Photo by Bethany Opler on Unsplash

The challenge of energy-efficient retrofit

In the UK, our homes account for about 30% of total energy consumption and about 20% of total carbon emissions. To have any hope of reaching the 2050 net-zero target, we must drastically cut domestic energy use, and decarbonise what remains. Most of the energy demand is for space and water heating, and we have an ageing and inefficient housing stock. We can’t completely replace existing homes, so we must upgrade them. To make our homes fit for the future, they must not only be low carbon, but resilient to climate change, attractive and desirable, and adaptable to the changing needs of society.

We can upgrade an existing property to net-zero emissions, but we can’t yet do it cost-effectively, in volume and at speed. We know the barriers to progress, and we need new approaches to increase demand and strengthen the supply chain.

Early in March 2020, I was at the Futurebuild exhibition and conference in London to chair a panel on “Building a market for energy efficiency: how demand for quality domestic retrofit is growing and why”.

We had three great speakers to explore growing the market and making sure industry can deliver:

Kate and Russell described projects funded by BEIS to create local retrofit supply chains, and Richard talked about the London Retrofit Accelerator programme.

Everyone shared some core ideas about the retrofit challenge:

  • The necessary deep retrofits are feasible
  • There is a great market opportunity
  • Excellent communication to both buyers and suppliers is vital
  • The focus must be on meeting customer needs
  • It needs to be a whole house plan, even if delivered in stages
  • Customers need to trust suppliers
  • There must be a performance guarantee

Each project takes a slightly different route to growing demand and building the supply chain.

Centre for Sustainable Energy and Futureproof – supporting early adopters

The CSE Futureproof project tries to work with the early adopters in the technology adoption curve. Customers who are ready and willing to invest. They do not want to be cold-called but actively involved and in charge. However, they need some hand-holding. They can’t deliver the whole project on their own. So these customers contact Futureproof who research the specific property and arrange surveys; anything from a simple EPC to a full SAP analysis. From that, a whole house plan develops that meets the client’s needs and pocket.

At the same time, Futureproof is working with SMEs to improve skills so that they can deliver these retrofits. They provide a training programme through Green Register covering all aspects of energy efficiency retrofits. Contractors who complete enough training modules get registered with Futureproof and are recommended to clients.

Getting contractors involved is hard. Many have full order books and no need for new and potentially more demanding markets. SMEs and sub-contractors cannot easily afford the time to take courses. If they are not working, they are not getting paid. And the training does not lead to a nationally recognised certification, only the approved provider list for Futureproof.

Despite the difficulties, Futureproof is steadily growing the number of trained providers for their enthusiastic customer base.

Retrofitworks – using retrofit coordinators

“This is the biggest engineering project the UK has ever seen” Russell Smith

Retrofitworks are developing their approach through the Warmer Sussex project. Retrofitworks is a cooperative that brings together advocate groups, such as Citizens Advice, providers and retrofit coordinators to be a one-stop-shop for clients.

Local advocate groups provide a point of access for potential customers and help with advice and guidance. They are neutral and more trusted by the community than many commercial operations. Retrofit coordinators support the customer throughout their journey, providing oversight and ensuring that the right work is done at the right time in the right way. The scheme encourages providers to expand their skills and the range of work they carry out to deliver a better service. For example, installing underfloor insulation is cheap and easy, but lifting floorboards is expensive and disruptive. So plumbers and electricians should install the insulation whilst doing other work to avoid doubling the cost and hassle.

The whole house plan is at the centre of their model. Houses must be renovated systematically and in big chunks to reach the net-zero targets, without any upgrade blocking the pathway to the next step. And since every home is different, we need a specific plan that shows everything that must be done by 2050 and in what order. Retrofitworks are developing an online tool to help model individual properties and develop that long-term whole-house plan.

Trust is vital. Householders must believe that the work has been well done and will deliver. Retrofitworks make use of the TrustMark scheme to provide confidence. Communications with the customer need to be authentic, show the value with rigour and logic, and see things from the consumer perspective.

In Russell’s view, developing a skilled workforce is one of the major challenges. As he says, “this is the biggest engineering project the UK has ever seen”, and he worries that colleges are giving people the wrong training for the future market.

Building the market in social housing with the London Retrofit Accelerator

“If I can get you a self-funding investment which will have a return… At a price that affords itself from savings in energy and repair and maintenance bills… At a price that is guaranteed and which is guaranteed to perform… Do you want it?” Richard McWilliams

The London Retrofit Accelerator has a slightly different objective. Its focus is social housing and driving demand; showing that it is possible to retrofit an old and diverse stock to be both warm and desirable. Richard identified three demand-side problems:

  • The available solutions don’t work
  • It is way too expensive; even for social landlords with their clear community purpose
  • It is hard to get suppliers who will stand by their work and guarantee performance

We need approaches that the customer can trust, make economic sense and are guaranteed to work.

A key concept in the accelerator is the energy performance contract. You don’t buy individual components and fuels; you buy a comfort plan. Just like a mobile phone, you buy a bundle of services for a monthly fee that gives you a guaranteed performance. You care about the result, not the process. The accelerator uses the Energiesprong approach to retrofit; developed in the Netherlands and tested in the UK in Nottingham and Maldon. Using industrialised construction methods, it works for many house types and guarantees performance and total cost of ownership for up to 40 years.

The shift to energy performance contracts and comfort plans with guarantees makes it much easier for a social landlord to build a viable business case. Richard McWilliams said the aim was a pitch that made immediate sense to decision-makers:

“If I can get you a self-funding investment which will have a return… At a price that affords itself from savings in energy and repair maintenance bills… At a price that is guaranteed and which is guaranteed to perform… Do you want it?”

The programme starts with 1,000 fully funded demonstrator homes. They have a definite route to 10,000 homes, and 100,000 are possible in London alone. This is the kind of scale-up that can dramatically cut costs. Manufacturing consultancies are being brought into the project to help drive down the learning curve. Reducing costs by 50% from where they stand today is the minimum target.

The problems of deep retrofit are no longer technological. We know that we can retrofit existing properties to extremely high levels of performance and desirability. These three projects, and others, are pioneering ways to:

  • Support the early adopters
  • Build consumer confidence
  • Encourage and strengthen the supply chain
  • Guarantee delivery and performance
  • Make the economic case

With the focus now on growing demand and creating a robust and trusted supply chain, deep retrofit is moving closer to the mainstream. With 27m homes to retrofit to net-zero by 2050, we are going to need it!

Let’s Make our Homes More Energy-Efficient and Desirable
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7 thoughts on “Let’s Make our Homes More Energy-Efficient and Desirable

  • 10/06/2020 at 3:30 pm

    It is an even greater problem to retrofit a Grade II* listed building. The first and pssobly source of the greatest loss is drafts. The second is ingle glazing. Finally there are no wall cavities and often the top floor is an attic so no space to insulate easily. The conservation department at Bath Cith council has written a helpful book – “Warmer Bath” but not all towns agree (with it)

    • 11/06/2020 at 10:41 am

      Yes, not only is there a problem with listed buildings, there are conservation areas and older buildings of certain types.

      There are some technical solutions available for some of the difficulties. Thin vacuum insulated double-glazing can be installed in traditional sash window frames. External insulation, “throwing a duvet over the whole house”, can tackle solid walls and the low roofline and lack of attic space in many traditional rural homes. Unfortunately, none of it is cheap at the moment.

      I feel we should start with the high volume, easy properties and work our way up to the difficult to treat and protected properties. Getting the volume up will bring new solutions to the market, build experience and reduce costs. That will help with the diminishing number of more complex buildings. The Warmer Bath guide is excellent and the Centre for Sustainable Energy does good work.

      • 11/06/2020 at 12:53 pm

        The glory of this building is the front face. I don’t think there is a suitable “blanket” that would not detract from it’s looks. It is interesting to hear that vaccum double glazed units can fit in sashes, however they, as yet, don’t get past conservation (historic environment) officers.

        • 12/06/2020 at 8:58 am

          I know. We have to find ways to effectively insulate historic buildings without trashing the very things we value them for.

          Historic England has some useful guidance. The BRE did some interesting work renovating a Victorian stable block using vacuum insulated panels and aerogels. These are much thinner than conventional insulation and can be used on inside walls without taking too much space.

          The vacuum insulated glazing has been used in some restorations of historic buildings. I think a lot depends on the local officers.

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