The Bureau of Energy Efficiency in India launched the Eco-Niwas Samhita (Part I: Building Envelope) in December 2018. This report was prepared by Greentech Knowledge Solutions in collaboration with the CEPT University and supported by the Shakti Sustainable Foundation. The report provides a database of walling materials that are used in the construction of buildings across the country, which have various thermophysical properties and can be used for the accurate estimation of Residential Envelope Transmittance Value (RETV) for the implementation of ENS.