In September 2021, drivers on the M25 motorway were surprised on their morning commute by a group of activists blocking the road and demanding that “the government gets on with the job of insulating Britain’s homes”. Since then, a series of similarly controversial actions has catapulted the issue of insulating and heating homes into the public consciousness.

While there has been debate about whether such a radical form of protest is justified, the fact is that UK homes emit around one fifth of all UK's total carbon emissions. To reduce pollution from our households – and to meet the UK's net zero target - we rapidly need to make homes more energy efficient and switch to greener heating systems such as heat pumps. Retrofitting homes with insulation and low-carbon heating systems can be disruptive and expensive. But a convergence of emerging technologies and innovations such as robots, drones, digital twins and prefabrication could help make retrofits less disruptive and more cost-effective. Importantly, these technologies could soon be improving your home.

You could be warmed up, for example, with the help of Q-Bot’s small underfloor insulation robot, Greta Thunberg. While Q-Bot initially worked with local authorities, in 2021 the company branched out into private properties. Its robots can get into cramped spaces, scan and create a 3D map, and then spray insulation material where required. Normally this type of home improvement is difficult and disruptive, so it is often neglected. Q-Bot robots, however, have performed 2,000 installations in the UK so far, helping an average home cut around 700 kg of carbon emissions per year and reducing the yearly heating bill by £150.

Another key emerging technology is thermal imaging, which can identify where a home is leaking heat and design targeted retrofits. While infrared cameras are not new, companies such as IRT Surveys are strapping them on drones to assess roofs and hard-to-access areas, while others are even sending them into space. Satellite VU has raised about £20 million investment in 2021, and it plans to send thermal imaging satellites in 2022 to monitor energy efficiency at unprecedented scale.

Some homes will require a deep retrofit. The key idea of the whole-house approach from Energiesprong is prefabrication: manufacturing facades and roof panels off-site and transporting them to location for quick ‘wrap-around’ installation. In this way, Energiesprong aims to reduce costs and disruption to residents while transforming the building sector, just as Ford reshaped the automotive industry when it introduced assembly lines.

Unlike Ford Model T cars, however, every home is unique. This kind of mass customisation is enabled by technologies such as laser measurements, camera-equipped drones and 3D modelling software to digitally measure buildings and produce new, accurate exteriors. The insulation is combined with solar panels, battery storage, low-carbon heating, ventilation systems, sensors and smart controls resulting in net-zero homes and 100 percent reductions in carbon emissions.

This technology also opens the door to digital twins – realistic virtual representations of physical homes. By linking the digital twin to a detailed record of building and retrofit data, it’s possible to estimate retrofit costs more precisely and create a long-term plan of improvements which can be continued even if the property changes hands.

While digital twins are still new, enthusiasts are already building interactive replicas of their homes. With accurate digital twins, retrofitters could use augmented-reality goggles such as Microsoft’s HoloLens to overlay renovation plans onsite or visualise pipework behind the walls. More advanced digital twins will use machine learning to forecast and optimise energy usage on behalf of users (for example, by shifting the operation of tumble dryers to off-peak hours when electricity is low carbon and cheaper). They will also help heat providers spot and fix problems before the home becomes cold.

Ultimately, these technologies might be converging towards a new paradigm of ‘comfort as a service’ where instead of paying for energy or insulation, users will pay for the outcome – a comfortable home. By charging a subscription, like a phone plan, companies such as Sero aim to take the hassle away from consumers by deploying technologies and algorithms that optimise energy usage for a desired level of warmth and power the home using the cheapest and greenest energy.

With the growing number of successful pilots and case studies and the Mayor of London declaring a ‘retrofit revolution’, 2022 may be the year when these technologies reach a tipping point.

However, their upward trajectory is not assured, and Nesta’s recent analysis into such technologies found that low-carbon heating technologies – a critical part of the retrofit challenge – might be struggling to attract investment. As explained in the Innovation Sweet Spots report, deployment and scaling of technologies for decarbonising heating needs a more supportive policy environment and innovative business and financing models.

Looking to the year ahead, the signals are pointing towards the potential for these cutting-edge technologies to be harnessed to tackle a stubborn problem. Retrofit technologies can cut the UK’s carbon emissions – and they could also make the leap to zero carbon feel like a major improvement to our homes.