Transform-ER’s demonstrator home: From EPC D to A in four weeks - at half the cost
Transform-ER is a new integrated retrofit delivery model designed for social landlords and local authorities. Its first demonstrator home was completed in December 2025 on the Becontree Estate in the London Borough of Barking and Dagenham, taking the property from EPC D to A in four weeks and at roughly half the cost of comparable previous schemes. The local authority is now looking at using the model for a further 50 homes on the same estate.
Rethinking retrofit for speed, scale and quality
Transform-ER (Transform. Engage. Retrofit) emerged from Innovate UK's 2023 Net Zero Heat challenge lab. 13 industry experts - including BRE, Energiesprong UK and the Manufacturing Technology Centre – united to spend 22 months rethinking how retrofit is delivered to tackle the industry’s biggest barriers to scale, speed, quality and satisfied residents.
This included creating new digital tools for pipeline aggregation and portfolio assessment, finding new finance routes, innovating kits-of-parts solutions, rethinking resident engagement and forming ground-breaking contracting and procurement models.
An integrated model with one accountable partner
The project’s research and stakeholder engagement were clear: retrofit’s biggest challenges are not isolated operational problems, they are symptoms of systemic fragmentation. Poor landlord data prevents manufacturers from planning production.
Poor resident communication drives up drop-out rates. Procurement frameworks that don’t enable collaboration mean everyone carries more risk.
“I am very happy. The team were lovely and hardworking, and it was exciting to see my extra loft storage completed – something I’d requested.” Florina, a resident in the home.
The team took a systemic approach to creating a new retrofit delivery model that addresses this by integrating better data, kits-of-parts solutions, resident engagement and collaborative delivery under a single accountable partner - offering social landlords cost certainty and quality outcomes.
Transform-ER is now a Community Interest Company founded by four members of the original consortium - Bow Tie Construction, Energiesprong UK, KIN® and Planarific – with a mission to enable a thriving retrofit ecosystem that can deliver 1m home energy upgrades a year by 2030.
How it works in practice
The Becontree demonstrator was designed and delivered by Bow Tie Construction and funded by Innovate UK, Thames Freeport and delivery partners. It used Ultrapanel Building Technologies' next-generation external wall insulation (EWI) - an offsite-manufactured system using 3D scanning to configure panels precisely to each building. Because the system is installed externally, resident disruption is minimal; scaffolding was up for just three weeks.
Ventilation and M&E were fully integrated into the EWI system. A single low-energy central fan runs continuously, extracting air from the kitchen, bathroom, under-floor space and battery box. Solar panels and a battery complete the package, with a bespoke ventilated battery box in the back garden enabling easy maintenance and avoiding overheating risks.
The boiler had recently been replaced, so a heat pump was not installed – but the connection is there ready for when it is upgraded.
Rethinking delivery
One of the biggest shifts in delivery was how work was structured. Rather than treating the project as a single continuous run from start to finish, Bow Tie Construction split it into two distinct phases: a week of preparatory works, followed by a deliberate four-week buffer, and then the main works phase.
This allowed time to carry out all ground works and testing of existing electrics and plumbing to avoid any surprises during the main works phase. It also supported cost control with live design conversations run across four weeks of design and then refined after the prep phase – rather than discovering challenges once they were on site.
Retrofit done with residents, not to them
Transform-ER's approach to resident engagement is one of its most distinctive elements and was also supported by the two-phase approach. Rather than treating engagement as a box to tick, the team began with a genuine conversation about the challenges the resident was experiencing in her home - issues with rats, poor water pressure and inadequate storage.
All three could then be addressed within the retrofit scope. Holes were filled, the loft was boarded, and a new water pump installed. The lead contractor also took 20 minutes to fix a sticking front door – these low-cost interventions built trust, reduced the risk of drop-out and took pressure off the landlord.
Find out more about Transform-ER’s mission to rethink retrofit here.