Uplifts aim to put future homes on track

Decarbonising buildings is central to achieving the UK government's net-zero target for 2050. However, these changes will not happen overnight, so the housebuilding industry is being set incremental targets along the way.

The Future Homes Standard, along with the Future Buildings Standard for non-domestic properties, were proposed as part of the government's two-part consultation on changes to the Building Regulations.

From 2025, new buildings must be net-zero-ready; which in practice means that they have to be constructed to a high standard of energy efficiency with low-carbon heating, avoiding the need for costly retrofit. New homes built to the Future Homes Standard should generate only 20–25% of the emissions of homes built to current requirements.

Alongside these uplifted standards the government published two new Approved Documents in December, which also took effect on 15 June. Approved Document O includes measures to mitigate the effects of overheating, and Approved Document S introduces obligations to install infrastructure for the charging of electric vehicles.

The aim is that new homes complying with the uplifted requirements will reduce carbon emissions by 31% compared with those built to current standards. This will be achieved through a combination of low-carbon heating and increased fabric standards.

The interim uplift will apply to individual buildings, rather than across whole development sites, as soon as work commences. This means that the Building Regulations will no longer be locked in at the start of works. Phased developments may therefore find that different regulations apply to different parts of the site over the course of the build programme.

Transitional arrangements have been put in place for situations where a building notice, initial notice or full plans have been submitted to a local authority before 15 June. In this case, there will be no obligation to comply with the interim uplift in regulation, provided that building work commences on site within 12 months.

The target emission rate will no longer be used as the primary performance metric, in recognition that carbon emissions alone do not give a full picture of the energy performance of building performance over time. This is because it will become increasingly difficult to determine whether emissions reductions are a result of improved energy efficiency or a decarbonised electricity grid.

Part L requires that efficient and decentralised systems that use renewable sources are given full consideration before building work starts. Heat pumps or connection to low-carbon district heating systems are identified as a way to meet this criterion, moving away from traditional fossil-fuel boilers.

This forms part of the government's wider decarbonisation approach, aligning with the heat and building strategy to transition to low-carbon heating ahead of net-zero 2050.

There is emphasis on using all practicable means to achieve passive cooling before resorting to mechanical options. This is intended to avoid increasing the building's energy usage, as any mechanical systems must meet the Part L performance metrics.

Designers also need to consider carefully how they meet requirements for increased airtightness under Part L, so they do not affect the building's ventilation and air quality standards.

The new Part O meanwhile brings together previous regulation on overheating, and requires that new homes are kept at a comfortable temperature. New buildings must be designed to limit unwanted solar gains and minimise and remove any excess heat.

It is essential that the design phase aims to fulfil these requirements, as compliance may be difficult to achieve further down the line. High-risk areas – largely in London, although there are some in central Manchester – must adhere to more stringent standards than other parts of England, where there is only a moderate overheating risk.

Part S requires all new residential and mixed-use buildings – as well as buildings undergoing a material change of use or major renovations – to install charge points for dedicated parking spaces.

There are some exemptions, though. These include a cap on the cost of each charge point to £3,600, and exceptions for enclosed or open-sided car parks, while the government is further investigating fire safety concerns related to charging.

This entails producing both a design-stage BREL report, before building work commences, and an as-built BREL report that shows the new home has been constructed as per the energy-efficient design specifications.

Local building control and SAP assessors also require photographic evidence specific to each dwelling, to document details of the build during construction.