The American engineering professor Robert H Socolow once stated that the observed variation in energy consumption for space heating in townhouses with identical floor plans, furnaces and appliances is primarily assignable to the resident rather than to structural features that persist independent of the resident.
He pointed to studies on houses where there has been a change of owner and new occupants exhibited consumption levels that bore almost no relation to their predecessors.
You’d be wrong in thinking that the situation had been resolved in the 32 years since that statement. Take, for example, a 2010 study of a low-energy domestic site in the UK, which showed up to seven times variation between the resource consumption of comparable dwellings.
Unexpected performance outcomes persist across all building sectors while the management and operation of more complex buildings, such as in the commercial and public sector, has a significant impact on real-life performance - and simple changes such as a new facilities manager can result in vastly different resource consumption.
User behaviour is to building performance what carbon emissions are to climate change: a root cause that now requires thorough understanding and management to avoid potential system failures.
Deep-seated sustainability will not prevail without continued understanding of users and their behaviours.However, that is not to say users are malicious in their resource consumption nor their utilisation of buildings.
They merely strive to be comfortable and satisfied within their environments and users cannot be expected to make exhaustive efforts to minimise consumption levels - certainly not if the methods to do so are complicated and poorly explained or if useful information founded on evidence and feedback is not readily available to them.
The efficacy of behavioural change measures are promising though: building studies regularly show that five to 15 per cent savings can be achieved through the provision of sound advice and live feedback on consumption - and more if community-scale measures are adopted.
Communities such as Ashton Hayes are even working collectively and independently towards making a lower environmental impact, with great success.
So, what might be done to consistently maximise efficient user behaviour in buildings? Well, there are no silver bullets but here are some pointers that should be considered:
- Facilitate efficient operation: smart metering, live feedback on consumption, good controls design, etc. We need to provide users with the tools and information they require to efficiently operate their building.
- Induction: don’t expect users to understand how best to use a new building from the get-go, especially if no training or advice is given from initial occupancy. Approaches such as Soft-Landings provide a framework for assisting occupants.
- Champion efficiency: highest performing buildings are often found to have a responsible and enthusiastic ‘champion’ working to operate the building efficiently and make improvements. On a domestic level this relationship between users and consumption is clear, but for complex buildings the importance of even a single ‘champion’ should not be underestimated.
- Points of reference: is it sufficient to only make a 10 per cent reduction on a building that uses twice the norm? Benchmark comparison to similar buildings means that the excessive users have most incentive and reason to reduce. The Carbon Reduction Commitment League Table is an example of making comparative performance information more transparent.
- Manage ‘take-back’: some studies counterintuitively show increased resource consumption following installation of energy efficiency measures/technologies - also known as the ‘rebound’ or ‘snackwell’ effect. Some of the above points can help with reducing the impact of ‘take-back’.
- Reduce unmanageable complexity: training, information and advice are all well and good, but if the building systems simply cannot be operated efficiently in conjunction with each other then efforts will be in vain.
- Don’t miss the elephants in the living room: liveability, comfort, productivity, health and well-being. After all, who wants to use a building that doesn’t satisfy these criteria?
Zack Gill is a research engineer at engineering consultancy Buro Happold