Addition of granular phase change materials (PCMs) and graphene to a cement-based mortar to improve its thermal performances

•A cement-based mortar enhanced with granular PCM and graphene was investigated.•Two equal applications in a radiant floor system were examined at lab scale.•Lower floor temperature fluctuations if compared with a standard mortar.•Simulation showed higher room temperature with enhanced mortar when system off.•A lower enhanced mortar was simulated as option for existing building refurbishment.