The thermal performance of the glass fibre-reinforced gypsum (GFRG) demo building at IIT-Madras was analysed through field measurements. Dr A Meher Prasad, Professor, Structural Engineering Division, Department of Civil Engineering, IIT Madras, shares more… In-situ thermal measurements showed that the GFRG demo building was around 2oC cooler compared to an adjacent conventional building during the harsh summer. Further, tests have shown that GFRG panels absorb very less water. The water absorption of the panels is found to be less than 2 per cent even after 24 hours of immersion in water; the panels are therefore water-resistant. But as GFRG buildings system are prefabricated systems, all the construction joints (including the vertical and horizontal wall panel joints) should be treated with waterproofing compounds. Advantages over conventional buildings The GFRG building system has a number of advantages over conventional buildings: High speed of construction: GFRG demo building in IIT-Madras with four flats in two storeys (total 1,981 sq ft) built within a month Less built-up area for the same carpet area: Wall panels are only 124 mm thick Low embodied energy and carbon footprint: Significant reduction in use of cement, sand, steel and water; recycling of industrial waste gypsum Lower cost of structure: Savings in materials; no plastering Lesser building weight (panels weigh only 44 kg per sq m), contributing to savings in foundation and reduction in design for earthquake forces, particularly in multi-storeyed construction Buildings up to 8-10 storeys can be designed using this load-bearing system, without the need for beams and columns Excellent finishes of prefabricated GFRG panels—used for all the walls, floors and staircases, with minimal embedded concrete: no need for additional plastering The use of GFRG panels not only facilitates fast construction but reduces labour requirements. Better thermal performance in comparison to conventional building. Green material While benefiting the mass-housing segment, GFRG also serves as sustainable technology. It is environment-friendly, as it utilises industrial waste, and the construction minimises the usage of scarce and energy-intensive materials such as cement, sand, steel and water. There are no safety and health issues associated with the product. Gypsum is an inert material and GFRG building construction entails far less embodied energy (from the manufacture till the completion of construction) compared to conventional construction using brick, reinforced concrete or precast concrete. Hence, GFRG has been confirmed as a green material by the United Nations Framework on Climate Change (UNFCC). - SERAPHINA D’SOUZA