As it was already mentioned, there are four main factors which led to the rise of granny flats. But how exactly can having one help you? If we’re talking about multi-generational living, besides offering your adult children, or elderly relatives an affordable place to live, you also have them close. To exemplify, in Sydney, granny flat builders in Castle Hill can build  a 60-square-meter granny flat, with two bedrooms, and a bathroom.