Developing an alternative method to determine the heat transfer coefficients of dwellings in warmer climates

Chard, E

Abstract

Whole house heat loss test methods are used to determine the heat transfer coefficient (HTC) of dwellings. Having reliable methods of measuring as-built performance makes it possible to improve the energy efficiency of dwellings, aiding in the global endeavour to reach net zero-carbon. However, there is a gap in current research, as prevailing methods can only be carried out when external climatic conditions are colder, making them ineffective in warmer climates, including outside of the winter months in temperate climates.
Therefore, the aim of the research presented in this thesis is to determine whether it is possible to develop a heat loss test method capable of determining the HTCs of domestic buildings in warmer climates. Using DesignBuilder, a building energy performance simulator, the alternative method was developed and performed on a simple model of the Barratt Zed House, a modern dwelling located on the University of Salford’s Peel Park Campus. For comparison purposes, the well-established co-heating method was also performed; firstly, in real conditions on the Zed House itself to determine an as-built baseline HTC (137.2 ± 12.2 W⸱K-1), and then on the simplified model of the Zed House in DesignBuilder to determine a simulated baseline HTC (93.6 ± 5.3 W⸱K-1).
Through development and analysis of the alternative method, the research explored cooling systems, testing periods, aggregation intervals and temperature conditions. By considering protocols such as statistical validity and collinearity, the most appropriate HTC from the resulting fifteen data sets was determined as 96.8 ± 12.7 W⸱K-1. Additional analysis was then carried out by simulating the alternative method on the Zed House model in three Australian climates: Darwin, Brisbane and Perth. Perth provided the only statistically valid HTC (81.8 ± 19.1 W⸱K-1).
Overall, the alternative method opens new doors for measuring the performance gap in warmer climates. However, the alternative method still had some difficulty performing well in the UK summertime climate, and high levels of solar irradiance also seemed to impact the alternative method’s performance.

Citation

Chard, E. (2022). Developing an alternative method to determine the heat transfer coefficients of dwellings in warmer climates. (Dissertation). University of Salford

• Thesis Type: Dissertation
• Deposit Date: Apr 12, 2023
• Publicly Available Date: Apr 15, 2025
• Award Date: Oct 14, 2022