VOICES | JULIE GODEFROY Whats the plan? Julie Godefroy I n late January, the government published a long-awaited consultation package on Building Regulations, covering: new and existing dwellings and non-domestic buildings; 2021 Approved Documents L and F; a new overheating standard for new homes; and outlines of the 2025 Future Homes Standard (FHS) and Future Buildings Standard (FBS). There are some positive changes in the proposals, compared with the 2019-20 FHS consultation: Retaining the right of local authorities to set energy and carbon standards beyond regulatory minima, allowing more carbon savings earlier, and developing the rest of the market Accelerated development of the FHS, with a draft now due in 2023. This will allow early adoption by market leaders and local authorities, and support the development of supply chains. There is little evidence that NCM drives improvements on nondomestic buildings standards (FEES), the removal of which created serious risks of fuel poverty and poor fabric performance For non-domestic buildings, clear statements acknowledging the performance gap, with a strengthening of commissioning requirements, changes to the NCM to better account for energy uses and incentivise appropriate design solutions, and energy performance modelling (for example, CIBSE TM54) for buildings of more than 1,000m2 For non-domestic buildings, clear statements about the importance of heat decarbonisation, anticipating a central role for heat pumps and no role for hydrogen in the timescale considered. However, there are many concerning measures and omissions, which could be addressed by the following key asks (with implementation date in brackets): 1. Target setting: the consultation retains the approach DR JULIE GODEFROY is technical manager at CIBSE based on a notional building. All opportunities need to be captured towards the net-zero carbon target. The notional building prevents like-for-like comparisons and does not drive optimisation of building form and orientation. New buildings of the same type should be compared with the same target level of performance. (2025) For non-domestic buildings, the 2021 uplift proposes to vary the heating fuel in the notional building for example, district heating or gas if this is in the actual building. This gives artificial support factors for particular systems, rather than a like-for-like evaluation of low carbon options. (2025) 2. Metrics: the consultation proposes a dual-metric system primary energy and carbon alongside a fabric performance requirement. Neither metric means much to consumers, especially primary energy. They rely on conversion factors, which change over time, and this does not facilitate tracking of progress, comparing buildings, or creating a closer link with actual performance. Also, primary energy favours gas over electricity, so goes against heat decarbonisation. Energy use and carbon would better address energy efficiency, carbon reduction, and consumer engagement. (2021) 3. A commitment to actual performance, starting with disclosure: actual in-use performance beyond practical completion must be addressed for example, as part of the regulatory regime created in response to the Hackitt Review. This should start with disclosure of energy use (broken down into fuels where applicable). (2021) The data could inform future revisions of Building Regulations and the setting of absolute, not relative, targets (see point 1). (2025) 4. Commissioning: there should be stronger incentives for commissioning and performance testing, such as a penalty in as-built Part L calculations unless satisfactory results are given to Building Control. This will benefit energy efficiency and, for ventilation, air quality. (2021) 5. Airtightness and ventilation: the draft FHS specification proposes an airtightness of 5m3.h-1.m-2 at 50Pa, and natural ventilation. This is far from the world class levels of energy efficiency intended for the FHS, and is a remaining important opportunity for energy savings. The FHS specification should show best-practice airtightness and MVHR (even if other systems remain allowed). This would encourage the development of supply chains so that MVHR is well designed and installed, and delivers energy savings and good indoor air quality. (2025) 6. A trajectory for existing stock: for existing domestic and non-domestic buildings, the consultation package only includes a 2021 revision, and it is a relatively modest one. Government must commit to a 2025 upgrade and set out a programme of works to introduce upgraded requirements informed by evidence, and supported by clear guidance on complex technical issues. This should incorporate lessons from recent exemplar retrofit projects, 16 April 2021 www.cibsejournal.com CIBSE April 21 pp16-17 Julie Godefroy.indd 16 26/03/2021 14:36