This study begins by recognizing that the visual attractiveness of a building is one of the most influential factors that shape people’s perceptions of a city or place. As such, examining the visual consequences of architecture at the early design stage is an important issue for the built environment. The study assesses the pre-attentive visual responses that shape immediate human responses to architecture., including their visual complexity and strength of attraction. Visual complexity is assessed by measuring fractal dimension (D), and strength of attraction (S) is assessed by measuring visual attention data. Importantly, both D and S values are limited to the innate measures of visual complexity and attractive strength. The results indicate clear differences in attractive strength between Modern, Postmodern and Neo-modern houses, with the results higher for the Postmodern houses than for the other two types.