Aerial picture of my neighborbhood in San Martin, Buenos Aires
I've grown up in an immigrants neighborhood in Gran Buenos Aires, it means outside Downtown. My immigrants neighbours were mostly Italian, then Yugoslavian and Spanish. Though my father's friends were mostly first generation of Italians, he used to complain saying that the neighborhood did not grow, because of the Italian habits. For a Spanish thinker, the houses MUST grow high, in a second floor. And he struggled long years to finalize the construction of a two stories house. What we never discussed is that Italians made adjacent additions to the back of the properties, as the families were arranged one next to the other. See I say " arranged" because it was like a family obligation. For Yugoslavian, it was one in front of the other, or pretty close, for Spanish, pretty close, let's say a couple of blocks away. Maybe what he meant was that the neighborhood never changed its physiognomy, unless you see it in an aerial picture. As we can see in the picture, lots are covered as much as possible, except for my parent's house (look at the center with the trees), that keeps a great part of the lot for landscape and vegetables cultivation.
My conclusion is that immigrants neighborhoods grow per the majority of inhabitants' needs, which are based on their culture and identity.