Throughout the lockdown period of Covid-19, the positive benefits of cleaner air as a result of reduced transportation and halted industry have been felt by many. As we begin to return to typical habits of the past, it is vital to ensure that best-practice is adopted when considering the impact of emissions from everyday activities, and the air pollution caused.
Why is it harmful?
Air quality is the largest environmental health risk in the UK. It is widely known that ambient air pollution is a major factor causing detriment to health globally, with respiratory and pulmonary diseases having the greatest effect on populations. The World Health Organization (WHO) state that air pollution accounts for 29% of all deaths from lung cancer and 43% of those from pulmonary diseases1, with less threatening effects causing both short and long-term health implications.
Poor air quality is not only affecting human health; ecology, the economy and buildings themselves are also negatively impacted.
The built environment contribution
A building is a significant contributor to emissions over its lifetime. From the creation of building materials, construction, transport, the combustion of fuels for operation and demolition; buildings have a large impact on the quality of air around us. The built environment sector is responsible for 39% of global carbon emissions, with 28% of this attributable to operational energy use2.Operational energy use is largely driven by heating and lighting, with the demand for cooling expected to increase as a result of global warming. It is important to understand the existing impacts from this sector in order to address how to improve and minimise these negative impacts. Whilst inadequate ventilation may be a common cause for higher levels of indoor air pollution, reducing the concentration of these pollutants at the source is essential. Some examples of internal and external pollutants released as part of the construction and operation of buildings are given below:
- Particulate matter (PM2.5/PM10) – released from vehicles used in construction processes.
- Hydrofluorocarbons (HFCs) – cooling agents used in air-conditioning systems and refrigeration units.
- Carbon dioxide – released following combustion of natural gas for heating.
- Volatile organic compounds (VOCs) – emitted from building materials.
What is being done to improve the situation?
The net zero carbon legislation passed by the UK Government in 2019 will drive reductions in greenhouse gas emissions, tackling climate change and improving air quality. Published the same year, the Clean Air Strategy 2019 sets out the actions required to meet pollutant reduction targets, with significant investment to be made in analysing air quality and its impact. Improving the energy efficiency of the domestic housing stock as well as all other use buildings, coupled with developments in renewable energy and their further roll-out, would drastically reduce levels of air pollution.
Air quality is a recognised issue in BREEAM assessments, the world’s leading sustainability assessment method for non-domestic buildings. Air quality is explicitly included in several of the issues covered in an assessment, such as Health and Wellbeing and Pollution, however it is embedded in the nature of many others. As can be expected, heating supplied by non-combustion systems is encouraged, and those with combustion plants cannot exceed certain levels in order to achieve credits. An increasing trend in the uptake of BREEAM assessments3 will hopefully aid in tackling air pollution.
In terms of the embodied emission impact in construction, locally and responsibly sourcing materials and optimising the use of recycled or repurposed materials would lower the pollution levels associated with production, transportation and construction. Research is currently being conducted to investigate methods of brick production with reduced emission levels, with alternatives to traditional kiln firing reducing emissions by over 90%4. In addition, modular construction practices are being utilised to reduce construction dust, inhibiting the release of pollutants due to wind dispersion.
The Committee on Climate Change state that the UK’s climate objectives cannot be met without major improvement to the housing stock. This includes essential upgrades such as installing energy efficient measures and low-carbon technologies. Whilst emissions per household are much smaller than for larger non-domestic buildings, the 29 million UK homes have a powerful collective input, forming 14% of total UK greenhouse gas emissions5. The Zero Carbon Heating Taskforce was recently launched to examine the barriers to investment in domestic retrofit, aiming to enable every household to access zero carbon heating.
Measures to improve the quality of air are reflected in the holistic UN Sustainable Development Goals, namely Goal 3 – Good Health and Wellbeing, and Goal 13 – Climate Action. As said by Dr Tedros from the WHO on 7th September, “Let’s make the choice for clean air and blue skies, it is within our reach”.
There are currently many organisations and campaigns with a unified goal of combatting air pollution, such as the Climate and Clean Air Coalition and BreatheLife. Much like the ‘International Day of Clean Air for blue skies’, these aim to raise awareness of the risks of air pollution and promote positive change.
What can you do?
Through sustainable design, effective construction and building operation management and increased understanding of how to tackle the threats posed by air pollution, we can reduce the number of deaths and provide cleaner air for the future.
I encourage all readers to learn more about how the built environment is impacting air quality and raise awareness of the importance of clean air with family, friends and colleagues. Solving this issue requires a global collaborative effort from all sectors, not just the built environment.
1World Health Organization., 2020. Ambient air pollution: Health impacts. Available at https://www.who.int/airpollution/ambient/health-impacts/en/
2UN Environment and International Energy Agency., (2017). Towards a zero-emission, efficient, and resilient buildings and construction sector. Global Status Report 2017.
3Prior, J., Holden, M. and Ward, C., (2019). The Digest of BREEAM New Construction and Refurbishment Statistics 2013 to 2017.
4IIASA., (2017). The GAINS Model – A scientific tool to combat air pollution and climate change simultaneously. Available at https://iiasa.ac.at/web/home/research/researchPrograms/air/GAINS.html
5Committee on Climate Change., (2019). UK Housing: Fit for the future?