Printing thermal performance: an experimental exploration of 3DP polymers for facade applications

The decarbonisation of the building sector requires the development of building components that provide energy efficiency while producing minimal environmental impact. We investigate the potential of polymer 3D printing (3DP) for the fabrication of mono-material translucent facade components, whose properties can be tailored according to climatic conditions and functional requirements. These components bear the potential to reduce energy consumption in buildings and, at the same time, can be fabricated with minimal environmental impact thanks to the recyclability of the feedstock material. In this study, we explore the effect of component geometry on the thermal insulation properties of 3DP objects with bespoke internal structures. Different prototypes are fabricated using a robotic polymer extruder, and their thermal properties are measured following a hot-box test method. The experimental results are then used to calibrate a heat transfer simulation model describing the joint effects of conduction, natural convection and infrared radiation through the components. We show that it is possible to fabricate insulating polymer components providing thermal transmittance ranging from 1.7 to 1 W/m 2 K only by changing the internal cavity distribution and size. This proves the possibility of designing 3DP thermally-insulating components for different climatic conditions and requirements. This study provides the first insights into the thermal behaviour of polymer 3DP facades on a large scale. The results suggest that this innovative manufacturing technique is promising for application in facades and encourages further research toward performant and low-embodied energy 3DP building components.