Changes to the Building Regulations to help deliver net zero

In a new series of updates, our Built Environment Construction & Engineering team will look at recent developments that have taken place as the UK aims to build momentum on its journey to net zero. 

In October, just days before the start of COP26 the UK Government published its eagerly anticipated net zero greenhouse gas emissions strategy (Net Zero Strategy), which sets out a delivery pathway for net zero by 2050 showing indicative emissions reductions across a number of sectors including a section on domestic energy consumption and decarbonising the way we heat and power buildings. Achieving net zero means not adding to the sum total of carbon emissions in the atmosphere- a key part of the fight against climate change.

On the same day as the Net Zero Strategy was published, the UK Government also published a separate heat and buildings strategy (Heat and Buildings Strategy), which outlines the importance of improving energy efficiency across the residential property sector and provides detail on decarbonising homes. The Heat and Buildings Strategy sets a goal to decarbonise the buildings sector by between 47% to 62% by 2035.

The UK has close to 30 million buildings which include some of the oldest building stock in Europe accounting for almost 20% of the country’s emissions. In addition, heating and powering buildings currently accounts for 40% of the UK’s total energy usage. It therefore comes as no surprise that, in the current climate (pun intended), the need to review policy and legislation to tackle greenhouse gas emissions associated with the built environment (including both commercial and residential buildings) is rising up the Government’s agenda: the package of measures being put forward and envisaged in the new strategies and their associated consultations delivers on commitments made in the Government’s Ten Point Plan and for a Green Industrial Revolution and Energy White Paper. 

Just before Christmas, the Government announced changes to the building regulations that mark a bold step in the direction of delivering net zero. The changes have not yet taken effect and do not come into force until Wednesday 15th June this year. 

In brief, the regulations that amend the Building Regulations 2010:

• make provision for a new way of measuring energy efficiency that utilise a new performance metric
• change the way on-site electricity generation systems are regulated
• introduce regulation on overheating mitigation
• make provision about ventilation standards when work to which Part L (conservation of fuel and power) applies
• include the necessary associated changes to the Building (Approved Inspectors etc.) Regulations 2010
• include transitional provisions and
• make minor changes in respect of self-certification schemes.

In January last year, the Government published the outcome of the Future Homes Standard consultation which sought views on the changes that needed to be made to Parts L (conservation of fuel and power) and F (ventilation) of the Building Regulations in order to improve the energy efficiency of new homes. 

The Building Regulations changes include a requirement for new homes to produce around 30% less CO2 than current standards, and a 27% reduction in emissions from other new buildings. The measures represent an ‘interim uplift’ in energy efficiency expected in buildings, ahead of stricter rules – named the Future Homes Standard and Future Buildings Standard – being introduced in 2025. The new Future Homes Standard should ensure that all new homes built from 2025 will produce 75-80% less carbon emissions than homes completed under current regulations.

All new residential buildings, including homes, care homes, student accommodation and children's homes, must also be designed to reduce overheating. Improvements to ventilation are also being introduced to support the safety of residents in newly-built homes and to prevent the spread of airborne viruses in new non-residential buildings.

Alongside amendments to the Building Regulations, 5 new Approved Documents were published:

• Approved Document L, volume 1: dwellings
• Approved Document L, volume 2: buildings other than dwellings
• Approved Document F, volume 1: dwellings
• Approved Document F, volume 2: buildings other than dwellings
• Approved Document O covering overheating.

The technical scope of the amendments is not set out within this article. However, to give an example and convey a sense of the detail, new Approved Document O stipulates that buildings in London with cross-ventilation will only be allowed a glazed area over 15% of the north and south façades and 18% for the east and west facades. In addition, the maximum area of glazing in the most glazed room of the building is to be 37%, but only 22% if the room is south facing. If a building does not have any cross ventilation then the maximum area of glazing could be as little as 11%. Residential buildings in high risk locations (such as London) will also need to provide shading for glazed areas between compass points north-east and north-west via the south – either external shutters with means of ventilation (and glazing with a maximum g-value of 0.4 and a minimum light transmittance of 0.7), or overhangs with 50 degrees altitude cut-off on due south facing facades only.

The new Approved Document O will have a significant impact on property owners, developers and social housing providers. The interim measures will apply to all projects from 15 June 2022, except where a building notice has been given or full plans have been submitted with local councils (in which case work on the building can continue under the previous standards). The updated regulations will, however, apply to all projects regardless from 15 June 2023. Architects and engineers have criticised the government’s amendments to energy efficiency regulations as not going far enough. However, it is going to introduce additional costs to leaseholders in this unprecedented time where they are already potentially trying to meet the cost of the fire safety remedial work. 

In addition, a second and separate set of amendment regulations to the Building Regulations provide from June 2022 that infrastructure for the charging of electric vehicles has to be installed when:

• a new residential building is built with associated parking
• one or more dwellings with associated parking results from a building undergoing a material change of use
• a residential building undergoing major renovation has more than 10 associated parking spaces following the renovation
• new buildings, which are not residential or mixed-use, have more than 10 parking spaces; or
• a building, which is not residential or mixed-use, undergoing major renovation will have more than 10 parking spaces after the renovation is complete.

The amendments contain specific detail concerning how many charging points have to be provided in such cases. To support this second set of amendments, the Government has published Approved Document S on the infrastructure for the charging of electric vehicles (which is a new Approved Document).

Procurement teams around the UK need to consider the impact of these amendments on any upcoming projects. Compliance teams will only have to review their current property portfolio to ascertain what works will be required to meeting the new building regulations. In light of this, employers will need to ensure that their contracts and the wording within their development agreements and building contracts capture the changes in regulations.