The aim of this project was to investigate and quantify the impact of certain early design decisions on the solar potential of a target building placed in an urban context. This was done through a parametric study based on the successive variation of specific design parameters: building height, distance, reflection and orientation. A Design of Experiment (DoE) approach was adopted with a 2-level fractional factorial design. For each new 3D model obtained, an irradiation simulation was conducted for the climates of Geneva, Phoenix and St. Petersburg. Results were processed to identify the main design parameters of influence, quantified by the main effect and percentage contribution, and interpreted through various representations such as irradiation maps and DoE mean plots. Results showed the main influential design parameter to be, for all climates, the height of the surrounding buildings, followed by the distance between the central and surrounding buildings.