Turkey is undergoing a major transformation process. This process, also called urban renewal, takes place at neighborhood and building (on-site transformation) scales. The literature focuses on transformation problem of the neighborhood scale; however, the characteristics of the problems associated with building scale transformation differ. One of these is texture differentiation. With the on-site renewal process, the existing urban texture and its micro-climate characteristics change. An existing low-rise building in the street is transformed and built as a high-rise multi-storey building, which shades the neighboring buildings in the texture. In this case, it can be predicted that the energy consumption performance of existing buildings will be affected. The aim of this study is to examine the effect of reconstructed high-rise buildings on existing buildings in the texture in terms of energy performance. The study area is chosen as Suadiye (Kadıköy, Istanbul) because of the high urban renewal activity. Using computer simulation methodology, the energy performance of a reference building was calculated for three texture scenarios: base situation (rural texture), 1960 urban texture and 2019 texture (after renewal). In this study, in which the building envelope is kept constant, the effect of the urban texture on the building energy consumption is clearly observed. According to the results of the study, lighting and heating energy consumption of the reference building increased during the transition from rural to 1960 texture. With the urban transformation law numbered 6306 enacted in 2012, it would be possible to save energy by optimizing the urban texture. However, in practice, it is seen that energy consumption of the reference building is increased more in the transformation from the 1960 texture to the 2019 texture. In other words, texture change has increased energy consumption. One of the goals of this high-cost transformation process, which is necessarily experienced with earthquake risk in the first place, was stated as providing energy savings. For this purpose, envelope insulation is mandatory in reconstructed buildings. However, independent of the building envelope, the characteristics of the urban texture also play an important role in energy consumption. For this reason, the optimization of the urban texture should be evaluated as a part of the transformation process and legal regulations should be implemented to support this. Potential impact analysis should be done before intervening in the urban texture.