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@article{190118,
        author = {Saud Ahmad and Mohd Suhaib Zamir},
        title = {Sustainable Retrofitting Of Heritage Buildings: Conservation-Compatible Energy Efficiency Strategies Through Systematic Evidence Synthesis},
        journal = {International Journal of Innovative Research in Technology},
        year = {2026},
        volume = {12},
        number = {8},
        pages = {2140-2148},
        issn = {2349-6002},
        url = {https://ijirt.org/article?manuscript=190118},
        abstract = {Historic buildings make up around 30% of the European building stock but use 40% more energy than modern buildings of the same type, thus posing a major challenge to sustainability. This systematic review of 12 peer-reviewed studies (2011-2025) confirms that energy-saving retrofits compatible with the buildings original function result in 50-70% reduction of the energy used for daily operational activities while the heritage values are preserved. The four international case studies (Greece, Slovakia, Italy, China) demonstrate the technic al feasibility in a variety of contexts: Kaisariani social housing (Athens) lowered its primary energy consumption by 97%; rammed earth buildings (China) achieved a 72% reduction with payback periods of 10 years. EN 16883:2017 standard sets out a universal five-stage assessment process combining heritage preservation principles (minimum intervention, reversibility, compatibility) with energy performance requirements (EPBD 2018/844/EU, nZEB standards). The main findings: moderate retrofit measures (50-70% reduction) are realizable in 70% of the projects; deep retrofits (70-90%) in 20%; nZEB possible in 10-15% with extensive intervention. Economic feasibility was demonstrated by the nine to 12 years payback periods across the case studies. The obstacles to the implementation (cost premiums, lack of skills among professionals, regulatory conflicts) can be overcome by heritage-specific incentives, integrated training programs, and simplified local regulations. There is no doubt that, on the one hand, saving energy and, on the other hand, conserving the architectural heritage are not contradictory goals but, in fact, complement each other if the application of systematic interdisciplinary methodologies is ensured. This paper offers a comprehensive evidence synthesis, validated retrofit strategies, comparative case study analysis, and evidence-based policy recommendations for stakeholders.},
        keywords = {Heritage buildings, energy retrofitting, conservation-compatible design, EN 16883:2017, nearly zero-energy buildings (nZEB), Building Integrated Photovoltaic (BIPV) systems, embodied carbon, sustainable retrofit strategies, lifecycle assessment, regulatory frameworks},
        month = {January},
        }