Energy and environmental impact of recycled end of life tires applied in building envelopes

Abstract

This paper presents an initial investigation into the application of end of life vehicle tires as building envelope materials for a residential building design in Calgary, Canada. Two applications of tires are investigated: shredded tire chip insulation and structural whole tires filled with earth, in two envelope locations: walls and floors. Thermal properties such as thickness and conductivity, and the effective energy performance are analysed in EnergyPlus. OpenLCA is employed to assess the embodied energy benefits against conventional materials.Earth-filled whole tires constituting floor slabs are the most efficient application, performing equivalently to an energy efficient code case (0.03% decrease in annual energy use intensity (EUI)). Tire chip insulation performs more efficiently in floors than walls with EUI deviations of 28–67% in walls and 0–6% in floors. Whole earth-filled tires performed similarly to the structural concrete components in both walls and floors (3% and 0.6% EUI increase respectively). The most efficient application, whole tire floor slab, is shown to require 74% less embodied energy at 6.13MJ and 89% less global warming potential at 0.43kgCO2eq for one tire as compared to a precast concrete floor slab of the same area, with effects predominantly due to transportation and excavation of on-site earth.