Feasibility study of “green” insulation materials including tall oil: Environmental, economical and thermal properties

•The green insulation materials are produced by using C, FA, RHA and ETO.•Thermal conductivity and density properties are determined.•Environmental and economical analyses are investigated by using LİNGO programme.•Insulation thickness is optimized for externally isolated walls in Elazığ, Turkey.•Energy saving, payback periods, sensitivity analysis and emissions are calculated. In the present work, insulation materials are produced by using clay (C), fly ash (FA), rice husk ash (RHA) and epoxidized tall oil (ETO). Density and thermal conductivity properties of these materials are analyzed. Environmental and economical analyses of sample with code T36 as insulation material are numerically investigated by using a computer program developed in LINGO. The optimum insulation thickness of this insulation material applied externally on wall for Elazığ city of Turkey, energy saving over a lifetime of 10 years, payback periods, sensitivity analysis and emissions of CO2–SO2 versus insulation thickness are calculated for the four energy types.