Microbiologically incorporated cementitious materials to recuperate the activities and toughness of the concrete structures are a new aspect of research work in the current era. The uses of different chemicals and additive in concrete composites sometimes cause health problems which are environmentally unacceptable. In this study we have designed an eco-friendly bio-engineered with high strength and more durable concrete/geopolymer material by incorporating hot spring bacteria. A novel thermos-stable and high pH tolerant silica leaching protein ((M.W. ~ 28KDa) originally isolated from one of the hot spring’s bacteria BKH2 of Bakreshwar, West Bengal [1, 2] has been observed for responsible for production of high-performance structural materials. The corresponding gene of the protein has been identified and cloned into B. subtilis bacterial strain to develop an eco-friendly microbial agent [2, 3]. The transformed bacterial cells, when incorporated to the cement-sand mixture and or fly ash mixed cement-sand mixture, develop a sustainable and energy efficient material, which is useful for construction purposes [3, 4]. Improvement of compressive strength (> 30 – 40%), ultrasonic pulse velocity, sulphate and chloride ions resistant and decrement of water absorption capacity are noted in the bacteria amended mortar/concrete/geopolymer specimens. Micro-structural analyses confirmed the formation of a novel Gehlenite (Ca₂Al₂SiO₇) phase besides calcite deposition inside the matrices of the transformed bacteria-amended cementitious materials [3-5]. This development significantly increases the true self-healing property and aims towards the production of green cement-alternative by using cent-percent fly ash which is sustainable for a prolonged period [5]. This implies lesser requirements of cement and lowers the cost of construction. This study demonstrates a new approach towards the development of Green Home technology by reducing Green House effect of cement production.