9. Built Environment

Figure 9.1 shows the Energy Performance Certificate (EPC) rating of Devon’s homes. Government’s target is for as many houses as possible to be band C by 2035.³ In Devon this means upgrading two thirds of our homes (383,000) over the next 15 years, which is 25,500 homes per year – five times faster than Devon is currently installing cavity wall insulation.⁴

Figure 9.1 – Energy Performance Certificate Rating of Devon’s Residential Buildings.⁵

We need to go beyond the Government’s target and aim to retrofit every home to as close to Band A as possible by 2050. To achieve whole-house retrofit cost-effectively will require new approaches.⁶

The Committee on Climate Change (CCC) Further Ambition scenario for net-zero in 2050 requires a 25% reduction in energy demand in homes from insulation measures. Taking this fabric-first approach will facilitate the installation of heat pumps which, to be affordable to operate, need the building to be thermally efficient. In Devon we need to insulate:⁴ 

• All practicable lofts by 2022.
• All cavity walls, where appropriate, by 2030.
• 36,000 solid walls by 2030 and 109,000 by 2050.

Once homes have been made more efficient, we need to eliminate GHG emissions from their heating systems. Applying the CCC Further Ambition scenario to Devon will require:⁴ 

• 18,100 heat pumps in existing homes by 2030 and 344,000 by 2050. 
• 91,000 homes connected to retrofitted district heating. This distributes hot water, heated by centralised power plants, in a network of highly-insulated pipes to a collection of buildings. The heat source will be either large heat pumps or green hydrogen. This will be challenging due to the trenching required for the pipes and the high proportion of households needing to connect to the system to make schemes financially viable.
• The remaining houses (146,000) to be switched to either:
  • Green hydrogen (requiring the installation of hydrogen-ready boilers and national distribution infrastructure);
  • hybrid heat pumps (these could be appropriate for buildings on the gas network. Hybrid heating systems use a combination of a heat pump with a gas boiler. In this setup the heat pump provides the bulk of the base load while the gas boiler tops-up the heat requirement when demand is high);  
  • or biomass boilers.
• A small number of homes using direct electric heating (just 1,000 nationally, such as heritage homes unable to use heat pumps or hydrogen).
• All cooker replacements to be electric from 2030.

Nineteen percent of Devon’s homes are off-gas, compared to 16% nationally.⁴  Off-gas buildings with oil or liquified petroleum gas central heating can have a heat pump installed if the building has been made more efficient to heat. If this is not possible, a biomass boiler may be appropriate if there is space. Off-gas buildings without pre-existing central heating will either need to install radiators or warm air distribution systems to make use of a biomass boiler or a heat pump. Alternatively they could use direct electric heaters, but these are expensive to run as they have just 1/3 the efficiency of a heat pump. 

Heritage buildings present a particular challenge due to the need for continuous ventilation to reduce moisture build-up inside and to be sympathetic to any listed status or conservation area. Eliminating GHG emissions from these properties is possible but more costly. Given these challenges, the CCC’s Further Ambition scenario acknowledges that these buildings may not reach zero emissions until 2060. Whilst these buildings will be challenging to retrofit, when emissions are considered across the life of the building, retrofitting a heritage building will emit fewer GHGs than demolishing it and building a new one. But greater support for retrofit of heritage buildings is needed.

The materials and technologies required for retrofit produce GHGs in their manufacture and transportation but the resulting energy and GHG savings over the lifetime of the products results in in an overall reduction.⁹

The CCC Further Ambition scenario for net-zero in 2050 requires energy efficiency upgrades to achieve a 20% reduction in energy demand by 2030 and a 25% reduction by 2050. The technologies are not specified but Government is introducing a minimum efficiency standard of EPC band B by 2030 for privately-rented commercial buildings.¹⁸

It is assumed there will be 11,200 heat pumps in Devon’s non-residential buildings by 2030 and that heat pumps will meet 45% of heat demand by 2050.⁴ The rest will be met by low carbon district heating (particularly well suited to industrial estates where heat demand may be high), hydrogen and biomass. Roofs can also be used for solar photovoltaic panels.

Making best use of existing buildings and remodelling them where they are not suitable for modern needs must be favoured over demolition and new construction. Where they are necessary, the construction and operation of new buildings need to be net-zero as soon as possible. They need to be highly energy-efficient and use low-carbon heat sources from the outset to avoid a costly retrofit later – making a new home zero-carbon is around five times cheaper than retrofitting it later.¹⁰ We must consider district heating for new developments where the distribution pipes and energy centre can be designed in from the outset, particularly in locations where waste heat is available from industrial processes. 

But, just because the buildings are energy efficient does not mean that they will be used in an energy efficient manner. Building occupants must be supported to use new buildings and technologies properly.

About 10% of the UK’s GHG emissions are from the material extraction, manufacturing, transportation and end-of-life decommissioning of products required for new construction (referred to as embodied carbon)¹¹ and these make up 35-51% of a building’s total emissions over its lifetime. New buildings need to be net-zero not only in operation, but also in construction.

We can make energy savings in public and shared spaces through rationalising existing lighting and converting to LED technology. Progress has been made, but more can be done and faster.

Retrofitting a building with all the energy efficiency and low-carbon technology to achieve net-zero has high upfront costs (between £32k and £60k for a house depending upon house type) and can be disruptive, making it unattractive despite evidence that a home with an EPC band C is worth 5% more than a D-rated property.¹⁸ Retrofitting property needs to appeal to people so that social norms are changed and living and working in net-zero buildings becomes desirable. Tenants can be reluctant to carry out building improvements as they will not benefit from increases in value to the property, whilst landlords can be reluctant to act as they will not benefit from energy cost savings.

Making It Happen

An industry capable of delivering self-financing retrofit needs to be developed – whereby the costs are affordable and balanced by the benefits to the building occupants and/or owners – at scale to achieve the installation rate required.

Innovation

New models and technologies need to be nurtured. The Government is investing in heat pump innovation to make them smaller and easier to install so that by 2030 they will cost the same as a gas boiler. There will also be national trials of hydrogen heating ahead of Government decisions on its future role in net-zero in 2026.¹⁸ Government will be undertaking further testing during the 2020s to establish the costs, benefits, safety, feasibility, air quality impacts and consumer experience of using hydrogen for heating.¹⁹  

By using off-site manufacturing technology to produce a bespoke air-tight and insulated shell and energy upgrades for a specific building, the Energiesprong model minimises disruption and costs. This Dutch approach is being trialled in Devon by the Zero Energy Buildings Catalyst focussing on social housing where the volume of houses under the same ownership provides economies of scale to kick-start skills and the supply chain to drive down costs in future years. Energiepsrong uses the long-term energy and maintenance cost savings to repay the initial costs of the retrofit.²⁰

Finance

Greater financial incentives for retrofit are needed to encourage uptake. 

In 2020, the government funded research in East Devon, in partnership with the District Council, into how effective rebates on council tax and business rates would be on incentivising energy efficiency.²¹ A 50% subsidy towards energy efficiency installation, refunded over three years via tax rebates, was attractive to East Devon home owners and businesses and was supported by 71% of the Devon Climate Assembly (so long as there would be a simple and consistent way for the effect of energy efficiency improvements to be verified).²² The scheme delivery in East Devon alone would cost the UK tax payer £11.5m and would deliver £23m of installed measures. Piloting this approach needs further collaboration with government and the promotion of such a scheme could be implemented by the Devon Energy Efficiency Advice Service if it were deemed appropriate. 

Green mortgages offer favourable interest rates for people who choose to purchase an energy efficient home or commit to upgrading its energy performance. These are new products, which 72% of the Devon Climate Assembly thought should be developed further.²² These are the subject of the government’s Green Home-Finance Accelerator, launching in Autumn 2022, that is designed to overcome the high initial-development costs for lenders to make more products available.²³

Collective purchasing can also bring down costs – in 2021, Devon Solar Together bulk-ordered solar photovoltaic panels for domestic properties and achieved a cost-reduction of about 30%. 

The net-zero commitments of organisations, which will require carbon offset credits to achieve, could be used to fund retrofit activity. For example, a payment for carbon offsetting could fund the installation of insulation or a heat pump into a building, with the resulting carbon savings being owned by the organisation that funded the measure. The energy savings would benefit the bill payer. There are companies in Devon looking to setup this model.

Sell the Benefits

We don’t always expect an investment to pay for itself purely financially. For example, installing double glazing doesn’t pay back its purchase price in energy cost savings alone but is purchased at great expense to achieve the benefits of thermal comfort, reduced maintenance, security and noise insulation. The health and wellbeing benefits of living in a warm and net-zero carbon home need to be better communicated so that it becomes a social norm. Opening up the homes of those who have already installed new measures to show the benefits to others in a credible way can be a role for community organisations to help raise awareness locally. 

The Actions

B1. Expand whole-house retrofit by working with social landlords to aggregate their housing stock and collectively procure retrofit.

B2. Take opportunities to enhance and raise awareness about financial support available for people and organisations to retrofit their properties.

B3. Raise awareness of the co-benefits of living in net-zero homes.

Needing action beyond Devon

B4. Work with Government to encourage VAT breaks on retrofit activity and products. 

B5. Work with government to continue exploring the use of Council Tax and Business Rates to encourage energy efficiency upgrades of buildings.

Cosy Devon, the County’s home energy-efficiency partnership, has previously offered insulation for free, but found this did not increase take-up; non-financial support is also necessary. For example, the hassle of clearing out the loft deterred some from installing insulation, and households sometimes didn’t trust available support mechanisms. This issue becomes even more significant when it is applied to a whole-house retrofit that needs to involve designers and different trades people installing more invasive measures to a building. Commercial buildings are particularly problematic because there are many different types of construction and therefore require a tailored approach. 

Making It Happen

There is no central provision of advice and support in Devon to those that want to make building improvements to either homes or business premises. Government’s ‘Boosting Access for Small and Medium-sized Enterprises (SMEs) to Energy Efficiency Competition’ is finding innovative solutions to increase retrofit activity in business premises, which may develop approaches suitable for Devon.  

A county-wide energy advice service

Devon needs an energy advice service to increase confidence in building retrofit and make it easier. The service would:

1. Build on the services provided by community energy companies 
2. Provide people with an independent, whole-building energy assessment to make bespoke recommendations  
3. Encourage building improvements at trigger points e.g. kitchen, bathroom or workspace remodelling
4. Offer do-it-yourself guidance
5. Signpost to market offers of finance
6. Provide training to installers 
7. Recommend trusted retrofit installers
8. Coordinate the works
9. Undertake quality inspections of work completed
10. Keep abreast of innovative solutions emerging for SMEs

Sharing best practice for organisations

Devon Climate Emergency partners are reducing their emissions which includes retrofitting their buildings. The partnership should ensure experience is being shared with other large energy consumers in the County. 

The Actions

B6. Establish a Devon-wide energy advice service. 

B7. Keep abreast of innovative retrofit solutions emerging for businesses, pilot promising approaches and share experience with others.

Case Study 

RetrofitWorks 

RetrofitWorks offers a ‘one-stop-shop’ retrofit design and installation service. It is a co-operative which matches homeowners who want to retrofit their homes with local, quality-assured energy assessors and installers. It brings together three groups of stakeholders:

1. RetrofitWorks Advocates – organisations, such as community groups and local authorities, that represent potential customers. 
2. RetrofitWorks Practitioners – vetted organisations wishing to carry out retrofit advice, assessment, design, coordination, and installation. 
3. RetrofitWorks Associates – open to any organisation that wishes to formally support the co-operative. 

The RetrofitWorks’ approach ensures value for money for the property owner by creating competition amongst its practitioner members, and through economies of scale. Profits are returned to the cooperative membership, for example by providing discounted training programmes or funding for fuel poor households.²⁴

The Devon Climate Assembly considered ways of encouraging or requiring people to retrofit their homes, properties or business premises to reduce carbon emissions. Sixty-two percent of the Assembly were in favour of using regulation to require the upgrading of homes so long as: 1) There is recognition that buildings are not all the same; 2) the requirements target the poorest rated buildings first; and 3) their implementation does not increase inequality.²² 

Making It Happen

The Minimum Energy Efficiency Standard

Energy-inefficient housing puts residents at risk of fuel poverty due to the increased costs of staying warm. The Government brought in the Domestic Minimum Energy Efficiency Standard (MEES) Regulations to prohibit landlords from leasing property with an EPC below an E. Enforcement is the responsibility of local authorities’ Trading Standards services but no additional funding has been provided to do so. Furthermore, the cap on the financial contribution expected from landlords to improve the property is set too low to deliver meaningful energy efficiency measures.²⁵ These issues mean the MEES Regulations are not working effectively.²⁶

The majority of the Devon Climate Assembly (85%)²² were in favour of government making changes to the MEES Regulations to improve their effectiveness and making resources available to local authorities to enforce them. However, this needs care because a poorly designed scheme could increase rent payments and contribute to increasing existing inequalities. In 2021, government ran the Private Rented Sector MEES Compliance and Enforcement Funding Competition, which provided assistance to local authorities to build compliance and enforcement capacity and capability.²⁷ Exeter City Council and Teignbridge District Council were among the local authorities to win funding. 

Similar effectiveness and enforcement issues may apply to Government’s plans for privately-rented commercial premises to achieve EPC band B from 2030.¹⁸ 

Planning Permission

The Devon Climate Assembly (71%) supported using the development control system to require energy efficiency upgrades to the whole house at the time of adding an extension (including conservatories where these are not classed as permitted development). The Assembly stressed that the extent of the retrofitting should be proportionate to the size of the house and the extension.²²

Such measures have been used before elsewhere, most notably by Uttlesford District Council in Essex, in the mid-2000s but are no longer.²⁸ Introducing such a system in Devon may require national changes to legislation, which has evolved since Uttlesford’s pioneering example. 

The Actions 

B8. Evaluate the use of planning conditions to require energy-efficiency upgrades at the time of extending a home, and any other local regulatory opportunities that arise.

Needing action beyond Devon

B9. Work with Government to ensure effective minimum energy efficiency standards and that resources are available to enforce non-compliance.

B10. Work with government to explore additional mechanisms to require energy-efficiency upgrades.

Minimum standards for new buildings

The national Future Homes Standard will be introduced in 2025. This will ensure new homes produce 75-80% lower CO₂ emissions from their operational phase than required by 2013 Building Regulations. These homes will be “zero carbon ready” with high levels of energy efficiency and low-carbon heating so that as the electricity grid decarbonises they will achieve net-zero emissions. An interim uplift to the Building Regulations in 2021, to be implemented in 2022, will expect a 31% reduction in CO₂ emissions over current standards and will require rooftop solar photovoltaic panels covering 40% of the footprint of the home.²⁹

Government has acknowledged that planning policy and its own communications has caused uncertainty about whether local planning authorities can request that new homes exceed the minimum energy efficiency requirements of the Building Regulations. Helpfully, Government confirmed in 2021 that local planning authorities retain powers to set local energy efficiency standards for new homes.²⁹ 

In parallel, Government proposes to introduce the Future Buildings Standard from 2025 which will apply to the operation of non-domestic buildings. The specifications of this are still under development but the intention is to deliver highly efficient buildings using low-carbon heat. An interim uplift to standards in 2021 proposes a 27% CO₂ reduction over 2013 Building Regulations to help the industry prepare.³⁰

Often the real-life performance of a building does not meet its expected energy performance, meaning that buildings we believe are efficient, are not. Reasons include inadequate knowledge within design teams, poor installation of materials and inconsistencies within the design standards themselves.³¹ The Government has said it will reduce the performance gap by improving the accuracy of ‘as-built energy calculations’ and provide clearer information to building control bodies to encourage the right design choices.²⁹ 

There are no Government requirements to minimise embodied carbon emissions from new buildings but the CCC has made recommendations. The CCC expects 40% of new homes to be built with a timber frame (up from 30% in 2018) by 2050², which has less embodied carbon than brick and block. Indeed timber frames manufactured from trees sourced from sustainable forests provides an opportunity for storing carbon in buildings that has been removed from the atmosphere while the tree was growing. This would mean the frame of the building becomes carbon negative. The CCC further anticipates buildings to be designed better so that they need fewer materials; more materials to be reused within the construction industry; and increased use of natural and industrial-waste products to replace clinker in cement production. 

This increased efficiency of material use means that significant reductions in embodied carbon can be achieved at no net additional cost and future targets for 2030 advocated by the Royal Institute of British Architects are achievable with a cost uplift of 7 – 15% depending on building type.³² Longer term, the GHGs associated with manufacturing construction products will reduce through the decarbonisation of the energy sources these industries use and carbon capture and storage equipment fitted to the manufacturing facilities.

Whilst both the Future Homes Standard and Future Buildings Standard will reduce GHG emissions associated with the operation of new buildings, the technical standards are only notional and may be changed, or the timeline may slip.³² Local Plan reviews should implement zero-carbon buildings in operation and set embodied carbon targets as soon as possible where viable.

Making It Happen

Viability of net-zero homes

In the experience of local authorities, large-volume housing developers can argue successfully that the costs associated with building to high energy efficiency standards means that other social and environmental benefits of development, such as the provision of affordable housing for local people, has to be reduced. However, Cornwall Council has shown the additional cost of building a home to net-zero standards in comparison to those to be implemented from 2022 to be no more than 2.2%.³³ We must collectively work on demonstrating that it is financially viable to build quality, net-zero carbon homes.

First, by maintaining a county-wide evidence base about the costs of developing net-zero carbon homes to assist each planning authority in evaluating the viability of mandating net-zero standards in their area ahead of 2025. Assessments of viability need to be bespoke to each planning authority because these reports have to reflect local issues, such as land prices, housing availability and build costs. Yet there are shared issues between areas and therefore it would be beneficial to produce a shared resource. 

Second, Devon Climate Emergency partners with land assets with the potential for housing development should work with developers to move away from traditional construction approaches, which struggle to achieve the high-performance standards required for net-zero.³⁴ Instead the viability of delivering net-zero homes using modern construction techniques, such as off-site pre-fabricated timber frames, should be demonstrated. Land owners taking the lead on setting higher standards can help develop the economies of scale required to up-skill the workforce, establish supply chains, lower costs and increase the energy performance of the final build.

Urban Cooling

Vegetation, including trees, green walls and green spaces, should be incorporated into new development to help conserve energy³⁵ by providing shading and cooling of the local area through evapotranspiration.  

Setting an example 

As anchor institutions the Devon Climate Emergency partners must implement net-zero standards for their new buildings to demonstrate leadership to encourage all organisations in Devon to do the same. There is already precedent for low-carbon public buildings in Devon, such as Loddiswell Primary School, which generates more energy in a year than it consumes, Montgomery Primary School which is Europe’s first Passivhaus School,³⁶ and Exeter’s Passivhaus leisure centre.³⁷ This will encourage the supply chain to respond to the challenge and establish Devon’s as a centre of low-carbon building expertise. 

The Actions

B11. Produce a regularly-updated Devon-wide evidence base on the costs of developing net-zero carbon homes for use in Local Plan viability appraisals. 

B12. Local Plan reviews to implement zero-carbon buildings in operation and set embodied carbon targets as soon as possible where viable.

B13. Demonstrate the viability of building net-zero carbon homes using modern construction techniques by reviewing the opportunity for local authorities to use their own land in partnership with a developer.

B14. Planning authorities to ensure vegetation, and the necessary arrangements for maintenance, is included within new development to aid building energy efficiency. 

B15. Anchor institutions to deliver net-zero new build to set an example to other regional organisations and establish the South West as a leading region for low-carbon buildings.  

Case Study

Plymouth Energy Community Homes: affordable net-zero homes 

Plymouth Energy Community (PEC) Homes is building 38 net-zero new build homes in Kings Tamerton, Plymouth, supported by Homes England and in partnership with Plymouth City Council. It is the first development in a pipeline of locally owned net-zero affordable housing in the area. These will offer local people comfortable homes with low bills, due to reduced energy needs and a fair rent. 

PEC believe that delivering affordable net-zero homes requires market innovation. Their model offers community shares so that the housing will be cooperatively owned and run, just like their solar installations. PEC Homes intends to demonstrate a model that can be replicated without ongoing Government support. 

To do this, PEC Homes are using approaches to delivering net-zero housing developed by the Dutch Government in 2010, known as ‘Energiesprong’. A key element of the approach includes performance guarantees for the tenant, such as thermal comfort levels and annual net-zero energy. The long-term reduced energy and maintenance costs enable PEC Homes to finance higher initial investment costs. The approach also uses off-site manufacture of building components to achieve higher quality performance at reduced costs through economies of scale.³⁸

The streetlights in the Devon County Council area are switched off between 00:30 and 05:30 in quieter locations and in areas of high night-time activity, such as town centres, the lights remain lit but are dimmed. The authority is converting all 79,000 streetlights to LEDs by 2023; this will reduce the carbon emissions generated by its street lighting each year by 75%.³⁹ Plymouth City Council is replacing all of its streetlights with LEDs to achieve a 70% carbon saving,⁴⁰ as is Torbay Council which has already replaced 70% of its lamps with LED alternatives.⁴¹

Highways England, which manages lighting on the A38 and M5, has plans to switch 70% of its lighting to LEDs by 2027 and all of it by 2030. 

Making It Happen

Given the imperative to reduce energy demand, highways authorities must revisit opportunities to switch off street lighting. It is important that lighting is not rationalised where it would reduce take-up of active travel and must be done in consultation with local councils. 

Managers of property that has external lighting should look for opportunities to rationalise lighting provision and convert lamps to LED.  

The Actions

B16. All organisations to review external lighting provision and switch to LED technology. 

Needing action beyond Devon

B17. Work with Highways England to review opportunities for rationalisation of streetlight provision on its Devon network.