Locked in

We are all familiar with lockdown and the delay between taking action and seeing evidence of the effect of that action. Hywel Davies considers how that delay is multiplied by years when we look to reduce carbon emissions

We all know that in lockdown the delay between transmission of the virus and onset of symptoms means it takes weeks to reduce infection rates and case numbers.

There is an important and serious link between this and taking action to meet net-zero carbon emissions targets. The built environment has a long service life. What we build today will still be here in 30 years and, at current demolition rates, maybe 300 years. What we build today impacts our carbon emissions in 2050 and reaching our legal target of zero carbon emissions.

This affects not only the homes we build, but the 40 new hospitals, the schools, offices and retail premises, whether shops or warehouses. It may be argued that we focus too much on emissions from new buildings and not enough on the challenge of cutting emissions from the existing stock.

Without drastic cuts in emissions from current homes and buildings we will miss our 2050 targets. But this year’s new build is next year’s existing stock. And every year after. If not low carbon now, it must be retrofitted.


The decisions we take this year on ventilating our homes will have consequences for years to come.

As with virus transmission there is a delay between decisions about cutting emissions of what we build and achieving lower emissions – a delay of years! This is why it is so vital to adopt ambitious minimum standards for both new buildings and retrofit existing buildings too. Because what we do this year, next year and beyond sets emissions levels in 2050, and locks them in.

It’s also critical to get the associated review of Part F of the building regulations on ventilation right. The decisions we take this year on ventilating our homes will have consequences for years to come.

The pandemic has reminded us what Florence Nightingale knew well over 150 years ago: good ventilation helps reduce infection and promote recovery. And daylight helps, too.

While some are busy improving the ventilation of our homes and other buildings, there is a worrying upsurge of interest in devices to ‘supplement’ ventilation systems. Their effectiveness in reducing infection risk, their installation, the energy they use and emissions that they lock into our building stock are all unregulated. And if spaces were properly ventilated, they would be mostly superfluous.

It is not just about buildings. The current plan to kick-start the economy includes a major programme of road building for the lorries from new retail warehouses carrying our online shopping alongside our own cars.

Even if they are electric cars on ‘zero carbon electricity’, they need to be manufactured, they need batteries and the ‘zero carbon electricity’ needs to be generated. This is in addition to the electricity for all the net-zero buildings. And all that infrastructure has a carbon content to build, operate and maintain.

It is estimated that electricity demand for all electric buildings and vehicles will need two-and-a-half to three times current generating capacity. With the associated emissions locked in for decades to come.

We face really big decisions, now. Do we just power ahead with ‘decarbonised’ electricity, costing unknown tens of billions of pounds and relying on unproven solutions such as carbon capture and storage, or adopt hydrogen as an alternative fuel (leaving energy supply, cost and emissions to generate the hydrogen aside for now)? Or should we look at how to reduce energy demand radically, perhaps adopting some of the lifestyle changes of the past year?

The pandemic imposed immediate changes to how we live and work. While unwelcome in many ways, the pictures of our hospitals and rising human cost of SARS-CoV-2 left us no choice. The impacts and threats from our changing climate still seem less immediate, pressing or deadly.

We now have a chance to reflect on what we build, how we build it, how much energy it needs and how we live in it. And consider the long-term carbon consequences of our choices. The lag between decisions and consequences is long. Do we understand the gulf between the potential carbon consequences that these urgent decisions will very shortly lock in?