Research | Biophilic office In addition, internal light levels are continually monitored using ceiling-mounted light sensors in representative office locations, and external light levels using roofmounted daylight sensors. The BRE lighting team is currently conducting computer modelling of the existing electric lighting and daylight distribution in the offices, using the monitoring data to calibrate the model. By modelling annual profiles of daylight illuminance at eye level, and of total eye-level illuminance, they are estimating the levels of circadian stimulation for each person working in the offices. All findings will be included in a pre-refurbishment lighting report. In conjunction with the BRE social research team, the BRE lighting team is setting up a protocol to monitor occupants continuous exposure to light, which will be implemented in the post-refurbishment phase. Artificial skylight mimics sunlight and the Rayleigh scattering process that creates the blue colour of the sky Lighting Cosmin Ticleanu, BREs electric lighting expert on the project, says that although lighting plans are still to be finalised, in the office areas they are likely to make use of floor-standing luminaires, placed close to each desk to give upward and downward light distribution. The upward lighting will make the ceiling more brightly and uniformly lit, reducing the existing contrasts in the visual field that can cause discomfort especially for those spending long periods of time in the office, he says. We are considering using automatic controls for the upward lighting and, potentially, providing light levels that follow the natural pattern of light throughout the day starting low and rising to a high point around noon before reducing again as the day progresses to evening. But control of the downward component, which will light the desk and task areas, is likely be given to the building occupants so that peoples varying lighting preferences can be fully accommodated. While the predominant lighting will be from floor-standing luminaires, there will also be suspended and recessed fittings. Colour temperature, both static and changing, will form an important part of the study. Half the project is biodynamic, the other half is split into 4,000K and 3,000K zones, says Jim Ashley-Down, managing director at Waldmann Lighting. All of it is designed to comply with [workplace lighting guide] LG7 even though there are various biophilic and biodynamic elements to the overall design that make this difficult to achieve. He says there is the conflict between the Monitoring of the offices and occupants will be widely publicised to help ensure health and wellbeing become routine elements of office refurbishment light levels required by LG7 for a workspace for example, 500 lux on a desk and the requirement for biodynamic lighting to be at a lower intensity at the end of the day. Also, an important design element of a biophilic space is the colour, texture, and visual interest of the walls. In LG7, reflectance values and neutral surface colours must be allowed for to fully comply but, when walls have colours and/or patterns or are obscured by plants or green walls, it can directly impact the lighting in a way that contradicts LG7. He says: To overcome this, there needs to be far greater communication within the design team than usual to make sure the lighting, surfaces, and objects placed within the space work in a holistic way, rather than the usual engineering approach of the lighting calculations largely being done in isolation of the interior design. Another partner will supply ceiling light fittings to act as artificial rooflights, creating the appearance of sky and sunlight. The light fittings project light through a mini atmosphere of nanoparticles to create a scattering of light, says Ticleanu. This mimics the scattering of the suns light by the Earths atmosphere, giving an attractively realistic rooflight effect. The evidence from pre- and postmonitoring of the offices and occupants will be widely publicised to help ensure health and wellbeing become routine elements of office refurbishment through biophilic design. The aim is that future workplaces will enhance the mental, social and physical health and wellbeing of their occupants and, in turn, enable better business outcomes for office-based companies. CJ For details, visit www.bregroup.com/biophilic F lavie Lowres is associate director at the BRE Research and Strategic Advisory Group 16 December 2018 www.cibsejournal.com CIBSE Dec18 pp14-16 Supp Biophilic.indd 16 23/11/2018 12:57