The impact of buildings on our mental well-being and physical health is enormous
Buildings and the built-up environment undeniably have a strong influence on our health and well-being. The focus has shifted over the years from water and energy use to a more holistic approach that also takes into account how buildings affect the people who live in them. In buildings and the built-up environment, well-being and health are the new sustainability. And that creates opportunities.
Everyone healthy and WELL
One of the aims of green design is to make the built-up environment healthier for the resident. Healthier buildings are created by taking into account a wide range of aspects, which include indoor air and water quality, controlling noise and temperature, maximising preferably natural light or even encouraging more activity and movement. The WELL building standard provides designers with a guide covering no less than ten domains: air, water, food, light, movement, thermal comfort, sound, materials, mind and community.
Nature as an inventor
Nature provides inspiration. In addition, technology can provide a solution. Biophilia, or biophilic design, makes use of natural elements such as plants to improve the comfort experience or provide an inviting view that encourages residents to take the stairs. Biomimicry is the borrowing and adoption of solutions that nature has already invented for us. Examples include cooling systems that mimic the natural airflow found in termite mounds, efficient fans inspired by the shape of dolphin fins, or dirt-repellent paints and coatings modelled on lotus leaves. Applying circadian technology makes us go further than just saving energy. Circadian lighting supports following the circadian rhythm, the natural light-dark rhythm of a day.
Depending on the function of a building, energy costs are only a small percentage of typical operating costs. Concentrating on saving energy is therefore not always a good idea, especially when healthier, happier employees are the goal.
Ins and outs of healthy indoor air quality
With the COVID-19 pandemic, greater attention has recently been paid to airborne viruses as one of the parameters that can have a significant impact on the quality of the air we breathe and thus on our health. Air quality is of great importance and is determined by various parameters, such as chemical agents, particulate matter (or PM2.5), soot, volatile organic compounds (VOC) and nitrogen oxides. But microbiological agents, such as pollen and moulds, also help determine the quality of the air. For many, ‘air quality’ remains a problem of the external environment: a problem of mobility, industry and agriculture. This is true, at least in part.
Yet in our buildings, the air quality can be very different from that of the outdoor environment. Some pollutants may even be present in significantly higher concentrations. The air quality in a building is determined by 3 factors:
- The outdoor environment
- The building envelope
- The indoor sources
The outdoor environment partly determines the indoor air quality. These are chemical, biological and physical parameters (such as noise pollution). For example, heavy (freight) traffic in the vicinity will have an impact on the amount of soot or benzene in the immediate vicinity of a building.
This is why the building envelope also determines how much of that external environment penetrates a building, with the ventilation system being an important aspect. In the case of a controlled supply of outside air, the ventilation system offers the ability to purify the incoming air; for example, by means of filters, filter combinations or other air purification systems, specific chemical agents (such as fine dust, soot or volatile organic compounds), as well as pollen, can be removed from the air supplied.
The impact of indoor sources is often highly underestimated. These include building materials, as well as consumer products such as cleaning products, scented products, furniture, office equipment, electronics, but also activities that take place indoors, such as cooking, vacuuming or even just the presence of people. Low-emission building materials, furniture and decorative products are already an important step in the right direction: the emission of mainly volatile organic compounds from these products is considerably lower, thus greatly reducing their contribution to indoor air. A good product policy can ensure that only low-emission products can come onto the market (RD establishing threshold levels for emissions to the indoor environment from construction products for certain intended uses, 8 May 2014). However, for all other materials and products used in buildings, there is no legislative framework. Raising awareness among consumers, contractors and architects is therefore important. However, source and exposure limitation during each phase of the building process both remain the most important steps towards healthy indoor air in buildings. “Ventilation can ideally be limited to a minimum of 4 L/s per person, in a building with maximum consideration for source control,” concluded the European research project ‘HealthVent’. This source limitation relates to (building) materials and product use, but also to ‘people as an indoor source’, meaning that during a pandemic such as COVID-19, effective source limitation is (temporarily) impossible. The World Health Organization therefore also recommends better ventilation during the pandemic (WHO, ISBN 9789240021280, 1 March 2021). Controlled ventilation, which uses sensors to continuously monitor building usage and its impact on certain indoor environmental parameters in a building, is an important step towards making ventilation as energy-efficient and effective as possible.
Senior Researcher at VITO
Director of Cleantech Flanders