Sustainable energy synergy for historic building: Conservation retrofit solution of hygrothermal control.

[Display omitted] • Improving energy efficiency in centennial Korean historic buildings via retrofit. • Development of retrofit with diatomaceous earth and phase change materials. • Reduce condensation risks without damaging the building's historical value. • The historic building withstands outdoor climates despite no insulation. • Save energy solely with interior finishing materials, without insulation. Historic buildings require groundbreaking retrofit technology to prevent damage to the exterior appearance of the exterior. This paper presents a retrofit technology to increase the energy efficiency of old historic buildings that were heavily exposed to hygrothermal conditions. The study employed an innovative interior finishing material composed of diatomaceous earth and microencapsulated phase change materials to achieve a trade-off between performance improvement and heritage conservation. Based on previous studies, an optimal formulation was identified through evaluation. The developed retrofit technology displays crack resistance, high latent heat capacity, and remarkable moisture stability. Our analysis revealed that the application of this retrofit solution would effectively reduce moisture levels and mitigate condensation risks without compromising the building's historical integrity. The retrofit technology yielded a reduction in cooling and heating energy consumption by over 10% while concurrently addressing moisture stability through a decrease in the thermal transmittance of the exterior walls. By utilizing passive technologies and the unique properties of diatomaceous earth, our pioneering research on the sustainable preservation of historic buildings has laid the foundation for widespread retrofit adoption in heritage conservation. [ABSTRACT FROM AUTHOR]