TWO EXPERTS: ONE BELIEVER - ONE SCEPTIC
The X files:
Does certification truly deliver?
I’d argue that, in many ways, a building’s owner and occupants don’t necessarily experience much benefit from a high-scoring certification rating.
Most certification schemes focus on the design elements and are awarded around the time of practical completion or handover. Often, the aspects of a rating system that affect a building’s energy demand, emissions, and internal environment are based on predictive calculations with no mandated post-occupancy verification to check that these predictions were achieved. To me, certification doesn’t do enough to overcome the now fairly well understood ‘performance gap’ issue.
A Better Buildings Partnership analysis of the energy-use in more than 200 properties showed that there is little or no correlation between EPC ratings and actual energy performance. In fact, the average energy consumption of
a building was found to be similar whether the building had an EPC rating of C, D or E.
Have designers and assessors become increasingly focussed on achieving the necessary points rather than a useful outcome? If certification is treated as a tick-box, point-scoring exercise then it won’t deliver better buildings. From the occupant’s perspective, their building’s certifications are probably deemed somewhat irrelevant.
I believe, if we want to deliver better buildings that perform as well as we intend at design stage, we have to bite the bullet and commit to verifying that in-use performance is in line with our design estimates. Where it’s not, there may be some simple adjustments that can be made through a seasonal commissioning process to reduce the performance gap. It would also allow designers to learn more about the reasons for differences between design and operational performance, and would lead to better designs in the future.
Emerging delivery frameworks, such as WELL and Design for Performance, focus more on post-occupancy performance and therefore guarantee better outcomes alongside a shiny certificate. I believe they signpost the future direction that certification schemes must head in to remain relevant.
Often the flexibility of certification schemes can lead to a perception problem from clients and design team members. Good-practice features incorporated into designs don’t necessarily make the building more sustainable, but rather offer the potential for them to be so. For example, unused cycle racks don’t improve the sustainability of a scheme, but no cycle racks at all would completely remove the option for occupants to safely secure their bikes, and is likely to discourage sustainable travel.
As technically-minded professionals, it’s natural for us to base our measure of success on empirical information or that which can be measured and demonstrated. In buildings this often draws us to energy performance and it is here that faith in certification’s ability to deliver can be doubted. However, the very point of certification is to cover a wide range of themes. Take BREEAM for example: it ensures that no key sustainability themes are ignored and that the benefits of one part of the tapestry of sustainable environmental factors are not over sold. For instance, you might have an energy-efficient building but you’ve chopped down woodland to build it, or you have a WELL Gold building but it’s difficult to get to and workers experience
a long, stressful commute.
Often, frustration with certification is generally due to the procedural and bureaucratic nature of schemes and not due to their elements being poorly thought out or irrelevant.
It’s also crucially important to consider that most certification schemes are regularly updated and therefore can incorporate improved approaches, such as Design for Performance. With this is in mind, in the future I believe certification schemes will evolve to include better metrics, and continue to be a mechanism to drive improved environmental performance.