The secret acoustic benefits of plants at the office

Acoustic insulation in the form of lush green walls is a sound approach every landlord should consider. 

Phone chatter, obnoxiously loud conversations in adjacent cubicles (we've all been there,) printers, photocopiers, HVAC systems... all distract and make employees less efficient. There are several ways to remedy noise levels in the workplace - sound absorption and sound masking are increasingly popular strategies, but what about living plants?

In 2015,  an agricultural engineer of the University of the Basque Country conducted a research on the benefits of green walls as passive acoustic insulation for buildings. Zaloa Azkorra concluded 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.”

Despite a rising number of studies highlighting the acoustic potential of plants, biophilic design is a resource yet to be explored by acousticians, particularly in sectors like the workplace, still in dire need of fine tuning.

NB: Biophilia refers to the innate love for the natural world, in other words, for nature and the outdoors.

Segment's office reception

How do plants regulate noise in the workplace?

To understand this, we must first brave the acoustic jargon and grasp the meaning of reverberation time.

Let's get technical for just a sentence. Reverberation time refers to the time it takes for a sound wave to die away to a level 60 decibels below its original level. And now, in English: when a source creates a sound wave in a room, what you hear is not only the sound wave spreading directly from the source, but also the sound reflecting from various surfaces around you.

Let's put this in context. The average reverberation time (now that you're an expert, we can call it RT) in an open plan office should be less than 1 second. In an enclosed office, the recommended  RT is less than 0.6 seconds. In a meeting room, 0.6-0.8 seconds. What does this mean? Simply that an open plan office sporting an RT of 0.6 seconds will be significantly quieter than one with an RT of 0.9 seconds.

But how exactly can plants help reduce reverberation time, and therefore noise levels, in your office?

Partitions with integrated living walls. Climate Office Mobile Wasserwand. Manufacturer: C+P Möbelsysteme

Sound deflection

When sound hits a masonry wall, it bounces off the rigid surface and back to its source, like a solitary tennis ball between a racket and the wall. In contrast, when a sound wave hits a plant, the flexible surface will vibrate and transform sound waves into other kinds of energy. This is the same principle behind acoustic panels that absorb sound by converting sound energy into heatwaves.

Partitions with integrated living walls. Climate Office Mobile Wasserwand. Manufacturer: C+P Möbelsysteme

Sound diffusion

There is a clear correlation between the way sound behaves and the surfaces around it. Think of a home with a carpet versus a home with solid floors. Usually, a carpeted room will prevent the sound from bouncing all over and creating echoes. Much like a carpet, plants and shrubbery are naturally uneven - covering surface areas with greenery will help accomplish the same feat. Think vines on walls, lawns, green walls, moss walls, etc.

Moss Wall by Dutch designers Oasegroen

How to use plants to reduce noise?

Genzyme Center, Massachussets, USA. Architect: Behnisch Architekten, Los Angeles

Rough bark and leafy plants are particularly effective but for maximum acoustic potential, you should also consider number of plants, location, size and surface area.

Large planters

Larger planters contain more compost and provide more space for greenery. Combined, these two have a significant impact on noise reduction. As a result, your office benefits from better acoustics, and cleaner air. It's a win-win.

Tip:  For better acoustics, arrange your planters throughout the space as opposed to clustering them. It's all about that surface area - the more spread out your plants are, the more opportunites there are for sound diffusion.

Focus on corners, edges and walls

Along the same principle, plants placed in the periphery of your office - corners, edges, walls - are more likely to reflect sound than plants placed in the middle.

Woods Bagot Melbourne studio

Replace partitions with plant screens

Offices are inherently loud - open plan offices even more so. Oftentimes, this means partitions or rows of filing cabinets. What if you could use plants instead? Effective in reducing noise, and more attractive than your average office partition, plant screens are a great alternative.

If your tenants are reluctant to lose the filing cabinets, these and other surfaces can also be used to place small bushy plants in narrow containers.

Joost Bakker’s Schiavello Vertical Gardens

Biophilic design guidelines for good acoustics

If utilised strategically, biophilic design can drastically improve acoustics in the office and its common areas.

There are few studies on the relationship between plants, architecture and acoustics. In a study performed by P. Costa of the South Bank University in London (1995,) Costa tested several single potted plants and combinations of plants in various areas in a room. His conclusions amount to a certain number of guidelines covered above.

If you accidentally skipped to this last paragraph, here's a summary:

  • Plants need to be large and healthy
  • Plants should preferably be leafy
  • Arrangements with a minimum of three plants seem more efficient than single plants
  • Spread out arrangements are better than a concentrated few plants.
  • Placing plants alongside walls has a greater impact on acoustics than if they're placed in the middle of a room
Opening image: Slack office, Melbourne. Breathe Architecture

What will the office of the future look like?

Ljubljana chamber of commerce boasts biophilic design

From energy-saving to family-conscious, the office of the future will be greener, smarter, and undoubtedly more high-tech.

Office design is changing fast. Designed to adapt to the workers' needs, the office today wants to be open yet flexible. But what about tomorrow? What trends are bound to shape the office of the future? 

Hot-desking

Hot desking inside Air bnb's Tokyo office
Hot-desking area inside Airbnb's Tokyo Office. Suppose Design Office

A recent CBRE report has found that, of the 400 multinationals surveyed, two-thirds plan on embracing the shared-desk concept by 2020.  As versatility becomes the new status quo in the workplace, traditional open-plan offices are already giving way to activity-based working solutions where flexibility is key and the price of a desk has to be justified. 

Energy-saving buildings

bloomberg hq in London is billed the most sustainable office in the world
European Headquarters for Bloomberg, London. Foster + Partners'

With concerns over climate change growing stronger every day, sustainable design is becoming a key practice for developers, architects and engineers alike. 

Anecdotally, Foster + Partners' recently completed European Headquarters for Bloomberg in London was recently voted as the most sustainable building in the world, and it serves as a great example for the future of commercial properties and green building. 

With a BREEAM score of 98.5, the office building features bronze louvres that adapt to changing weather conditions, sensors that adjust airflow according to occupancy, rainwater and water from basins and showers harvesting technologies, and of course, an indoor green wall. Combined with that, Bloomberg's employees will profit from sit-stand workstations, two on-site cycle centres as well as a wellness centre, accentuating the importance of wellbeing in the workplace

Wearables for office workers

don't slouch wearable for work
Anti-slouch wearable by Upright

From activity-trackers, through real-time translation devices, to posture-correcting wearables, high technology is creeping up in the workplace, whether you like it or not. As staff wellbeing becomes increasingly important for productivity and business, will the employer be responsible for providing health-tracking wearables at the office? 

Some American companies like IBM, Time Warner and Target have already partnered with activity-trackers like Fitbit and implemented their own corporate wellness initiatives.

Health insurance giant Vitality has set in place incentives for their employees: hit your step goal and get a discounted Apple Watch!

On-site nurseries

Office nursery visualisation for Second Home in London
On-site nursery proposal, inside London's Second Home Spitalfields. José Selgas and Lucía Cano

In 2003, Goldman Sachs London office opened the first (and to this date only) on-site nursery in the Square Mile.

According to the latest figures from the Chartered Institute of Personnel and Development, Goldman Sachs is one of only 5% of businesses in the UK to offer childcare in the workplace.

Unsurprisingly, that 5 % is exclusively made up of large organisations with funds that match the financial requirements for an on-site creche in the workplace, but the benefits for companies are not insignificant. 

For starters, companies get tax breaks and relief for the day-to-day running and capital costs such as lighting, heating and the premise. On-site nurseries also have an impact on staff retention, making for an easier transition from maternity leave to work.

on-site nursery inside Goldman Sachs London
On-site nursery inside Goldman Sachs London office on Fleet Street

Despite their evident appeal, on-site nurseries at the office still pose significant challenges, as pointed out by Rohan Silva, former government adviser who now runs creative workspace Second Home in East London. These include a costly Ofsted accreditation process and frequent inspections, a chronic shortage of trained staff, strict regulations around designing and building childcare facilities and the need to shift the property developer's mindset. 

All things considered, on-site nurseries in the workplace are a profitable market for landlords and property agents to tap into. 

Biophilic design

Ljubljana chamber of commerce boasts biophilic design
The Ljubljana Chamber of Commerce and Industry in Slovenia. Sadar+Vuga Architects

In line with a more sustainable environment, the office of the future is set to embrace biophilic design. From planting living walls to maximising natural light and improving air quality, offices will pay more importance to staff wellbeing, health and productivity. 

3D printing

3D-printed office in Dubai
The world's first 3D-printed office in Dubai

The use of 3D printing in architecture has yet to reach its full potential and yet, Dubai has already unveiled a proof of concept set to redefine our expectations. 

The world's first 3D-printed office was built in 17 days and cost £110,000. It took a team effort of eighteen people only to oversee the process from start to finish. 

Technology research company Gartner expects 75% of companies to use 3D printing to increase manufacturing by 2020

Remote working

husk coffee and creative space in East London
Husk Coffee And Creative Space, East London

Having said all that, the office of the future might not be an office after all. Ever since the internet infiltrated the workplace in the late 1990s, remote working has been gaining momentum. Industry experts have even started to question the need for an office space

Coffee shops and hotel lobbies already double as informal office spaces, highlighting the possibility of an altogether barrier-free office.

So, how important is the need for an office space? Have we missed a crucial trend? Tweet us your thoughts - we love to be challenged. 

Opening image: Ljubljana Chamber of Commerce and Industry, Slovenia. Sadar+Vuga Architects