as unready to have its walls repainted as a room can be" (Zooey.6.1).) But by the end of the text, we find that both Franny and the walls have been "repainted," in one way or another:
Although there was nothing markedly peculiar about her gait as she moved through the hall […] she was nonetheless very peculiarly transformed as she moved. She appeared, vividly, to grow younger with each step. Possibly long halls, […] plus the smell of fresh paint, plus newspapers underfoot – possibly the sum of all these things was equal, for her, to a new doll carriage. In any case, by the time she reached her parents' bedroom door her handsome tailored tie-silk dressing gown – the emblem, perhaps, of all that is dormitorially chic and fatale – looked as if it had been changed into a small child's woolen bathrobe. (Zooey.8.6)