AbstractThis thesis evaluates indoor overheating in buildings, focusing on the performance of design strategies, assessment criteria and forecasting at design stage. Given a warming climate, resilient and energy-efficient building design could mitigate carbon emissions while promoting occupant health and wellbeing. However, these predicate on the robustness of compatible design strategies and methods to evaluate performance — aspects currently under scrutiny and here studied around three key questions.
How do passive design strategies influence overheating in free-running buildings? Firstly, unintended consequences of strategies for improved energy-efficiency was examined with regard to overheating, focusing on increased insulation as an important but controversial measure. A large computational parametric study was conducted and analysed through a novel framework based on data-mining techniques. Results show increased insulation plays a minor role in overheating and that it favours lower indoor temperatures if purge ventilation is available, exacerbating them otherwise. The underlying physical mechanism for these results was presented. These findings suggest energy policy should consider the compatibility of its recommended measures.
How can physiological models inform building design resilient to overheating? Secondly, the severely hot indoor environments of refugee shelters in the desert was examined through different overheating criteria to improve their design process. In agreement with empirical observations, results based on validated simulations show shelters develop excessive annual overheating as evaluated through comfort and heat strain models. Appraised passive strategies could eradicate the severest instances of overheating. Findings suggest physiology-based overheating criteria could be integrated in a cyclic design process where thermal assessments are routinely performed and acted upon until adequate indoor environments are guaranteed.
To what extent can high-fidelity annual building simulation predict indoor thermal conditions in free-running buildings at design stage? The last study compared predicted indoor temperatures through building simulation to those observed in prototyped shelters. Models based on design specifications and expert judgement loosely bound observations in unoccupied shelters, whilst model calibration improved goodness-of-fit metrics and qualitative agreement substantially. Findings suggest overheating prediction at design stage is fragile and that aid-agencies should adopt simulation and prototyping to assess and improve indoor thermal conditions in shelters.
|Date of Award||19 Feb 2020|
|Sponsors||University of Bath & La Caixa Foundation|
|Supervisor||Sukumar Natarajan (Supervisor) & David Coley (Supervisor)|