The Future Homes Standard Consultation – Technical Briefing
The attached is a briefing note to make you aware (if not already) about the major changes in the offing in respect of energy conservation in buildings and ventilation. The MHCLG aims to introduce the Future Homes Standard by 2025. This is a stepping stone towards the further target of net-zero greenhouse gas emissions by 2050.
New and existing homes produce around 20% of all carbon emissions in the UK. As part of the efforts to meet the UK’s ambitious target to reduce greenhouse gas emissions to ‘net-zero’ by 2050, the government has committed to introducing what they are calling the ‘Future Homes Standard’ in 2025. This anticipates that an average home will have 75-80% fewer carbon emissions than a home constructed to the current national standards for energy efficiency. Their plan is to realise this by introducing very high fabric efficiency standards combined with low carbon heating systems.
As a transitional stepping stone towards that target, the Government launched a Future Homes Standard consultation at the end of 2019. This considers options for uplifting standards in Approved Document L1 covering energy efficiency in dwellings that will come into force sometime in 2020. Being aware of the sensitive interaction between energy efficiency, airtightness, and healthy ventilation standards, this is accompanied by proposals to revise Part F (Ventilation) and its associated Approved Document. The consultation covers buildings in England and runs until an extended deadline of 7 February 2020.
Proposals for changes to Part L2 covering non-domestic buildings are also in the pipeline but not yet published and so far the current proposals are limited to new buildings with alterations or extensions to existing buildings being covered in a future consultation. With recent research on ventilation clearly showing the potential for overheating in homes built to current standards, focus will also be given to the prevention of such issues.
A welcome initiative in the consultation is the clarification of the role of planning authorities; removing their ability to set higher energy efficiency standards than those in the Building Regulations.
Summary of Changes to F and L
There are 2 options to uplift Part L that are described in the consultation; a 20% reduction in carbon emissions, achieved through better fabric only or a 31% reduction achieved with carbon saving technology and fabric improvements. The latter option is more expensive to achieve but is the preferred government option. It is proposed that information in the formerly separate domestic services compliance guides be incorporated into the Approved Document and that L1A (new buildings) and L1B (alterations to existing buildings) be incorporated into a single volume 1 document covering dwellings.
Proposed changes to Part F include a simplification of the method of determining the ventilation rate and system design for new build homes. There are also efforts to simplify the presentation of guidance in the document for more easy navigation, For the first time, recent research into air quality considerations has prompted proposals for dealing with health risks from external pollutants.
A more detailed summary of the proposed changes is appended below.
Believing that tighter rules on the transition to the new requirements are justified to fast track implementation, the Government proposes to change transitional arrangements so that builders cannot lodge applications for large developments early, in an attempt to lock in earlier standards for energy efficiency. This is covered in Chapter 7 of the consultation and the idea that permission should lapse on individual buildings not commenced within a certain (unspecified) period has been mooted.
Government’s preferred option on timing
Subsequent consultation on:
Overheating in new dwellings
Energy efficiency standards for work carried out in existing dwellings
Energy efficiency standards for new buildings other than dwellings
Energy efficiency standards for work to existing buildings other than dwellings
Publication of new Part L, Part F and overheating regulations, associated guidance and supporting analysed consultation response document.
Part L, Part F, and overheating regulations come into force.
Beyond 2020 Below is a roadmap included in the consultation document showing proposals through to 2025. At this point, further uplift is expected to form another stepping stone towards meeting the ambition for net-zero carbon in 2050.
Summary of Proposed Changes
Chapter 3 Covering changes to Part L and Part 6 of the Building Regulations
Changing the whole building minimum energy performance target by:
introducing primary energy as the principal performance metric, and continuing to use a CO2 as a secondary metric
removing the fabric energy efficiency metric
incorporating the latest evidence on primary energy and CO2 emissions of fuels, and removing fuel factors in the calculation for high-carbon fossil fuels and electricity
introducing a householder affordability standard for new dwellings, so that new homes are affordable to heat. This is intended to prevent developers from adopting low-cost compliant design solutions that burden owners and occupiers with higher running costs. Taking a significant interim step towards the 2025 Future Homes Standard through:
uplifting the minimum standard of whole-building energy performance
improving the minimum insulation standards
improving the minimum efficiencies of fixed building services
future-proofing new dwellings to be ready for low carbon heating systems
improving compliance with Part L in order to improve as-built performance
aligning the Part L standards for new dwellings with the 2018 revisions to the Energy Performance of Buildings Directive, where relevant
adopting the most recent version of the government’s Standard Assessment Procedure for Energy Rating of Dwellings Version 10 (SAP10.1)
Chapter 4 Covering changes to Part F
simplifying the approach for determining the ventilation rate and system design requirements for a dwelling
reviewing the way that ventilation systems are presented in the Approved Document to reflect common design practices
bringing guidance designed to reduce the ingress of external air pollutants into the main body of the Approved Document, and reviewing its technical content
making technical changes to guidance for ventilation systems in line with the latest evidence and understanding
simplifying the structure and content of guidance relating to Part F
Chapter 5 Covering changes to the airtightness requirements of Part L
reviewing the approved airtightness testing scheme methodology
considering whether developers should test all individual homes on a development, and removing the option of sample-testing
limiting incentives in SAP which encourage very airtight naturally ventilated dwellings
reflecting the uncertainty of air permeability test results in SAP
exploring the potential for alternative testing methods or alternative approaches to demonstrating compliance with guidance on airtightness
Chapter 6 Covering proposals for improving compliance performance and providing information
providing guidance notes to improve build quality and reduce the performance gap. These would give practical advice on how builders could address the performance gap and reduce thermal bridging while ensuring airtightness doesn’t harm the structure of the building
developing a new style Part L compliance report
Improving the accuracy of as-built energy models by proposing photographic evidence for new dwellings
educating building occupiers on how to operate low-carbon homes by proposing home user guides for new dwellings
We will be providing customer training once the new Approved Documents are finalised. Please subscribe to our communications here to ensure you don’t miss our invitations to both this and further CPD events.