Impact of inter-building longwave radiative exchanges on building energy performance and indoor overheating

Despite inter-building longwave radiative exchanges playing an important role in determining building energy and environmental performance, simulation tools (e.g. EnergyPlus) simplify this by assuming the surface temperature of surrounding buildings to be equal air temperature, therefore cause bias. Here we propose a ‘spin-up’ approach update external using either or isolated temperatures. Neighbourhoods with different plan area fractions (? P ) are analysed assess impact on temperatures, cooling heating demand as well indoor overheating degree hours. Using default EnergyPlus method causes large bias all metrics dense urban = 0.6) climates assessed (cf. new method): wall (3 °C less, midday median), annual for (17.1% less) (6.2% higher), hours during day (>28 °C, 24.5% night (>26 60.1% less). These biases larger at lower latitudes. Thus, neglecting surroundings' influence radiation impacts critical design considerations thermal performance areas. An account proximal should used. • Inter-building simulated iterative/spin-up EnergyPlus. Inaccurate adjacent temperatures lead simulation. Denser neighbourhoods latitudes more sensitive calculation.