Historic buildings represent our cultural heritage and identity. Due to their age and building tradition, they are extremely vulnerable to seismic excitations, as confirmed by the recent earthquake in the city of Zagreb. In addition, historic buildings are among the buildings with the worst energy performance and very low indoor comfort. In the scope of this paper, the seismic and energy integrated approach is applied to a typical multi-residential building in Zagreb historical downtown. The main focus of the paper is on building envelope energy efficiency measures. Different variants of thermal insulation (external and internal), secondary windows (maintaining existing ones vs. new efficient ones) and ventilation (natural vs. mechanical with heat recovery) are analysed in terms of building energy performance (3D level). Furthermore, replacement of existing technical systems and installation of RES are also considered. Moreover, the acceptability of the proposed retrofitting solutions for opaque elements is evaluated in terms of thermal bridges (2D level) and long-term hygrothermal performance (1D level). Finally, the results show that it is possible even for a 100-year-old building to meet the current national primary energy requirements for new buildings and provide good indoor environmental quality for occupants while respecting the cultural heritage.

历史建筑代表了我们的文化遗产和身份。由于它们的年代和建筑传统，它们极易受到地震激发的影响，最近萨格勒布市发生的地震证实了这一点。此外，历史建筑是能源性能最差、室内舒适度极低的建筑之一。在本文的范围内，地震和能源综合方法应用于萨格勒布历史悠久的市中心的典型多住宅建筑。本文的主要重点是建筑围护结构节能措施。在建筑能源性能（3D 级别）方面分析了隔热（外部和内部）、辅助窗户（维护现有窗户与新的高效窗户）和通风（自然与机械与热回收）的不同变体。此外，还考虑更换现有技术系统和安装 RES。此外，根据热桥（2D 水平）和长期湿热性能（1D 水平）评估了针对不透明元件提出的改造解决方案的可接受性。最后，研究结果表明，即使是一座拥有 100 年历史的建筑，也有可能满足当前国家对新建建筑的一次能源要求，并在尊重文化遗产的同时为居住者提供良好的室内环境质量。