First Net Zero demonstrator home

A clergy house in a conservation area, with a previously low EPC rating, has been transformed into a demonstrator eco‑home, enabling the Diocese of Gloucester to research practical, cost‑effective ways to improve energy efficiency across its property portfolio.

“We’re trialling and monitoring the most efficient ways of running a low-carbon heating system in a real-world setting,” said Colin Scorer, Head of Property for the Diocese of Gloucester. “Currently, it’s being used as a working demonstrator, but when we begin to roll this out at a larger scale, we can use it to show clergy what these homes are like to live in and explain clearly how the systems work.”

The project is a reflection of the role clergy housing plays in enabling mission and ministry across the diocese. “A survey conducted in September 2025 indicated that most clergy view their accommodation as part of their mission,” said Erica Siddall, Strategic Net Zero Carbon Lead for the Diocese of Gloucester. “Greening our property portfolio will allow clergy to live more in line with their values. We believe it will also make posts more attractive to potential candidates, in a time of high vacancy rates across the country.”

The demonstrator home, located in Redmarley D’Abitot in the Forest of Dean, has been fitted with cavity wall insulation and improved roof insulation, an air source heat pump, a new heating system and hot water cylinder, upgraded photovoltaic (PV) solar panels installation by adding battery storage, an energy diverter for solar-powered hot water, and an electric vehicle charging point.

“The aim from the outset was to learn as much as possible from a challenging property,” said Colin. “The property was selected due to the problems it presented, but also due to it being vacant so the project could be undertaken without impacting the member of clergy and family. The challenges included a very poor EPC, being located in a conservation area, and having bats, which are a protected species. By tackling a complex project during vacancy it meant we could research, design, plan and project manage the demonstrator in slow time to understand the process properly, obtain best value and work out the right contractors to deliver the best outcome without the pressure of someone living there.

“We’re currently trialling the house and running the heating system as though someone is living there. We’re not using appliances such as cookers, showers or TVs, but the heating is being operated just as it would be in an occupied home, so we can understand the most efficient way to run it.

“We’ve also liaised with the utility supplier Octopus Energy and as a result have moved to moved to a new tariff that’s better suited to air source heat pumps. We’re hopeful that this will significantly reduce running costs. Prior to the works the property was graded E40 and post works, it has come in at a C76 which is a close to a B. This is a huge difference to the energy performance.”

The project has been supported through grant funding, including funding from Marshall’s Charity, Sylvanus Lysons Charity and the Boiler Upgrade Scheme, with the majority of funding coming from the national church’s Net Zero carbon programme, which supports dioceses on their sustainability journeys and will continue to do so beyond 2030. Diocesan Property Surveyors Chris Swioklo and Craig Smith played a huge part, Chris managing the project and Craig researching and implementing a 20% saving (zero rated VAT) for the net zero carbon works.

Erica said, “This first eco home is a great milestone, showing that decarbonisation can be achieved. Environmental credibility has also been shown to be a key factor in attracting young people to church, and the Diocese of Gloucester has so many pockets of great environmental practices.

“With government decarbonisation ambitions pushed back to 2050, we in the church are showing that there is no reason to wait that long. As a charity, we must focus on using our resources to the best possible purpose, and investing in clergy wellbeing is a great way of making the church in and around Gloucestershire more sustainable in the long run.”

The results will contribute to an upcoming guide that will set out practical, cost-effective and energy-efficient approaches to managing and running clergy housing.