The refinement of architectural space plays a catalytic role in the building's energy balance. A different configuration on the deep energy building retrofit is presented on this paper, by proposing mainly strategies that hierarchize in a high position the invigoration of the building's architectural design principals. These space qualities enable diversity of occupancy, environmental variability and facilitate the building envelope to operate efficiently as climate moderator. The main working hypothesis claims that bioclimatic trends, derived from primary architectural decisions of the early design phase, predispose the final energy performance of the existing building.Based on that, the alternative retrofit proposal called Architectural Energy Retrofit (AER) strategy, focuses on the energy genetic code of these basic architectural features. It argues that their holistic revival and refinement, indoors and outdoors will pave the way for the building's energy retrofit and the space's regeneration. As a case study to test this theory, an old and energy-consuming school complex is selected. By applying solely architectural interventions, a reduction of 44% energy demands was achieved. The results highlighted the challenges of "quantifying" the energy efficiency of architecture. However, by exploring and focusing on the non-energy, co-benefits, it also seeks to expand the perspective of energy efficiency beyond the traditional measures, by identifying and measuring its impacts across many different spheres. AER, as a counterproposal, wishes to add a new base of discussion on deep energy retrofit strategies as it follows a diametrically opposed direction than the typical practices, The building instead of being "sealed" and its environment kept strictly controlled, it "opens" and interacts with its surroundings. (C) 2017 Elsevier B.V. All rights reserved.