ANALYSIS  ⁄  PLANNING & PLACE

Exeter net zero housing revolution takes root in Chestnut Avenue

Exeter City Council is taking exploratory steps from talking about a zero carbon future to delivering one with a pilot housing project in Wonford.

Exeter city council  Net zero exeter  Climate crisis  Housing crisis  Retrofit  Planning policy 

The green shoots of a net zero housing revolution are to be found on Chestnut Avenue, in Exeter’s Wonford housing estate, where six of the city’s 5000 council-owned homes have been chosen to pilot a new approach to transforming existing houses into energy efficient, low maintenance homes.

The pilot has been developed by the city council in partnership with others including a company called Energiesprong UK. “Energiesprong”, which translates literally as “energy jump”, is the trade name of a commercial process for retrofitting existing houses to net zero carbon standards that is already well-established in the Netherlands.

As the Energiesprong concept arrives in the UK, with projects for Nottingham and Exeter councils and a housing association in Essex, the pilot puts Exeter among the front-runners on the long march to a net zero carbon future.

Exeter net zero carbon housing pilot project in Chestnut Avenue

Retrofitting existing housing stock to eliminate the residential sector’s contribution to climate-changing carbon emissions is critical. The latest figures show that residential property accounts for 18% of the UK’s total CO2 emissions, a proportion that has risen steadily over the past ten years as the business and energy supply sectors have made more rapid progress in decarbonising.

Averaged UK figures show that space heating is the dominant driver of energy consumption in existing homes, making up 63% of annual energy consumption, followed by hot water demand (17%) and appliance demand (13%).

So, to meet Exeter City Council’s target of reaching net zero carbon emissions by 2030, urgent action is required to transform the city’s 50,000 homes.

The Chestnut Avenue pilot is both a demonstration of what retrofitting can achieve and, crucially, a source of learning to inform future investment decisions on a wider programme.

Exeter net zero carbon housing pilot project in Chestnut Avenue in Wonford

The Energiesprong concept is simple enough. A new outer shell is placed over an existing house. All the parts are precision-made in a factory before being brought to the conversion site. Wall panels are manufactured with integrated windows and doors, and are pinned directly to the existing outer walls. Roof tiles are replaced by a lightweight covering on top of which solar panels are laid together like tiles to keep the rain out.

The finished conversion requires no gas supply, and guarantees minimum temperatures and markedly reduced energy bills. The Green Alliance has produced a report which describes the process in more detail and assesses its potential.

With an experienced contractor a single house can be converted in as little as a day. However, while the six Chestnut Avenue houses selected for the pilot are arranged in a row of three adjacent semi-detached buildings, and all in council ownership, the pioneering nature of the project, combined with December’s wet weather, meant it has taken nearer four months to convert them.

Exeter net zero carbon housing pilot project external cladding and solar roof closeup

Ian Hutchcroft from Energiesprong UK recently delivered a seductive sales pitch to a thinly attended meeting of the city council’s Strategic Scrutiny Committee. He said three key conditions need to be met for the industry to take off in the UK.

First, a radical change in the purchaser-contractor relationship is required, from one in which the purchaser specifies a lot of detail to one where the purchaser specifies the outcomes to be achieved and leaves it to the supplier to decide how to achieve them.

Second, a shift to lower energy costs for tenants, because they need to consume less energy, is needed to allow a higher proportion of total housing payments to go to the landlord, in this case the council, to build up capital for future retrofits.

Third, the market for retrofits must become sufficiently large to encourage investment in the capacity to manufacture the parts needed for conversions at scale, thus reducing costs.

Exeter net zero carbon housing pilot project Mi-Space sign

The Chestnut Avenue retrofit is being carried out by Mi-space, an arm of the West Country-based Midas Group. But the project’s scale is tiny compared to the cost-efficient volumes needed to lower prices enough to persuade private sector landlords and owner occupiers, as well as councils and housing associations, to pay for conversions on a significant scale.

The Dutch experience was that institutional landlords needed to club together to create a sufficiently large customer base to justify the investments in manufacturing that are required. In the UK co-operatives could also be established to help owner-occupiers and private landlords take advantage of such economies of scale.

The principle is that the conversions pay for themselves through reduced energy and maintenance costs. But capital is needed upfront. Exeter has 50,000 houses of which only 10% are owned by the council. The city’s chief executive, Karime Hassan, tweeted after the scrutiny meeting that retrofit has the potential to help meet the city’s aim to be carbon neutral by 2030, but that scaling up from the pilot would be a challenge.

Exeter net zero carbon housing pilot project Karime Hassan tweet

It’s not only money that could hold back a programme like this. Owner-occupiers will need to decide whether they will stay in their homes long enough to benefit from the payback on the capital outlay, and older people may decide it’s not worth it.

Will private sector landlords, who currently simply pass on energy costs to their tenants, consider conversions value for money? Will the UK’s profit-driven construction industry be prepared to take on new types of outcome-based contract requiring 30-year guarantees? Will the government be prepared to toughen up building regulations to force house builders to adopt Passivhaus or similar standards and apply them retrospectively over time?

The benefits of major retrofitting programmes appear substantial, not only in terms of meeting our carbon targets but also because they create badly-needed new jobs in the manufacturing and construction sectors to replace those displaced from climate-hostile industries.

Whether Exeter adopts the Energiesprong model or something similar, the time available to convert the city’s existing housing stock is short. Council officers are enthusiastic about the Chestnut Avenue pilot, but they know that they, as well as councillors, will have to make hard-headed decisions on the way forward.

Initial conclusions from the pilot project are expected by Easter 2020.


 is a contributing editor of Exeter Observer.

Exeter in brief
Exeter in brief

The police inspectorate says DEVON AND CORNWALL POLICE must make urgent improvements after it was found to be inadequate in three of nine areas including responding to emergency and non-emergency calls and managing registered sexual and violent offenders.
Its assessment found two other areas required improvement while two more were graded “good”. A new chief constable was appointed in December after the force was placed under enhanced inspectorate monitoring last year.

DEVON COUNTY COUNCIL is consulting on its draft Exeter Local Cycling and Walking Infrastructure Plan, which is already nearly six years late, until the end of March.

UNIVERSITY OF EXETER staff have resumed strike action over pay, pensions and working conditions alongside Exeter school teaching staff with dozens more strike days planned during February and March.

EXETER CITY FUTURES published the agenda for its last board meeting on 30 January, two months after the meeting was held. It says it is “committed to being completely transparent and open about the things that are discussed at board meetings”. No minutes were included.

New figures show that 2.2 million people used EXETER CENTRAL RAILWAY STATION in the year to March 2022, making it the 155th busiest of 2,569 UK railway stations and (slightly) busier than Exeter St David’s.

DEVON COUNTY COUNCIL is not making sufficient progress with its children’s services since they were judged inadequate in January 2020 according to the latest Ofsted monitoring report which found that key areas still require significant change and serious issues remain.

The opening of MARSH BARTON RAILWAY STATION has been delayed yet again, to “this spring”, putting project completion more than six years behind schedule.

EXETER CHIEFS rugby club has reintroduced its offensive “tomahawk chop” chant during games at Sandy Park despite seeking to rehabilitate its reputation over misappropriation of Native American imagery.

The UNIVERSITY OF EXETER has submitted detailed plans for its 1,700 bed West Park redevelopment of 50,000m2 of student accommodation.

The police inspectorate says DEVON AND CORNWALL POLICE must make urgent improvements after it was found to be inadequate in three of nine areas including responding to emergency and non-emergency calls and managing registered sexual and violent offenders.
Its assessment found two other areas required improvement while two more were graded “good”. A new chief constable was appointed in December after the force was placed under enhanced inspectorate monitoring last year.

DEVON COUNTY COUNCIL is consulting on its draft Exeter Local Cycling and Walking Infrastructure Plan, which is already nearly six years late, until the end of March.

UNIVERSITY OF EXETER staff have resumed strike action over pay, pensions and working conditions alongside Exeter school teaching staff with dozens more strike days planned during February and March.

EXETER CITY FUTURES published the agenda for its last board meeting on 30 January, two months after the meeting was held. It says it is “committed to being completely transparent and open about the things that are discussed at board meetings”. No minutes were included.

New figures show that 2.2 million people used EXETER CENTRAL RAILWAY STATION in the year to March 2022, making it the 155th busiest of 2,569 UK railway stations and (slightly) busier than Exeter St David’s.

DEVON COUNTY COUNCIL is not making sufficient progress with its children’s services since they were judged inadequate in January 2020 according to the latest Ofsted monitoring report which found that key areas still require significant change and serious issues remain.

The opening of MARSH BARTON RAILWAY STATION has been delayed yet again, to “this spring”, putting project completion more than six years behind schedule.

EXETER CHIEFS rugby club has reintroduced its offensive “tomahawk chop” chant during games at Sandy Park despite seeking to rehabilitate its reputation over misappropriation of Native American imagery.

The UNIVERSITY OF EXETER has submitted detailed plans for its 1,700 bed West Park redevelopment of 50,000m2 of student accommodation.

More Analysis
Lottery graphic

COMMUNITY & SOCIETY

Council lottery operator to take cut from local charitable donations

Decision to promote gambling as "incentivised giving" plays down risks without assessing potential impacts or evidencing claimed benefits, disrupting relationships between community and voluntary sector organisations and supporters.

Exeter Development Fund workshop presentation October 2021

DEMOCRACY & GOVERNANCE

Exeter City Futures falsely claims development fund documents disclosed under FOI legislation

Senior council director puts company on collision course with Information Commissioner's Office as significant governance failings emerge after councillors and public kept in dark over Liveable Exeter financing scheme proposals.

Exeter City Council 2020-21 external audit report cover

DEMOCRACY & GOVERNANCE

Exeter City Living put council at "significant financial risk" after £2.2 million loss in first two years

Missing business plan, lack of transparency and conflicts of interest among senior council directors prompt board resignations and governance review at council-owned and funded company.

All Analysis
News
Exeter empty and second homes by council tax band October 2022 bar chart

PLANNING & PLACE

Exeter has more empty and second homes than built in city in past two years

Council tax premium proposals that aim to raise additional revenue from underused housing stock might also encourage return to residential occupancy.

University of Exeter students based at Streatham & St Luke's campuses 2021-22 & 2022-23 table

PLANNING & PLACE

30,000 students based at Exeter university campuses in 2022-23

Freedom of information request reveals significant drop on last year with postgraduate students accounting for 58% of fall in numbers.

Devon County Council headquarters at County Hall

DEMOCRACY & GOVERNANCE

Underperforming county council children's services to receive nearly half of proposed spending increases

Details of simultaneous £50 million 2023-24 spending reductions not yet published as finance director cites service delivery "re-prioritisation".

All News
Comment
Co-living - discover a new way to rent

PLANNING & PLACE

Council development levy changes are insufficiently evidenced and don't meet city infrastructure needs

Exeter City Council and Liveable Exeter partners impose faulty typology driven by policy objectives while ignoring new local plan, evidence base and statutory funding statement and excluding residential and retail charges from review.

Exeter city centre retail area map 2017 and 2022 CDRC data

CLIMATE & ENVIRONMENT

Is the grass really greener in Exeter city centre?

Academic research placing Exeter retail area at top of green space table was nationally reported, locally misrepresented then repurposed as booster fuel by local politicians overlooking study's social justice focus.

Exeter City Council outline draft local plan site allocations crop

PLANNING & PLACE

Will council seek investment zone status for Liveable Exeter sites?

Government growth plans combine tax breaks with planning deregulation, putting affordable housing provision and environmental protections at risk with little evidence that promised investment zone benefits would result.

All Comment
On our radar
All topics

ACCOUNTABILITY & TRANSPARENCY ACCOUNTABILITY & TRANSPARENCY ACCOUNTABILITY & TRANSPARENCY   AIR QUALITY AIR QUALITY AIR QUALITY   COP26 COP26 COP26   COVID-19 COVID-19 COVID-19   CITYPOINT CITYPOINT CITYPOINT   CLIFTON HILL SPORTS CENTRE CLIFTON HILL SPORTS CENTRE CLIFTON HILL SPORTS CENTRE   CLIMATE CRISIS CLIMATE CRISIS CLIMATE CRISIS   CO-LIVING CO-LIVING CO-LIVING   CONGESTION CONGESTION CONGESTION   COUNCIL TAX COUNCIL TAX COUNCIL TAX   CROWN ESTATE CROWN ESTATE CROWN ESTATE   CYCLING & WALKING CYCLING & WALKING CYCLING & WALKING   DEMOCRATIC DEFICIT DEMOCRATIC DEFICIT DEMOCRATIC DEFICIT   DEVON CARBON PLAN DEVON CARBON PLAN DEVON CARBON PLAN   DEVON COUNTY COUNCIL DEVON COUNTY COUNCIL DEVON COUNTY COUNCIL   DEVON PENSION FUND DEVON PENSION FUND DEVON PENSION FUND   EAST DEVON DISTRICT COUNCIL EAST DEVON DISTRICT COUNCIL EAST DEVON DISTRICT COUNCIL   EXETER AIRPORT EXETER AIRPORT EXETER AIRPORT   EXETER CATHEDRAL EXETER CATHEDRAL EXETER CATHEDRAL   EXETER CITY COUNCIL EXETER CITY COUNCIL EXETER CITY COUNCIL   EXETER CITY FUTURES EXETER CITY FUTURES EXETER CITY FUTURES   EXETER CITY LIVING EXETER CITY LIVING EXETER CITY LIVING   EXETER COLLEGE EXETER COLLEGE EXETER COLLEGE   EXETER CULTURE EXETER CULTURE EXETER CULTURE   EXETER DEVELOPMENT FUND EXETER DEVELOPMENT FUND EXETER DEVELOPMENT FUND   EXETER EXTINCTION REBELLION EXETER EXTINCTION REBELLION EXETER EXTINCTION REBELLION   EXETER LIVE BETTER EXETER LIVE BETTER EXETER LIVE BETTER   EXETER LOCAL PLAN EXETER LOCAL PLAN EXETER LOCAL PLAN   EXETER PHOENIX EXETER PHOENIX EXETER PHOENIX   EXETER PRIDE EXETER PRIDE EXETER PRIDE   EXETER SCIENCE PARK EXETER SCIENCE PARK EXETER SCIENCE PARK   EXETER ST DAVID'S EXETER ST DAVID'S EXETER ST DAVID'S   EXETER TRANSPORT STRATEGY EXETER TRANSPORT STRATEGY EXETER TRANSPORT STRATEGY   EXETER CITY CENTRE EXETER CITY CENTRE EXETER CITY CENTRE   FREEDOM OF INFORMATION FREEDOM OF INFORMATION FREEDOM OF INFORMATION   FRIDAYS FOR FUTURE EXETER FRIDAYS FOR FUTURE EXETER FRIDAYS FOR FUTURE EXETER   GENERAL ELECTIONS GENERAL ELECTIONS GENERAL ELECTIONS   GUILDHALL GUILDHALL GUILDHALL   HARLEQUINS HARLEQUINS HARLEQUINS   HEART OF THE SOUTH WEST LEP HEART OF THE SOUTH WEST LEP HEART OF THE SOUTH WEST LEP   HOUSING CRISIS HOUSING CRISIS HOUSING CRISIS   LGBTQIA+ LGBTQIA+ LGBTQIA+   LIVEABLE EXETER PLACE BOARD LIVEABLE EXETER PLACE BOARD LIVEABLE EXETER PLACE BOARD   LIVEABLE EXETER LIVEABLE EXETER LIVEABLE EXETER   LOCAL INDUSTRIAL STRATEGY LOCAL INDUSTRIAL STRATEGY LOCAL INDUSTRIAL STRATEGY   LOCAL ELECTIONS LOCAL ELECTIONS LOCAL ELECTIONS   MAKETANK MAKETANK MAKETANK   MARSH BARTON MARSH BARTON MARSH BARTON   MET OFFICE MET OFFICE MET OFFICE   MID DEVON DISTRICT COUNCIL MID DEVON DISTRICT COUNCIL MID DEVON DISTRICT COUNCIL   NET ZERO EXETER NET ZERO EXETER NET ZERO EXETER   NORTHERNHAY GARDENS NORTHERNHAY GARDENS NORTHERNHAY GARDENS   OXYGEN HOUSE OXYGEN HOUSE OXYGEN HOUSE   PARIS STREET PARIS STREET PARIS STREET   PARKING PARKING PARKING   PENINSULA TRANSPORT PENINSULA TRANSPORT PENINSULA TRANSPORT   PLANNING POLICY PLANNING POLICY PLANNING POLICY   PRINCESSHAY PRINCESSHAY PRINCESSHAY   PROPERTY DEVELOPMENT PROPERTY DEVELOPMENT PROPERTY DEVELOPMENT   PUBLIC CONSULTATION PUBLIC CONSULTATION PUBLIC CONSULTATION   PUBLIC HEALTH PUBLIC HEALTH PUBLIC HEALTH   PUBLIC REALM PUBLIC REALM PUBLIC REALM   PUBLIC TRANSPORT PUBLIC TRANSPORT PUBLIC TRANSPORT   RAMM RAMM RAMM   REFUSE & RECYCLING REFUSE & RECYCLING REFUSE & RECYCLING   RETROFIT RETROFIT RETROFIT   RIVERSIDE VALLEY PARK RIVERSIDE VALLEY PARK RIVERSIDE VALLEY PARK   ROYAL DEVON NHS TRUST ROYAL DEVON NHS TRUST ROYAL DEVON NHS TRUST   SIDWELL STREET SIDWELL STREET SIDWELL STREET   SOUTH WEST EXETER EXTENSION SOUTH WEST EXETER EXTENSION SOUTH WEST EXETER EXTENSION   SOUTH WEST WATER SOUTH WEST WATER SOUTH WEST WATER   SOUTHERNHAY SOUTHERNHAY SOUTHERNHAY   SPORT ENGLAND LOCAL DELIVERY PILOT SPORT ENGLAND LOCAL DELIVERY PILOT SPORT ENGLAND LOCAL DELIVERY PILOT   ST SIDWELL'S COMMUNITY CENTRE ST SIDWELL'S COMMUNITY CENTRE ST SIDWELL'S COMMUNITY CENTRE   ST SIDWELL'S POINT ST SIDWELL'S POINT ST SIDWELL'S POINT   STAGECOACH SOUTH WEST STAGECOACH SOUTH WEST STAGECOACH SOUTH WEST   STUDENT ACCOMMODATION STUDENT ACCOMMODATION STUDENT ACCOMMODATION   TEIGNBRIDGE DISTRICT COUNCIL TEIGNBRIDGE DISTRICT COUNCIL TEIGNBRIDGE DISTRICT COUNCIL   UNIVERSITY OF EXETER UNIVERSITY OF EXETER UNIVERSITY OF EXETER  

More stories