This work is part of a research project about optimization of parametric bioclimatic design. We develop two bioclimatic indexes of heating and cooling for typical winter and summer days respectively, which are optimized by means of genetic algorithms (GA) [1]. The object is a high-rise building with multiple uses, located in a plot of urban land, according to Buenos Aires City Environmental Code [2]. The efficient envelope fulfils the Law of Thermal Conditioning in Buildings for Buenos Aires City and IRAM Standards 11604 [3] and 11659/1-2 [4]. After parameterizing the building geometry, we introduce solar thermal loads, transmission loads and internal loads. We employ our own climatic data from the Laboratory: hourly solar radiation and temperature. Then, we run the program consecutive times in order to obtain a set of solutions, which have equivalent energy performance but different spatial configuration. We utilize a genetic algorithm (GA) to optimize the process [5].Based on the results, we can analyze which variables influence the energy performance of the alternatives. This tool proves to be effective to design and optimize architectural solutions for a high-rise building, while giving the designer more options than traditional design method. We verify the hypothesis of the incidence of envelope geometry on energy demand by means of these new indexes. The calculations of these new indexes-B heat and B cool-let us evaluate simultaneously both parameters, providing a common basis of comparison: 24-hour energy demand of typical winter and summer days. We can affirm that energy efficient design cannot let apart summer condition for our bioclimatic zone (humid temperate) IIIb (IRAM 11603) [6]. Nevertheless, the above mentioned law in Buenos Aires Province only requires a minimum Gheat (IRAM 11604), taking into account only winter condition. The same happens with IRAM Standard 11900 about energy efficiency labelling.electronic document is a "live" template. The various components of your paper [title, text, heads, etc.] are already defined on the style sheet, as illustrated by the portions given in this document.