Figure 2 shows the problems inherent in making sense of self-assessed comfort data. Take a hypothetical work area. In this corner of a naturally-ventilated office, occupants have been characterised by their location to openable windows (dark blue seats), those who are part-time (pink seats) those assigned hot desks (yellow seats), those in deep-plan office space with their backs to nominated circulation routes (green seats), and colleagues who enjoy daylight via a rooflight (the yellow box). People represented by bright blue seats sit adjacent to a management office and meeting room and have little visual or acoustic privacy, nor do they have access to windows or environmental controls. They may be frequently disrupted by colleagues using the printer hub, and people wandering to and from the cellular spaces.
Let’s consider ventilation issues. Satisfaction with natural ventilation may depend on the ability to manage the trade-offs between ventilation and draughts, room temperature, radiant temperature, natural light and glare, and views out to the planted external landscape. Arguably such trade-offs can be managed best by those seated in the dark blue seats and closest to the control devices (windows and blinds). A democratic consensus over the position of these devices can usually be easily reached between two to four people – what one can call the control group – but gets progressively more difficult as the control group increases in size to include the orange seats. It may break down entirely with those in the red seats who may perceive conditions very differently to those in the blue seats, but are too far away to exercise control. A group of eight seats perpendicular to the window may be the limit at which democratic consensus can be achieved. Rows of desks longer than this may make consensus impossible. People may start to suffer. They may even become resentful of the building in other ways, which might breed intolerance of noise or other factors that other staff can tolerate.
Dissatisfaction with thermal conditions and indoor air quality may depend on exposure and dose rather than a particular instrumented level. Those only in the building for short periods (the part-timers) may be able to tolerate moderately adverse conditions. The hot-deskers may be also moderately more satisfied if they can choose their desk, or perhaps rotate position on a daily basis to share the benefits (and drawbacks) of a window location. Those sitting under the skylight may suffer downdraughts, but this will be offset by the (greater?) benefits of direct and indirect daylight, and possibly emotionally uplifting views of the sky.
Noise disturbance is often a major issue, particularly in open-plan offices. Those by an openable window are closest to external noise but have the ability to manage its volume. Road works can be suppressed by trading-off against ventilation, while birdsong may be welcomed. Again, those furthest away from the window will have less say over that control. Furthermore, those seated by the perimeter will be interrupted less by cross-talk and general movement in circulation zones, which will be suffered more by those in centrally-located desks. On top of that, noise conditions change during the working day. In open-plan, we all know hubbub can be useful in cancelling out irritating sources of noise. Those sources become a problem once the hubbub recedes.
Arguably, those seated in the green seats have the worst of all worlds. But, their jobs may mean they are less tied to their desks than other workers. They may be nearer the printers or the beverage points – both of which have advantages and drawbacks. Here, they have plants which soften the surroundings. Such characteristics won’t overcome shortcomings in the physical environment, but they might make those people more tolerant of noise, or lack of views out, or whatever.
The point of this example is that occupant wellbeing is highly variable and context-dependent. If one adds the effects of age and gender (particularly relevant for thermal criteria) the situation gets even more complicated. Then there is the availability of personal storage, or whether meeting rooms are readily available or always booked up, forcing irritated staff to improvise. Then add the issue of utilisation – how often all seats are occupied. At normal times occupant density may hover above the British Council for Offices recommendation of 1 person/8 m2, but at peak times it may fall below 1 person/6 m2, which might – might – start to hamper productivity and cause people to exhibit what one might call ‘escape behaviours’ to coffee points, atriums or even a home office. Will this typically human response be healthy one, or reduce productivity? How would you know? It all becomes statistically debateable.
Where does this leave the construction professional seeking greater certainty about the factors that determine wellbeing in any particular building? And, indeed, to know whether any of it really matters? Maybe we can always rely on the innate human ability to adapt to our environmental conditions, rising above all but the worst conditions to do a job of work well and happily.
In their influential 1997 paper Productivity: The Killer Variables1 (recently revised), Bordass and Leaman warned that the cats’ cradle of causality and association [of comfort factors] differs from one building to the next, making it dangerous to be overassertive about causation without careful appreciation of context. They identified five variables that have a critical bearing on the performance of occupied spaces, particularly offices:
- Personal control: People are generally happier with opportunities for more control and control over personal conditions and greater freedom of movement.
- Responsiveness: When people want conditions to change, they want that to happen quickly. That can be temperature levels, or a caretaker replacing a flickering fluorescent light.
- Building depth: Greater depth correlates with greater complication, use of air-conditioning with less personal control, and more dependence on facilities management, which has to be proportionately better.
- Workgroup size: Smaller and more integrated workgroups tend towards higher perceived productivity. Increased occupant density tends to break down perceptions of being in a smaller workgroup, with benefits of ease of communication with colleagues compromised by higher levels of unwanted noise2.
- Design intent: How well a building’s features work for its occupants. Features that are invisible, hidden from view, or not easily controllable will not be appreciated.
The inverse of the killer variables are buildings which are comfortable and controllable, with clear and well-communicated design intent, with usable systems that respond quickly to need. Shallow plan is generally better than deeper plan spaces, preferably with some form of natural ventilation. Careful management of zoning and control of density helps with control of many environmental variables, particularly ventilation, lighting and noise.
Will a greater focus on wellbeing in building design and management improve occupants’ actual experience? Maybe yes – it seems reasonable and much evidence suggests so, but don’t expect to be able to guarantee the optimisation of building design by applying generic, rule-based wellbeing metrics. For many contexts, elimination of fundamental causes of discomfort might be the best that can be achieved. Performance might be dictated more by the numbers of people subsequently piled into the building, and, for example, whether those people are happy queuing for unisex toilets at peak times. In an organisation with 60% women, it’s reasonable to say “probably not”, for many reasons too graphic to describe here. Use your imagination. But, does it matter? I mean, really? Definitive statistics or absolute values don’t exist. If the current focus on wellbeing leads to, for example, regulatory rules on occupant density and health and safety limits on persons per toilet, it’s a faintly scary prospect even if well-intentioned. Current data are not yet definitive enough.
My doctoral research, involving longitudinal studies of buildings over periods of up to 20 years, is generating some interesting statistics. In two notable office buildings (one a large multi-tenanted office), people reported spending up to more than an hour extra per day in the building, and more than two hours a day more on screen, than they had reported in the mid-1990s. That’s 10 hours more on screen, per week. This might include tablets and mobiles, but it is more likely to be sitting down in front of a screen (or screens) as these offices are still desk-based environments. How does this one factor inform ‘wellbeing’ assessments? Are people being more productive at the expense of their health? How does increased time on screen relate to their tolerance of the building’s environmental systems? Is it important, or is it not? Maybe they escape to Facebook or dating websites when they’re fed up with Excel. I’m not sure a “wellbeing consultant” would be able to put a weighting to that.
I asked a well-known social scientist what tools he thought most important when researching occupant satisfaction in buildings. Instrumentation? Physical measurements? Occupant surveys? “A functioning set of eyeballs,” he said. He had a point. Buildings aren’t nearly as mysterious as some people like to make out. Most problems are right in front of you, if you bother to look properly. The big question is whether what you’ve found actually matters. And that, as is often the case, is a matter of judgement.
Roderic Bunn is a building performance analyst at BSRIA and a postgraduate doctoral researcher at the Bartlett School of Architecture, University College London.