What is a ‘Healthy’ indoor environment? – Building Biology with Josh Wardle.

Before we get on to how to design healthy spaces, we first need to understand what a ‘healthy’ indoor environment is – and how to quantify and value it. I like to think of it as ‘where do most people feel the best?’.

For most, this is in the great outdoors; warm, dry, and with plenty of fresh air. This is reflected in the fact that the countries at the top of the world health index very closely match the countries with the most time spent outdoors in leisure activities.

In the modern world, we spend a lot of our time indoors. Our buildings are often overheated or overcooled, the humidity is unstable, and circulation of fresh air is limited. The goal of Building Biology is to understand the science and figures behind this, and ensure we design our places and spaces to achieve the best possible outcome.

One definition states health as ‘the state of being free from illness or injury’. Health & Safety and good design removes the issue of injury, which leaves illness. There are several things that can contribute to ‘sick building syndrome’ and various other illnesses, both physically and mentally, long term and short term. Examples include:

Temperature – meaning both surface temperature and ambient temperature, as well as heat distribution. Did you know the surrounding temperature of your environment can have a direct effect on your health? For example, rheumatoid arthritis can be aggravated in colder conditions. If your bedroom is designed with your bed up against a wall, and if that wall has poor thermal bridging (usually found at skirting level), then that localised cold spot could be directly impacting your health.

Humidity – if you step into your local swimming pool, you’ll notice that the humidity hits you straight away. If you pay close attention, it affects the depth of breathing, and it can also increase the rate a human body loses heat. In extreme cases, this can lead to dehydration, headaches, and even heatstroke in prolonged exposure.

Air Quality – insufficient air changes can cause a build-up of CO2 and VOCs which at just 1000ppm can start to cause symptoms of drowsiness or headaches. Too many air changes can cause a breeze, even in an insulated setting.

Building Biologists look to understand a room or building’s purpose, and then ensure the architecture and construction has been designed (or modified) to enable individuals to conduct these activities in the most healthy way.

The key is stability; by defining room environment parameters and specific material choices (plus treatments of those materials in specific areas early in a project) we can further enhance our spaces. By following the principles of Building Biology and through keeping the ‘Healthy’ indoor environment ethos in mind, we can start to better understand and design our projects around people, ensuring people remain at the heart of our projects.