Outcomes From a Randomized Control Trial of Home Energy Upgrades in Victoria, Australia

OBJECTIVES: Poor housing quality is linked to higher morbidity and mortality, especially among vulnerable groups such as the elderly and chronically ill, who spend more time at home. Improving indoor temperatures through home upgrades can offer health benefits, but evidence from Australia is lacking. This trial provides evidence on the energy and health outcomes of a home energy upgrade to a group of vulnerable, elderly Australians.

METHODS: The Victorian Healthy Homes program (VHHP) run over three years and was a staggered, parallel group clustered randomised controlled trial (RCT) on 1000 households. Home upgrades were implemented either before (intervention group) or after (control group) the winter period (22 June – 21 September), with outcomes measured over three months. Various regression models adjusted for age, sex, geographical area, and year were conducted, along with an cost consequence and cost benefit analysis.

RESULTS: Results show that a low-cost upgrade ($2,809 on average) had notable benefits. Indoor temperatures rose by one-third of a degree overall and half a degree in the morning, reducing exposure to temperatures below 18°C by 43 minutes per day. Gas consumption decreased by 5.53 KWh/day, though electricity use remained unchanged. Health benefits included reduced breathlessness and improved quality of life, particularly in mental health and social care. The intervention group showed significant improvements in the mental health component of the SF-36 score and ASCOT scores post-winter. The program resulted in healthcare savings, $887 per person over winter. A cost-benefit analysis predicted the upgrade would be cost-saving within three years, with a net saving of $4,783 over ten years, predominantly from healthcare savings.

CONCLUSIONS: The VHHP is the first Australian initiative of its kind, featuring a robust RCT. Its findings could significantly influence housing policy at state and national levels, especially with the increasing recognition of climate and housing impacts on health and well-being.