AbstractThis paper discusses the influence of passive façade design of a detached residential building on its energy performance. The research consists of a parameter analysis performed using commercially available software to assess the influence of different façade wall structures, glazing types, and window-to-wall ratios (WWRs) on the energy required for heating and cooling of a detached building with a sunspace. Eighteen variants of façade wall structure (W1–W18) and 20 variants of façade window glazing type (G1–G20) were created for the base model of a building with a sunspace (Model-FW) for the purpose of investigating their influence on energy consumption in the building. All variants of the base model were examined for WWR=20%, WWR=40%, and WWR=60%. The research was conducted for the location of the urban area in the city of Niš, Serbia. The analysis of the results showed that the best-performing façade wall structure in terms of heating energy consumption was Variant W1, which consists of a 0.40-m-thick concrete layer, 0.14-m-thick expanded polystyrene (EPS) thermal insulation layer, and a render/plaster layer on the outside and the inside with the total thickness of 0.03 m. The W1 variant had the largest thermal mass and thermal insulation thickness of all considered variants. Regarding the total energy required for heating and cooling, in the most favorable W1 model, the energy savings were 75.14% (WWR=20%), 35.04% (WWR=40%), and 17.15% (WWR=60%). The analysis of different glazing types showed that triple low-emissivity glazing performed the best in terms of heating energy required for a building with a sunspace. Among the considered models, benefits from triple glazing systems in terms of total energy consumption were 41.59%, 61.04%, and 47.70% for WWR=20%, WWR=40%, and WWR=60%, respectively.