In February the Committee on Climate Change (CCC) released a 135-page report on the readiness of our housing stock to cope with the consequences of a changing climate. It does not make very easy reading, concluding that our homes are far from ready, and that much work is needed to reduce the contribution of the places where we live to UK carbon emissions.
With homes accounting for 15% of UK emissions, and the appliances in them a further 4%, the CCC makes a detailed case for the rapid decarbonisation of our dwellings. It calls for a significant shift to low carbon heating, for no new homes to be connected to the gas grid from 2025, for a significant programme of energy refurbishment of existing houses, and for the Treasury to explore potential financial support for energy efficiency works.
Saying that ‘homes of the future are needed today’, the committee adds that ‘decarbonising and adapting the UK’s housing stock is critical for meeting legally binding emissions targets by 2050 and preparing for the impacts of climate change. The UK government, householders and developers need to implement policies and measures now that ensure new and existing homes are fit for the future’.
The committee acknowledges that reductions in emissions from UK housing have stalled, noting that efforts to adapt the housing stock for higher temperatures, flooding and water scarcity are falling far behind the increase in risk from the changing climate. Government’s own research shows all new-build homes are at risk of overheating, and household water consumption needs to fall from around 140 litres per person per day to well below 100 by 2050 to reduce the risks of future water scarcity.
We cannot meet our 2050 target without a near complete decarbonisation of how we heat our homes
The report argues that we cannot meet our 2050 target (or future ambitions for net-zero emissions) without a near complete decarbonisation of how we heat our homes. Retrofitting measures offer substantial opportunities to address climate risks; the CCC says that the ‘quality, design and use of homes across the UK must be improved now to address the challenges of climate change. Doing so will also improve health, wellbeing and comfort, including for vulnerable groups’.
The report says the forthcoming reviews of Building Regulations are an opportunity to make sure new homes are built for the future, and are low carbon and energy efficient, have safe moisture levels and excellent indoor environmental quality, and are climate resilient.
The report identifies five priorities for government action to deliver:
Low carbon, energy efficient homes that use heat pumps, and a fully fledged heat strategy with a clear trajectory of standards set well in advance, funding for low carbon heat from 2021, and incentives for householders.
Thermal comfort, ventilation and indoor air quality, using existing technology to deliver homes that stay warm in winter and cool in summer, are ‘moisture-safe’ and have excellent indoor air quality. This requires a holistic approach to design, build and retrofit, standards for overheating, and passive cooling used in preference to air conditioning. Ventilation regulations must keep pace with improvements in energy efficiency and be better coordinated with Part L.
Electrical energy efficiency, flexibility and peak management to reduce energy demand for hot water and appliances, by insulating hot-water tanks and pipes, installing hot-water thermostats and low energy lighting, and using highly efficient appliances. Batteries and smart appliances will allow householders to use energy more flexibly, and help shift consumption away from the peak.
More focus on the whole-life carbon impact of new homes, including both embodied and sequestered carbon, with a substantial increase in the use of wood in construction to displace high-carbon materials such as cement and steel.
Lower water use in homes to enhance water-supply resilience through water-efficiency measures, increased metering, compulsory water-efficiency labelling, improved behaviours and more ambitious Building Regulations. Also, better alignment of water and energy-retrofit programmes.
The CCC makes 36 recommendations to government for action, more than half relating to the Building Regulations. However, with a review of Parts L and F – including work on overheating – now under way, there is a significant opportunity to be seized. And, if that was not enough, the Chancellor’s Spring Statement announced that a ‘Future Homes Standard [is] to be introduced by 2025, future-proofing new-build homes with low carbon heating and world-leading levels of energy efficiency’.
- Dr Hywel Davies is technical director at CIBSE