By: Hywel Lloyd, Government Engagement Manager, and Jo Atkinson, Building Project Engineer, Active Building Centre Ltd
As the UK looks towards recovery from the impact of the COVID-19 crisis, many people, businesses and organisations are calling for a green recovery. That makes sense, given the future must be greener.
As ever, the question is going to be, what’s best to focus on? The UK has long had policies to address the poor energy efficiency of homes. It has been a long-term challenge, given that many of them were built before the concept of building regulations.
And, as with all regulations, the mechanism lags behind both the technology and the innovations that are available to make for better homes.
The big upgrading challenge
Given the scale of the challenge, and the recession we face, it would make sense to pick an opportunity that itself is a significant challenge.
The economic win of upgrading our homes from whatever state they are in to the standards required for the 21st century is massive. Of our approximately 27 million homes, we have perhaps as many as 25 million that have been built to standards that we would now say are insufficient.
This is a challenge that offers a significant opportunity for almost every community, which in turn resonates with the general political ambition for ‘levelling up’ UK regions.
Retrofitting our housing stock
While there have been policies, programs and resources for retrofitting housing stock, many would recognise they have been insufficient in scale and nature.
There is also an issue about the whole idea of retrofit, given it is saying to many people “your house is in some way deficient and we will come in to make up for that deficiency”!
And then often all that happens is a boiler replacement with some new insulation, be that in spaces that hadn’t originally been designed for it (older homes), or where it may have been forgotten (newer homes with poor quality assurance).
Choosing the right upgrade
The more we think about what is required, the clear sense is that we need to move towards the language of improvement, or ‘upgrade’, a phrase that people understand in their everyday use of things like their mobile phone.
So, let’s upgrade our housing stock. It’s the most potent route to a green, levelling-up recovery that we have.
In the first instance we need to think about the state of the housing we currently have. Some of it is quite old, some of it was built to ‘breathe’ with fireplaces and wall materials that are not meant to be impervious.
Then there are post-war homes which offer clear opportunities to improve the building fabric (wall materials, cladding, insulation) at relatively low cost. Even homes built more recently may have limited scope for fabric upgrades, given how they have been built.
Technologies of energy
A nuanced approach to upgrade would recognise that there are some homes where you would start with fabric improvements and reduce net demand, and there are some other homes where you might start with the technology of energy.
Building-based technologies of energy include all those things that allow you to capture or generate energy on or off the building. It includes all of those technologies that allow you to sense the state of the house and its energy needs, then manage and control how energy is used in and around the building.
It also includes those technologies that flow energy to meet any need that we might have, such as charging an electric car, a computer for leisure or work, or to heat space, water or food.
Improving technology or fabric
First making improvements to building fabric is both theoretically the best approach and often the best practical route, given that it reduces the energy we need to achieve the desired performance.
Yet there will be a significant number of homes where fabric upgrades are disproportionately invasive or expensive. A more effective response should then be to start with technologies of energy.
For a number of homes and home types it will be more effective and more deliverable to upgrade with technologies of energy, rather than to start with (or only focus on) the state and efficiency of their building fabric.
If you accept this approach, we can look at different typologies of home and start to understand the best 21st century energy technologies for each type.
Different approach for different houses
We recognise that in some cases this approach will mean no attention to fabric efficiency because of the nature of a particular home type. Equally, for some cases the home energy technologies may be somewhat over capacity as a result.
We do not consider this as a disadvantage as long as we ensure all of these future technologies are renewable, have a low whole-life-cycle carbon impact, and increase the level of local energy generation or capture.
There are plenty of benefits these technologies offer the energy system, including reduced peak and lower fossil fuel demand.
Exploring the potential for upgrades
It may also be the case that it is easier to engage homeowners in upgrading their home with new energy technologies than in carrying out a retrofit, especially where that involves working on the fabric of the home.
We have proposed that the Department for Business, Energy and Industrial Strategy’s Select Committee starts an inquiry into the potential of an upgrade approach as part of their parliamentary work. We will take a similar approach with the current Energy Attribute Certificate inquiry into home energy efficiency.
We look forward to working with anybody who sees the potential of the upgrade approach, and has the tools, techniques and technology, in addition to those being developed at the Active Building Centre, that may help to deliver it.
Active Building Centre
The Active Building Centre (ABC) is a £36 million investment made by UKRI under the ISCF transforming construction challenge.
The ABC programme aims to transform the UK construction and energy sectors by demonstrating and advancing best practice net zero carbon technology for so-called ‘active buildings’, that generate and store their own electricity.
Last updated: 28 January 2021