A large majority, prominent public concern about the environment, and cross-party support for the Climate Change Act: the new government has no excuse for inaction towards net-zero carbon. With the UN Conference of the Parties (COP) due in Glasgow in late 2020, it also has the perfect incentive and opportunity to show leadership.
This should start with substantially amending the consultation proposals for Part L 2020 and the Future Homes Standard, which currently fall well short.
The proposed carbon reductions (20% and 31% options) and fabric efficiency requirements mean we could still be building new homes that will later need fabric retrofitting, at much greater disruption and cost to the owners. The no-regrets option is the most efficient fabric possible for new buildings, alongside consideration of air quality and overheating.
The notional building is currently proposed to have a gas boiler. This does not send a strong signal to transition away from gas. More importantly, because electricity has a lower carbon factor than gas under the new draft SAP, a Part L 2020-compliant dwelling with direct electric heating could have worse fabric performance than under Part L 2013. This is clearly a step in the wrong direction, and raises concerns about peak electricity demand and fuel poverty.
The proposal to omit the Fabric Energy Efficiency Standard (Fees) could not only lead to relaxed performance of individual fabric elements, but also remove the incentive to consider building form, the first step of passive design.
We need compliance metrics that relate to building performance itself. Compliance is currently based on ‘two-system’ metrics – carbon emissions and primary energy. Ultimately, it should relate to metered energy to directly reflect building performance and better connect with householders; carbon emissions should remain as the other compliance metric, possibly supplemented by heating demand (for example Fees, or similar).
Government needs to establish a clear trajectory towards in-use performance requirements
The Future Homes Standard should be available much earlier than the proposed 2024. It could then be adopted by leaders from local authorities and industry, an essential step before widespread implementation. A key learning area is to achieve better standards of airtightness and ventilation installations, to deliver carbon savings without detriment to health and wellbeing.
Local authorities should be allowed to set requirements beyond minimum regulations, subject to the usual viability testing. This is another important way to build expertise and supply chains. The current proposed ban would be a significant brake on carbon reductions, and a backward step for some local authorities, such as London.
Government needs to establish a clear trajectory towards in-use performance requirements covering all energy uses, starting in 2020 with a requirement for disclosure of performance. This could be done on an aggregate basis for schemes above a certain number of dwellings, to protect privacy and reflect building performance trends independently from the behaviour of individual householders.
These are no doubt challenging, in particular the shift to in-use performance and total energy use. However, this is in line with the task of achieving net-zero carbon. Of course, in-use performance is not currently covered by Building Regulations, and only in a very limited way by the Energy Performance of Buildings Regulations (through Display Energy Certificates and air conditioning inspections). A framework would be needed to safeguard privacy, define responsibilities, set procedures for reporting and enforcement and all of this will probably require changes to primary legislation.
So what? Mr Johnson certainly has not seemed overly constrained by existing regulations so far. By comparison with his government’s rumoured ambitions for reforming the civil service and the House of Lords, or revoking the Fixed Terms Parliament Act, a change – such as amending the Building Act – shouldn’t be an insurmountable challenge.
You can support the CIBSE response to the Part L and Future Homes consultation. A huge thanks to all who have already sent thoughts and supporting material. The response deadline has been extended to 7 February, so keep sending us contributions. We are particularly interested in SAP sensitivity analysis and in-use performance data (this can be anonymous). For full details, see the CIBSE consultation page.
- Submit your own response: A current draft of the CIBSE response is available on the CIBSE consultation page, as an example.
- Support the Building Performance Network joint statement on operational performance, signed by CIBSE and other organisations.
Dr Julie Godefroy is technical manager at CIBSE