Healthy Buildings Heroes Part 1.


Ruth Kelly Waskett, Senior Associate

Ruth Kelly Waskett on the power of daylighting.

It’s not every day that you hear lighting likened to sweet treats, but expert Ruth Kelly Waskett has an astute analogy.

When it comes to lighting, I often draw parallels with nutrition. You can get your calories from chocolate, or you can get them from vegetables, but it’s not quite the same.

Those calories are packaged differently and received differently by your body, and with lighting it’s similar.

Ruth is talking here about the difference between artificial lighting and daylight. While both are essential to our lives, there are fundamental variations between the two. The full light spectrum can only be found in daylight and, even on a cloudy day, it still provides more powerful rays than anything you’ll find indoors. Add to that its mood-boosting, vitamin D enhancing qualities, and it is a formidable life force.

Daylight and artificial light have very different characteristics, and we know that we need natural light in order to thrive. I’m very interested in how we integrate the two – it’s easier said than done. I’m particularly passionate about daylight, because it’s so crucial to architecture and to our lives. We need it in the same way that we need food and water, and as lighting designers one of our major focuses is on harnessing it and using it as part of a holistic lighting design practice.

Lighting for people

It is a powerful CV, and Ruth is passionate about extolling the many virtues of daylight, especially within the workplace. After all, we know beyond doubt that light and wellbeing are inextricably linked. Light kickstarts our body clock and influences our mood, energy levels, sleep and visual comfort. But while the light-dark cycle has shaped the rhythms of human existence for centuries, many discoveries around light and our wellbeing are relatively recent.

Around the year 2000, it was discovered that we have light receptors in the back of our eye that exist purely to regulate our body clock. We always think of the eyes as being there so we can see, but perhaps their first purpose was to enable us to synchronise with the light / dark cycle of the earth.

We know we need a good blast of light in the morning period, in order to reset our body clock every day – it’s like resetting a watch that goes slightly out of time. So, when it comes to designing buildings, it’s particularly important for people to have light exposure in the mornings.

Architectural advantages

Ruth adds that there are psychological and even architectural benefits to incorporating light into a workplace too.

It means prioritising windows, which then give you a connection to the great outdoors. Even in an urban environment, you’ll see a few pigeons and be aware of the weather patterns. Just being able to see the sky and get those visual cues about the time of day and the seasons is very important to our wellbeing. Having the opportunity to look into the distance through a window is good for our eyes too. It relaxes the muscles that are involved in working with a screen and, without those opportunities, we can suffer eyestrain.

Indeed, numerous studies point to the dividends of daylight. Research by Cornell University Professor Alan Hedge found that workers in office environments with optimised natural light reported an 84 percent drop in symptoms of eyestrain, headaches and blurred vision symptoms. Likewise, workers sitting close to a window that optimised daylight exposure reported a 2 percent increase in productivity.

On the flip side, studies suggest a persistent lack of daylight – or repeated exposure to light at the wrong time – has the potential to be harmful. Light keeps the clocks in our cells synchronised, something which is critical for optimal health. Disruption to the body clock can lead to symptoms of SAD (Seasonal Affective Disorder), sleep issues and potentially may even increase the odds of certain cancers.

A lack of legislation

Despite all this, Britain has been slow to introduce legislation to ensure workers have sufficient access to natural light. While countries including Germany and Sweden have legal minimum standards, the UK’s guidance is vague at best.

There are guidelines and standards around daylight, but none of them are legally binding.

Lighting is all-too-often seen as just another building service, but it holds the key to providing enjoyable and health-supporting spaces for people.

Of course, in recent years LED systems have revolutionised the lighting industry. While ‘old fashioned’ tungsten or incandescent bulbs didn’t emit blue light, LED systems can be engineered to more closely replicate natural light. This means we can develop light sources designed to deliver the circadian-boosting light when we need it and when the sun goes down, this artificial lighting can be extremely supportive. It can deliver warmer temperatures, to help our bodies wind down towards bedtime, and has a huge ability to create a visually stimulating or intimate atmosphere through colours and pools of light.