Cleaning Methods for Historic Building Facades: A Systematic Review and Decision-Making Framework

No single cleaning method universally suits historic building facades; effective intervention demands material-specific and climate-specific diagnostics. A systematic review of 78 peer-reviewed studies (1990–2025) across six linguistic traditions introduces a multi-criteria decision-making framework that operationalizes the principle of minimum intervention, emphasizing necessity assessment, substrate characterization, contaminant diagnosis, and post-intervention monitoring. The study highlights femtosecond laser cleaning, biocleaning, and nanostructured controlled-release gels as promising emerging technologies for sensitive materials in arid and semi-arid climates, where moisture ingress and salt crystallization pose significant risks. Applied to Golestan Palace—a UNESCO World Heritage Site with diverse facades—this approach underscores the need for pollutant control at source, targeted advanced cleaning, and intelligent monitoring to ensure sustainable conservation.

Khalili Zonouz, H. (2026). Cleaning Methods for Historic Building Facades: A Systematic Review and Decision-Making Framework. Zenodo. https://doi.org/10.5281/ZENODO.21378309