Hormigón Infraligero

Infra-lightweight concrete applied to cast-in-situ structural elements with fair-faced surfaces and good thermal insulation

Fair-faced concrete does not only possess high visual qualities. Monolithic concrete structures are also particularly durable, and the fact that no plastering or cladding is required leads to cost savings and makes buildings more sustainable and easier to recycle. However, due to the high thermal conductivity of normal concrete, fair-faced concrete without insulation causes prohibitive heating costs in cold countries. Infra-lightweight concrete with a dry bulk density of less than 800 kg/m³ and the corresponding advantageous thermal properties promises to overcome this problem while maintaining the advantages. At the Technical University in Berlin such infra-lightweight concrete was developed and to prove its practicality a cast-in-situ single family house was built with it using glass fiber bars as reinforcement. This paper describes this new concrete mix and its properties. It elaborates on the structural implications when working with infra-lightweight concrete. Design and construction of the house will also be presented.