The construction industry should put more effort into learning from its mistakes in order to create better, more efficient buildings in future, with greater emphasis on buildings in use than the often ‘tick-box’ approach behind various environmental certification tools.

That was one of the key take-aways to emerge from a Think Tank held at the offices of Hoare Lea, entitled Improving sustainable performance: sticks, carrots and nudges.

UKGBC senior technical advisor Anna Surgenor began by saying that in 25 years, the number of rating tools and breadth of building types they apply to has been expanding, playing a part in influencing the built environment and government specification. But they can be seen to be ‘restrictive, burdensome, time-consuming and sometimes costly too’, she said. Although they are here to stay and provide independent assurance, frustration often arises when a lot of the specification is done during the design phase, but when it comes to operation – when people are in the building and the ‘machine’ is running – it doesn’t quite stack up. Members are keen to set up a forum to share best practice in this area, said Surgenor. 

The BRE, said Tim Wiseman, wants to get people to use BREEAM voluntarily and believes that the system is helping to drive standards forward. But has it performed as the industry expected? ‘I believe in general the standards are going higher in the last 25 years or so’, said Wiseman, with the next challenge likely to be in the housing standards review and consumer-focused standards.

Only now is BREAM starting to look at energy in use, and even then not compulsorily. ‘Unless you are focused on energy in use both at the design stage where you’re predicting, and at the in-use side of it trying to get the building to work properly, you won’t crack that’, said Fogarty.

Ratings tools do at least enable a conversation at concept stage about sustainability that wouldn’t otherwise have happened, said Ashley Bateson, partner at Hoare Lea. But we cannot always monetise those benefits and it is certainly not a guarantee of a well-run building, even if, as Bennetts Associates architect Ben Hopkins pointed out, it has not raised the top of the market as much as it has the bottom. Sometimes BREEAM actually precludes a good building, said AHMM head of sustainability Craig Robertson, because it ‘disaggregates’ the thinking and the process. It has to get better at linking process to outcome; too often people are allowed to simply assemble credits without thinking of the composite whole, he said. Some design teams approach BREEAM purely as a tick box, preventing people from engaging, added Fogarty.

There is a ‘huge performance gap’, said PDP London partner Marion Baelli, in the modelling stages of buildings, but Passivhaus has turned much of this on its head, , with a proven and broader, more diverse sustainable approach. 

For all of this ‘dissing’ of assessment methods though, said Bateson, when Hoare Lea does post-construction reviews it was easy to recognise the good things that assessment methods have done. In schools this could be ensuring more robust materials are installed, in residences that appliances and lighting is checked, and in offices, that, say, low-VOC paints and natural materials are used. When the government reduced support for the Code for Sustainable Homes, for example, it was noticeable how much that reduced quality. 

Rating tools, then, are not perfect, and the kind of sustainable ‘gurus’ around the table would make buildings work environmentally without it, said Surgenor. The problem is that the reality out there is that people in the wider profession need a level baseline to get them to be ‘remotely sustainable’, and without rating tools and standards we would be at a low point.

Maybe it would be useful for the UK to develop similar to the commitment made by the AIA, said HOK head of sustainability Joyce Chan, where companies sign up to a 2030 commitment on energy intensity per square metre.  The kilowatt hour per m2 unit is so key to the assessment of a building, agreed Baeli. The kilowatt hour per hour worked might be an even more useful measure, said Fogarty, because that would show how hard the building is working relative to the time of the day.  But the industry is full of ‘dinosaurs’ in terms of the sheer amount of overheating, underperforming schools and other buildings that are constructed, said Fogarty. ‘Having minimum standards would be essential because that is what most people design to’.

BREEAM is now a core requirement for most customers – they expect it, said Landsec Sustainability Insights Director Edward Dixon. ‘it’s just the same as having superloos or having LED lighting’, he said, rather than something to target or achieve. It is an expected part of the specification; we need passionate people but part of the problem is that certification tools have been the main part of the conversation, rather than giving reasons to come to the design team to ask difficult questions over accessibility, wellbeing, productivity, how much the energy bills will be for each occupier. This lifts the design team, said Dixon, and has made an ‘enormous difference’ by shifting the purpose from certification alone. But that works with an educated client that knows what good looks like, said Overbury head of sustainability Joe Croft. 

But one of the key issues is the amount of ‘stuff’ we put into buildings now, said Dixon, which is adversely affecting energy intensity, and will mean that certification and post-occupancy evaluations will be checking, yes, but will likely only be finding that we simply have more energy intensive buildings. For climate change issues, however, the number one topic that needs to be better addressed must be targeting existing buildings, said Marion Baeli. 

We must not be lazy about design, however, said Levitt Bernstein head of sustainability Clare Murray, in creating buildings that need more energy and intensity. BREEAM sets the standard but allows us to forget why we’re setting building parameters that we do – Passivhaus has much more wall to window ratios, for example. 

But another key issue is education, said Elementa associate principal Nathan Miller, with the need to talk about what works and doesn’t, sharing expertise across the industry about how buildings operate. The new London Plan’s energy policies state that you need to show how you demonstrate carbon neutrality. Another shift is toward wellbeing, with Matthew Ryan’s organisation Cadogan looking to a cut-down, bespoke and perhaps more cost-effective version of Passivhaus, while Fogarty suggested that the system does have a propensity to overheating, something that its software is being modified to correct in the UK

Levitt Bernstein carries out post-occupancy evaluation on its buildings, said Clare Murray, but it doesn’t require the permission of the client, nor often residents. Nobody wants to pay for it, and people are also worried about the prospective results, so it is useful internally to learn from lessons, but that does not get shared, partly for legal, contractual reasons, and insurers tend to advise against it. ‘There are lots of barriers that tend to get in the way’, she said, but the people who want to do them and do it the best are those clients and design teams who want the best for their building and are willing to learn from mistakes. The barriers are a tough nut to crack, but should be overcome by sharing more, perhaps starting with a case study of a scheme that worked well but had some bad points. 

Bennetts Associates publish academic papers and talks in this area, said Hopkins, but perhaps projects can be anonymised. Awards are another positive trend towards rewarding high performing buildings, CIBSE running a performance award for one, said Bateson. The BCO has a test of time award, and perhaps we need a test of the last 10 Stirling Prize winners to see how they measure up. ‘Some of the institutions are going towards it and there’s nudging at the mayor’s office in terms of assessing buildings that might come in a further iteration of the London Plan. But demonstrating that you’ve learned from buildings is crucial for repeat business with clients.’ For PoE to be really useful, said Dixon, it should not be considered an end of project item but one where designers are asked what they have learned from their other projects. The fee structure should be rejigged to take this process into account too, said Chan. Post occupancy evaluation has been wrapped up in sustainability, said Robertson, but really it was about how good buildings are across every possible metric. ‘It’s a quality assurance thing.’ 

When they get above a certain level, people in the office now get a buzz on their app, he explained, and the facilities manager is called, usually to investigate a failed vent or similar. So the future may be about more wellbeing-orientated readings. And perhaps a more Utopian future was presented by Fogarty concerning better air quality – of getting cars off the road, more use of public transport, less roads and more green, and more natural ventilation. The London Plan’s healthy streets ideas go some way towards this – but perhaps not far enough.