A computational and empirical analysis of the thermal performance of insulating concrete formwork

The research presented in this EngD thesis focused on Insulated Concrete Formwork (ICF), a site-based, Modern Method of Construction (MMC). An ICF wall consists of modular prefabricated Expanded Polystyrene Insulation (EPS) hollow blocks and cast in situ concrete. The blocks are assembled on site and the concrete is poured into the void. Once the concrete has cured, the insulating formwork stays in place permanently, providing very low U-values and high levels of airtightness. ICF is often thought of as just an insulated panel acting thermally as a lightweight structure. There is a view that the internal layer of insulation isolates the thermal mass of the concrete from the internal space and interferes with thermal interaction. Despite evidence of ICF’s enhanced thermal storage capacity (compared to a lightweight timber-frame panel with equivalent insulation), there is still a gap in understanding when attempting to quantify the effect of the thermal mass within ICF.

Using computational analysis (Building Performance Simulation - BPS) and empirical evaluation (monitoring data), the aim of the EngD research was to analyse the aspects that affect the thermal performance of ICF; to develop an understanding about its thermal behaviour and its response to dynamic heat transfer; and, to investigate how the latter is affected by the inherent thermal inertia of the concrete core. [Continues.]