Climate change and the air inside public buildings

Chris Yates, chief executive at Federation of Environmental Trade Associations, explores the issue of indoor air quality and the need for better ventilation in public buildings, as well as the effect that heating requirements can have on the environment

Arguably the UK did a good job at COP 26. For the first time ever, reduction in fossil fuels was included in the text, which I think for many of us was a surprise as it had not been included before. However, that is often one of the challenges of bringing countries together, coming from different perspectives, and it sometimes takes a long time to get people on to the same page.

Although I am sure we have all wanted to see more progress being made in terms of how we deal with climate change, I for one am very encouraged by the fact that these discussions are going to take place again next year and will look at how the targets can be reduced and improved further. It is essential to get these targets properly defined and measurable, so we hit them, but not miss the point on climate change.

In parallel with a drive towards the net zero target we know that as the planet starts to heat up, this is going to increase the chances of poor indoor air quality (IAQ) which we will need to address through ventilation, cooling and air conditioning. Indoor air quality will need to be addressed through summits such as COP 26 and through our own regulations covering buildings to ensure that we have safe environments for people to visit and work, particularly in public buildings. Different challenges are going to be present depending on the use of the building. The impact of the pandemic has meant many of the buildings have not been utilised fully and will need to be assessed to ensure ventilation systems are working correctly.

Employee welfare
We also have to assess the impact of hybrid working which is likely to be a permanent feature of the workplace going forward. That could mean that office spaces have a lower utilisation rate, effectively moving the IAQ problem to another building i.e., the employee’s home. We need to recognise this in our assumptions about the workplace going forward that it is equally important to ensure good IAQ at both the office and the home if we are to properly consider the welfare of our employees. CO₂ emissions not only harm our planet, but us too as it impacts on our productivity. The landscape has shifted to one where we have a wider building footprint that is not the obvious bricks and mortar that we had before the pandemic and due consideration needs to be given.

For buildings that we see returning to, hopefully, normal occupancy as we come out of the pandemic, risk assessing existing buildings by a commissioning engineer is crucial to ensure that the existing ventilation operates correctly, but also that it is capable of managing the risks of Covid in buildings where there is likely to be a very high footfall. This should already be part of the procedures that the building operates to, but it is well worth reviewing given the impact of Covid and likely changes in working practices that could impact the building as well.

There is also an opportunity to educate when considering how to improve the IAQ of buildings. Visitors and employees are likely to see public buildings as an exemplar when it comes to how the building is managed. Reassurance that the air quality is being monitored and managed by the facilities management team gives an opportunity to engage with users in a positive manner to show what we are doing to protect them. Given the high profile of the term ‘net zero’ this can be used to hang many messages off the back of as consumers are seeing the term on a regular basis through the media, particularly as a result of COP 26. Looking at research over the last 18 months, produced by BEIS, awareness has been on the rise.

Linking net zero, IAQ and climate change together gives an opportunity for the education of employees, visitors, and users in terms of how all three pillars fit together and also the plan to go forward. Many companies have a sustainability statement so why not have a plan for buildings that is publicly available, particularly when the costs can be shown against the savings both in monetary and well-being measures that can justify the investment.

Overheating
As part of the impact of climate change, what many public buildings are going to have to deal with going forward is the issue of overheating. This is currently being considered as part of the building regulations review for England.

The Zero Carbon Hub’s working definition of Overheating is: “The phenomenon of a person experiencing excessive or prolonged high temperatures within their home/building, resulting from internal and/or external heat gains, which leads to adverse effects on their comfort, health or productivity.”

There are a number of factors that can affect overheating:
•    Location: The climate tends to be hottest in South East England, dense urban neighbourhoods are at higher risk.
•    Fabric characteristics: Highly insulated buildings, darkly coloured external walls, sky lights or large areas of unshaded south, east, or west facing glazing.
•    Occupancy/behaviour: In the building all day can be at high risk, temperatures higher in the early afternoon.
•    Sun can be a risk.
•    Type of property: Top floor of buildings can absorb a lot of heat through the roof and can be more exposed to direct solar radiation.

To mitigate this, ventilation is the main method of removing heat from dwellings in the UK. Providing the outside air is cooler than inside, ventilating a dwelling with fresh air will help to lower the internal temperature. Air movement over the skin also has a perceived cooling effect.

Overheating issues may increase as existing buildings are better insulated to enable them to achieve net zero.

Fabric First
I would strongly advocate ‘Fabric First’ for any work being done on a building to reduce the input of energy required. With good planning of the design of the building and services, the effects of overheating can be minimised, but ventilation alone will not eliminate overheating.

Being able to measure the CO₂ levels in a building is very important as we know this impacts on the cognitive performance of individuals. This is true for schools, offices and public access buildings and assessments need to be made to determine the optimal CO₂ management strategy as well as how to deal with other pollutants that should be covered under the risk assessment.

And finally, government has put together a new campaign demonstrating the importance of simple ventilation techniques to reduce the risks of catching Covid-19 this winter. The campaign comes as new research reveals two-thirds (64 per cent) of the public did not know that ventilation was an effective way to reduce the spread of Covid-19 at home. Only around a third of people (29 per cent) are currently ventilating their home when they have visitors. Only three per cent of those surveyed continued to ventilate their homes for a period after their guests left. We can apply this thinking equally to buildings to mitigate the risks.