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December 7, 2022

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7 lessons for unlocking whole house retrofit at scale – meet the #RetrofitDisruptors

Shaking up retrofit with the Mayor of London’s Retrofit Accelerator – Homes Innovation Partnership

The construction industry has an opportunity to change the way we retrofit to meet the scale, speed and cost required for the climate emergency and millions of people experiencing fuel poverty.

The Mayor of London’s Retrofit Accelerator – Homes programme is designed to do just this by helping to transform the way London upgrades its ageing and energy-inefficient housing to create warm, affordable and ultra-low carbon homes.

As part of this, nine social housing providers, seven of which are based in London and four UK building firms, along with a network of suppliers, are working together to stimulate a new market for whole house retrofit across the UK and reduce costs. This is known as the Mayor of London’s Retrofit Accelerator-Homes Innovation Partnership (RA-HIP).

Meet the UK building firms disrupting the status quo

These four UK building firms – known as solution providers - are delivering their retrofits using the Energiesprong approach to whole house retrofit. As part of the RA-HIP they are part of a ‘Collaboration Hub’ with the social housing providers to foster shared learning.

From collaborating with competitors to pioneering industrialisation and guaranteeing energy performance long-term, they are going against the grain in the sector and learning lessons that can be shared across the whole industry.

It’s been a journey, and while there’s still far to go, we’re seeing progress. What are the RA-HIP partners doing differently, what have they learned and why do they think these new and disruptive tactics will help the UK unlock a functioning, self-financing whole house retrofit market?

1. Collaborate with competitors

I’ve been in the sector for 25+ years and we talk about it a lot, but this is probably the only example I can give in my career where we have truly collaborated with competitors.” Vicky Fordham-Lewis, Managing Director of Osborne Property Solutions.

It may be in the name, but true collaboration didn’t necessarily come naturally to the four solution providers in the Collaboration Hub – with Andy Merrin, Director of Innovation and Decarbonisation at United Living likening the first meeting to a poker game: “who’s going to show their hand first?

But as the project progressed, it became easier as they realised that - from communicating lessons to sharing suppliers – this transparency was only going to help, not hinder, their progress.

We're not going to reach anywhere near the scale we need if don't collaborate,” says Andy, with Vicky adding, “There is more than enough work to go around. And actually, if we work together, we'll just do it better and more efficiently for the benefit of the customer.”

2. Innovate and industrialise for scale

We're really investing our time and effort into challenging the way that we've done projects in the past and looking at how industrialisation can make them quicker, more efficient and delivered at scale.” AJ Eaton, Director of Decarbonisation and Energy Solutions at Bell Group UK.

Delivering whole house retrofit at the scale and speed we need will require a shift in how it’s done.

Traditional onsite insulation methods can be slow and often result in lower performance compared to a factory-manufactured panels which is why the solution providers in the Mayor of London’s RA-HIP are moving towards an industrialised approach. As Vicky points out: “If just half of UK homes had a panelised solution that would definitely speed up roll out of whole house retrofit, wouldn’t it?”

There are also further co-benefits. Koré Mason, Associate Director, Consulting UK at Turner & Townsend – which is helping deliver RAH-IP – states: “developing a greater pipeline for manufactured solutions will help us all to not only deliver a higher quality standard of retrofit, but also increase productivity within the sector and tackle some of the challenges that we've been facing around labour shortages and cost increases over recent years.”

And there’s plenty of inspiration out there – Andy Merrin highlights that “we can’t do things the way we’ve always done them…we need to embrace innovations that are outside the industry, looking at how car manufacturing or mass-produced solutions have reduced their cost.”

3. Guarantee energy performance

The Energiesprong model is a real shift in how retrofit is approached.” Emily Braham, Head of strategy and operations at Energiesprong UK

One of the innovations that underpins the Energiesprong model is that the solution provider signs a performance guarantee, ensuring that the energy the home uses and generates are in line with the approved design.

The high performance has to be guaranteed by the new role that's been developed, the solution provider. And the solution provider designs, delivers and then guarantees that performance for a long term, meaning they have to monitor the actual performance of the home once the work is completed” explains Emily.

This is one of the biggest changes to the status quo that the solution providers have faced says Andy Merrin: “It’s quite new to the industry and quite new to our teams in terms of looking at risks and liabilities, because these retrofits are going to exist for 20, 30 years. So how can we mitigate that risk? By getting the design correct, planning it correctly at the offset, and making sure it's delivered in terms of a PAS2035 compliance scheme.”  

4. Nurture the supply chain with a strong pipeline

I would say the biggest concern we have that we need to deal with in this industry is supply chain and resource.” Ben How, Business Innovations Manager, Equans.

There’s a large mission ahead of us says Ben, adding: “And with the supply chain as it is, that's a task that won't happen unless we can actually help support smaller SMEs and get people into the industry.”

Central to RA-HIP is the drive to develop the whole UK supply chain for products like offsite manufactured insulated panels and energy modules to increase scale and reduce cost to unlock the market for whole house retrofit.

And the collaboration at the heart of the project is fundamental to this. By combining demand, the solution providers are showing bigger buying power – helping create a flourishing supply chain for a strong pipeline – resulting in a runway that isn’t subject to the current stop-start challenges.

Several solution providers also mentioned the need for government to signal long-term commitment for energy efficiency to allow UK’s supply chain and providers of net-zero retrofit time to gear up and invest in the innovation we need.

5. Rethink resident engagement

My advice to other organisations who are looking to achieve net-zero retrofit to their current housing stock would first and foremost be: there will never be enough customer engagement.” Vicky Fordham-Lewis, Managing Director at Osborne Property Solutions

Tenant engagement can make or break a scheme. From dropouts to confusion about how to use their home’s new technologies, getting retrofit projects off the ground and performing well long-term hangs on tackling these challenges.

Vicky says: “If we want our customers to have these services deployed in their homes and have these measures that actually work and are adopted, we need to be collaborating and working with them and talking them through the entire process from design and inception all the way to handover and demonstration.”

6. Develop diversity

We need to make it appealing for different types of people to come into the industry. We need more women. We need people of different ethnicities. We must capitalise on the energy and enthusiasm of the people that want to solve our climate crisis because they’ll be our champions of the future.” Emily Braham

As well as training existing staff, Bell Group’s AJ Eaton was also emphatic on the need to engage younger generations interested in climate change with the sector to tackle the skills gap and increase the volume of people who can deliver these schemes.

This is the perfect opportunity to open the sector up and draw on new perspectives – something that construction desperately needs says Emily. Consider how you can encourage new people into the industry she says – adding that retrofit is perfect for attracting talent: “manufacturing, digitalisation, offsite construction - these are much more exciting things to bring young people in.

7. Make iterative learning the industry standard

It's a huge learning curve we're all going on.” Andy Merrin, Director of Innovation and Decarbonisation at United Living Property Solutions

Some things have worked. Some things haven’t. But we should embrace that things won’t always go well – and make sure these lessons aren’t being lost says Andy: “How do we capture this information? Because it's the failures we need to focus on and understand why we went wrong.”

Rolling out whole house retrofit at scale and at speed will require the industry to be more honest and share learning widely. With the four solution providers in RA-HIP paving the way, it’s not escaped their attention that their valuable experiences could help prevent duplicated mistakes in the future.

I think because we need a repository for all the things we are learning now,” shares Vicky Fordham-Lewis, adding that: “once we've collected that, it needs to be easy to use and accessed for future projects and future partners that come on board. But also, there's the ability then to share that wider into manufacturing or subcontractor chain to make sure that they aren't repeating the same issues.”

Discover more insights into the work being done via the Mayor of London’s Retrofit Accelerator – Homes Innovation Partnership by checking out the full video interviews with the solution providers:

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The Retrofit Accelerator - Homes programme is funded on a 50:50 basis by the Mayor of London and the European Regional Development Fund (ERDF). The delivery partners, led by global professional services company Turner & Townsend, include Energiesprong UK and the Carbon Trust.