A large body of research has been focused on the various social, environmental and economic impact that urban density might incur for cities. However, there is less consistency between the measurements that these studies usually apply to address density. This results in contradictory and divided outcomes and discards some of the influential factors, such as the design of the built form. This paper emphasises that the same building density can yield into different design layouts, and thus, needs other measurements to be defined. Therefore, several cases with various ranges of density (low, medium, and high) have been explored through spatial analysis and then have been categorised in 3 clusters to further study with statistical tests, i.e. ANOVA and t-test. The results confirm the meaningful differences between the cases with the same density but different spatial design characteristics, which imply a correlation between these factors. This potential correlation can help to formulate a more precise definition of density, which is related to some of the design factors.