Interest in the UK regarding the design of passively ventilated and cooled buildings has resulted in much work on the thermal performance and likely environmental impact of such buildings. Little work assessing the impact of the passive design approach on the construction process has been undertaken. This issue is examined herein, through the initial development of a methodology quantifying the relationship between passive environmental control (PEC) and the construction process, leading to a means of classifying buildings according to their prefabrication strategy.