Biophilic Design – The New Way To Reduce Office Noise?

A simple introduction of natural lighting, outside views, and vegetation are ways to bring the outside world inside – to give building occupants a chance to engage with the natural environment and reap the mental and physical benefits that come with it.

One distinction to make about biophilic design, is the efficacy of consistent and immersive design, rather than single, isolated biophilic installations. Stephen Kellert, writing for Metropolis Mag puts it best: “simply inserting an object of nature into a human built environment, if unrelated or at variance with other more dominant characteristics of the setting, exert little positive impact on the health and performance of the people who occupy these spaces.”

Take Wood Bagot’s office in Melbourne, Australia, for example:

The studio’s design is a deliberate dedication to the incorporation of natural elements, which span the studio’s length. The sustained use of timber and greenery is an intentional effort to counteract the industrial finished of the studio, softening the aesthetic and creating a space that feels more like an airy balcony held aloft trees than merely an office decorated with plants.

The practice’s underlying theory contends that humans have a biological need to interact and observe the natural environment, and by satiating that need, Biophilic Design boosts individual happiness and well-being. It isn’t just theory, though; there are innumerable studies that support it:

Corroborating Biophilic Design

• One study from the University of Queensland School of Psychology examined the impact of ‘lean’ versus ‘green’ office space on employees from two large commercial offices in the UK and the Netherlands over a two month period. It concluded that an office enriched with plants makes staff happier and boosts productivity by 15%.
• Similarly, a 2015 report by Human Spaces found that workers with access to natural light and greenery reported a 13% higher level of well-being. Rather bleakly, the report also revealed that across Europe, The Middle East and Africa, 42% of workers had no access to natural light in their workspaces, 55% no greenery and 7% had no windows.
• In 2003 Genzyme Corporation designed a new corporate headquarters in Cambridge, Massachusetts, which achieved LEED’s Platinum Status. Features of the building include “natural light; a clear glass exterior; a central atrium with chandeliers at the base, which reflect sunlight; indoor gardens, and windows”. 18 months after the structure opened, a survey found that 88% said having direct views and access to the natural elements indoors improved their sense of well-being. Additionally, 75% said the building’s design increased their feeling of connection to their colleagues.
• A 2013 study out of the University of Essex found that visual exposure to the natural environment can reduce blood pressure and heart rate following exposure to a stressor. The study was carried out by comparing the physiological responses in humans to the built and natural environments following external stressors.
• If that doesn’t prick up the ears of business owners, then perhaps this will. A case study of an administrative office building at the University of Oregon found that workers with access to views of trees and landscapes took 10% fewer sick days than workers with ‘unnatural’ views. The study compared 30% of offices that overlooked trees and a manicured landscapes with 31% that overlooked a street, building and parking lot and 39% offering no outside view at all. Workers with natural views took 57 hours of sick leave per year, compared with 68 hours for those with no view. The study also monitored the workers’ break patterns and found that those with landscape views sat at their desks for longer while those with no view took exterior walks and longer breaks.
• A detailed list of the health benefits of biophilic design include can be seen in the table below from Terrapin Bright Green from their 2014 report ’14 Patterns of Biophilic Design’.

One of the often overlooked benefits, however, is acoustics.

While biophilic design can undoubtedly make a happier office worker, what is making office workers unhappy in the first place?

A 2013 study out of The University Of Sydney found that the greatest cause of dissatisfaction amongst workers across all office types was the lack of sound privacy, overwhelmingly so:

This was followed by temperature, visual privacy and noise level.

The good news is that Biophilic Design can improve all these factors.

The benefits of green walls and roofs on a building’s energy performance are well documented. One study from the Australian Government revealed that green roofs can be up to 20.5°C lower in summer months when compared to uninsulated steel roofs.

Plants, of course, can also provide visual privacy.

Of even greater importance, however, is the ability of plants to reduce noise levels.

One such study has come out of The University of The Basque Country. The study tested the acoustic properties of modular green walls using two different reverberation chambers. It showed that green walls, when compared to untreated walls, resulted in “a weighted sound reduction index (Rw) of 15db and a weighted sound absorption coefficient (a) of 0.40”.

The spearhead of the study, Zaola Azkorra stated that the study demonstrated that “the green wall showed a similar or better acoustic absorption coefficient than other common building materials, and its effects on low frequencies were of particular interest”. Azkorra has suggested that this points to new uses for green walls in public places such as restaurants, workplaces and hotels.

But just how to plants manage noise? There are a few ways:

Sound Diffusion

One of the main ways plants and shrubbery can manage noise is by diffusing sound.

When soundwaves strike a flat surface such as masonry, marble or plasterboard, they are reflected uniformly and in a straight line, thanks to the smooth flat surfaces. Diffusion occurs when sound waves strike a dynamic or uneven surface, breaking up the uniformity and concentration of the sound waves and scattering them evenly around a room’s area.

Plants and shrubbery are naturally uneven, and when sound waves hit their surface, they are reflected around any given space more evenly, reducing echoes and the intensity of sound.

Sound Deflection

Plants can convert sound waves to other forms of energy – in much the same way that acoustic panels absorb sound by converting sound energy into heatwaves.

When sound waves hit a rigid surface such as marble, they are immediately deflected back into the room. When sound waves strike a flexible material, like plants, the material will vibrate and the waves are transformed into other forms of energy.

Here are some pointers to using plants effectively in your office:

• Spread plants evenly throughout the space, as clustering them in one area will not produce the desired effect.
• Use green, modular walls that have been tried and tested for their acoustic properties in order to effectively manage and control noise. Companies such as Acoustic Factory and Ambius have products that meet international acoustic standards.
• Kenneth Freeman, the head of innovation at Ambius suggest using large plant containers with more compost and with a greater area of top dressing. As Freeman states: “both of these have a significant effect on noise reduction, so it follows that they make a larger impact on the room acoustics. Experiments have shown that arrangements of different plants in groups appear to work better than individual plants.”
• Use plants and shrubbery as natural dividers in open-plan offices. Instead of unsightly partitions, consider placing dense foliage ontop of filing cabinets, or on desks, to create a natural and sound absorbing barrier between workers.