New Part L & F Consultation

Following months of speculation after the release of SAP 10.0 the Government has published the first of two Approved Document L (conservation of fuel and power) consultations and the BRE has published SAP 10.1. The release of these consultations has been anticipated for some time, introducing plans for a significant improvement in carbon dioxide emissions over current standards as well as including changes to Part F (Ventilation), air tightness and improving the ‘as built’ performance of the constructed home.

Energy efficiency requirements

In response to the new UK law which targets to bring all greenhouse gas emissions to net zero by 2050, the proposed draft Approved Document aims to provide the roadmap to future energy standards. Two options are being discussed on how to meet this target. The preferred approach is a 31% reduction in carbon emissions when compared to current standards (option 2), with the second approach suggesting a less demanding 20% reduction (option 1). These are considered to be stepping stones to the 75-80% reduction targets in the Future of Housing Consultation. Each option is provided with a potential specification in order to meet these requirements but is clear that a wide variety of approaches to meet these performance targets are expected.

Transitional phase

In the past new Building Regulation changes have taken time to be adopted, typically with a year grace period, and in some instances with phased developments able to use old Regulations for future phases.  To mitigate this, the consultation is proposing to encourage a quicker implementation of the new energy requirements, where any specific building yet to have any work commenced is to be built to the latest standards. The introduction of this stricter implementation may result in sites with the same planning consent being constructed to different Building Regulations.

Performance metrics

The new Part L is proposing four performance metrics for buildings to be measured against, which are as follows:

  • Primary energy target
  • Carbon dioxide emission target
  • Householder affordability rating
  • Minimum standards for fabric and fixed building services

It is proposed that primary energy will be the principal performance metric and carbon dioxide emissions will be used as a secondary metric. This would measure the total energy demand of the building, accounting for the whole heating fuel Lifecyle rather than just the heat demand of the dwelling.

The currently used fabric energy efficiency metric has been removed, with the proposal to encourage good fabric by retaining and improving the minimum standards for the individual fabric elements (walls, roofs, floors, windows etc).

Electric heating

The latest CO2 emission factors released by the BRE in SAP10.1 considers electricity to be less carbon intensive than gas. In combination with the proposed removal of fuel factors this allows electric heating to become more appealing. However, the new Approved Document is careful to note electric heaters are very expensive to run, and if introduced on a large scale it may have a significant impact on the National Grid.

To address the above issue, there is the proposal for the introduction of the householder affordability rating to reduce the risk of high energy bills for consumers, which will be based on the theoretical energy cost of the dwelling. As a result of the lower fuel factors for electricity, heat pump technologies are looking more promising as they have the same low-carbon benefits as direct electric heating, but can deliver heat much more efficiently overcoming affordability issues and grid-resource constraints.

Phasing out high-carbon fossil fuels

It is the Government’s intention to phase out high-carbon fossil fuels in new build housing developments by 2025 with the new Part L supporting this intention. The removal of fuel factors will no longer provide any relief to the high-carbon heating systems like LPG and oil, which was previously introduced to help developments that did not have access to mains gas. The new Part L does not look to ban these heating systems but it will make it considerably more difficult to comply with substantial mitigating measures being required.

Energy planning requirements

The draft Approved Document proposes to streamline the planning process to potentially prevent Local planning authorities from having the power to set their own energy efficiency standards in an effort to avoid confusion and inconsistencies across the country. The move to the higher energy standards required by the new Part L may lead to the Planning and Energy Act 2008 becoming amended or even made redundant.

Overheating

Following the 2018 Environmental Audit Committee it was recommended that the Government should create a new regulation to stop buildings being built which are prone to overheating. In response the Government is committed to consult around introducing a new overheating standard in an effort to manage internal temperatures but the details are yet to be released.  If you want to find out more about the risk of overheating we recently published an article about this on our website http://aessc.co.uk/blog/overheating/

Air testing

Consideration is being given as to whether developers should test all individual homes on a development instead of having the option to sample test, to avoid the potential of untested dwellings not meeting the required standard. Developers will also need to include all failed air tests within the pack of documents submitted to Building Control to indicate remedial works have been completed.

The air tightness testing scheme methodology is under review and consideration is being given to alternative testing methods such as a pulse test. The proposed new minimum standards for fabric performance for air permeability is being lowered from 10 to 8m3/m2.K at 50Pa.

Air quality

The proposed Part F changes will look to include mandatory opening restrictions on buildings in low air quality areas in an effort to promote healthy indoor air quality in new homes. Consideration is also being given to the noise output of ventilation installations as research has shown this to be one of the factors contributing to home owners turning off fans, resulting in poor air quality. The draft Approved Document is clear that systems should not be unduly noisy but further consideration may be given in a future Part E consultation.

Consultation

Currently this consultation relates only to the Building Regulations for England, which will remain open for comment until the 10th January 2020. If you wish to respond, please see the online survey at https://www.surveymonkey.co.uk/r/TQW8GQ9. The Government has released a preferred option in relation to timings with the proposal of mid/late 2020 for the new regulations to come into force. It is expected in the near future for Welsh Building Regulations to also go out for consultation.

We are still reviewing all the proposed changes and further articles will be released over the coming months to keep you up to date and assist you in preparing for the new Regulations.  Feel free to get in touch with us if you want any further information on this in the meantime at info@aessc.co.uk

Proposed Timetable

Late 2019 / early 2020

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

Early / mid 2020

Publication of new Part L, Part F and overheating regulations, associated guidance and supporting analysed consultation response documents.

Mid / late 2020

Part L, Part F and overheating regulations come into force.

Further Links

Future homes standard:

https://www.gov.uk/government/consultations/the-future-homes-standard-changes-to-part-l-and-part-f-of-the-building-regulations-for-new-dwellings

Draft Part L and F:

https://www.gov.uk/government/publications/building-regulations-approved-documents-l-and-f-consultation-version

SAP 10.1:

https://www.bregroup.com/sap/sap10/