In November 2023 the AJ featured an article written by our Director, Richard Hawkes, which discussed how EPC certificates had transformed the design and efficiency of domestic appliances and looked at award winning houses to see if a similar trend could be seen in the energy ratings of houses since EPCs were introduced.

In 1992 energy ratings much like Energy Performance Certificates kickstarted a transformation in the way we design our domestic white goods.

Over more than 25 years, the A-G colour coded ratings with which we have become familiar were extended to include A+, A++ and A+++ as appliances increasingly improved their energy efficiency. This congestion at the top of the ratings was making it difficult for the consumer to understand.

In response to the efficiency revolution the ratings were recalibrated in 2021. So, a fridge which achieved an A+ rating pre-2021 is now an ‘F’ under the new ratings.

This doesn’t, all of a sudden, make the fridge bad. But it demonstrates how far we’ve come in the way we design the appliances we so depend upon.

I couldn’t help but wonder whether we’re seeing the same trend in the way we build, recognise and reward energy efficiency in the design of new houses.

In 2008 Energy Performance Certificates were introduced as part of a EU initiative to drive improvements in the energy efficiency of our homes. Around the same time, the Code for Sustainable Homes (CfSH) was introduced. It charted a roadmap that would have led to all homes being delivered to ‘zero carbon’ standards by 2016.

In 2014 the Building Regulations, particularly AD Part L, were updated. The low bar set by these regulations would remain in place until a much-needed and long overdue update in 2021.

In 2015 the government withdrew the CfSH, setting back the Road to Zero.

As an architectural practice specialising in the design of houses of exceptional quality in the countryside, otherwise known as Paragraph 80 houses (‘the Country House Clause’), our work is often measured against a higher bar. This unique planning policy exception in the NPPF requires proposals to be ‘truly outstanding and reflecting the highest standards in architecture’.

In 2021, in an effort to somehow ‘objectify’ what ‘the highest standards in architecture’ means, we published the EPC certificates of the houses which had been longlisted for the RIBA House of the Year, which had been elevated to a prime-time TV series just after the COP26 climate conference.

The results were surprising. Only one of the 16 longlisted houses had achieved an ‘A’ rating and the winning project that year did not even have an up-to-date EPC certificate. The average was a surprisingly low ‘C’ rating. The national average house has a ‘D’ rating.

Is this representative of ‘the highest standards in architecture’? And does it seem consistent with the ‘climate-conscious trajectory’ enshrined in the targets set within the RIBA 2030 Challenge?

Some lazy justification by the chair of judges in an AJ article in December 2021 on the subject was revealing. Subsequent interest in the relationship between award-winning projects and their energy efficiency led to a more extensive look back to see whether any upward trend could be seen in projects judged to be able to sit at the top table.

Our research looked back to all RIBA House of the Year shortlisted projects since 2011 – a three-year ‘grace period’ after EPCs had been introduced.

Disappointingly, the average EPC and Standard Assessment Procedure (SAP) scores of shortlisted projects between 2011 and 2021 remained at a less-than-inspiring ‘C’ rating.

A slight improvement in 2022 edged the average into a low ‘B’ rating, but the winning project achieving a lacklustre ‘C’-rated EPC.

This year’s House of the Year showed promise in having five ‘A’-rated houses on the 2023 longlist. Sadly, only one of those has made it onto this year’s shortlist of six projects, which still includes two projects which don’t have an EPC certificate and another ‘C’-rated scheme. The average shows no progress from 2022.

On a positive note, at least with publicly visible tools which illustrate operational energy, EPCs and the SAP are enabling a discussion to be had. Measuring the embodied carbon, especially on smaller projects such as individual houses is important, but difficult to do accurately.

So do the EPC ratings of the House of the Year 2023 shortlist really reflect the climate conscious trajectory set by the RIBA in its 2030 Climate Challenge?

Are these six homes truly representing ‘the highest standards in architecture’ in a climate-aware 2023? Or, unlike the transformation in the way we build fridges, is the House of the Year award and the homes it champions still frozen in time?