Making historic homes more energy efficient
- Why make your home more energy efficient?
- General principles
- Quick wins
- Substantial upgrades
- What consents do I need?
The UK has committed to reaching ‘net zero carbon’, where we do not create more carbon emissions than we absorb, by 2050. National and local government have brought in high energy efficiency standards for new homes, but we cannot meet our climate targets without reducing emissions and energy usage in all our homes. Improving energy efficiency is not only good for the climate, but it will also reduce your running costs, and increase the lifespan of your building.
Nationally, about 20% of our homes were built before 1919, using traditional timber-frame or solid wall construction methods and materials. Maintaining the buildings we use is a powerful climate action as it ‘locks in’ the carbon used to build these in the first place, so if you are able, the responsible adaption of an old building is preferable to the purchase of a new building.
When a typical Victorian terraced house is sympathetically refurbished and retrofitted it will emit less carbon by 2050 than a new building built to current standards, if you take into consideration not just the energy used in the building but also the carbon ‘locked up’ in the home’s materials; construction of a new home of the same size produces up to 13 times more carbon than refurbishment.
Adaption to climate change and conservation of heritage are compatible aims. We do not need to accept the loss or deterioration of our collective heritage to achieve our climate goals. The heritage sector is founded on the concept of intergenerational equity that also underpins sustainable development – that we must not prioritise ourselves over future generations. Conservation is, by definition, the process of managed change which sustains significance.
What else are the councils doing?
Both councils have declared a Climate Emergency and are taking strong action to cut emissions in the area.
South Cambridgeshire District Council adopted an ambitious Zero Carbon Strategy in May 2020 and a Business Plan 2019-2024 which sets out high level actions on zero carbon, including that we will help cut the carbon footprint from homes (which account for around 20% of carbon emissions from the district).
Cambridge City Council declared a climate emergency in February 2019 and have set an aspiration for the city of Cambridge to achieve zero carbon status by 2050 in its Climate Change Strategy 2016-2021, which is currently being updated. A target was set to reduce the Council’s own emissions by 15-20% between 2014/15 and 2020/21 in the Carbon Management Plan 2016-2021, which was exceeded in 2018/19. The climate change strategy includes an objective to reduce energy consumption and emissions from homes by promoting energy efficiency measures, sustainable construction, renewable energy sources and behaviour change.
Buildings from different periods have fundamental differences in how they have been designed to manage heat and moisture, and the skills and materials needed to maintain, repair, and responsibly adapt them. Solutions designed for the 80% of houses built after 1919 may not be appropriate for your home. They can be aesthetically damaging, environmentally ineffective or counter-productive, and in the worst cases cause harm to the health of the occupants.
We recommend taking into account the following three compatible frameworks when considering ways to reduce the carbon footprint of a traditional or historic building:
- STBA Retrofit Principles: The Whole House Approach:
- The Whole House Approach is a way of thinking about retrofit in a manner that is holistic and risk based:
- Consider the three areas of risk: energy, health, heritage
- Take a whole building approach, accounting for: fabric, services, inhabitants’ needs and behaviour, immediate context (weather, locality), and wider context (embodied carbon, decarbonisation of fuels), integrated for a building in balance.
- Use a joined-up process (linking assessment, design, construction, feedback)
- Four aims when enhancing the sustainability of heritage assets:
- Preserve historic fabric
- Extend the beneficial use of older buildings
- Reduce carbon emissions using the hierarchical approach
- Specify environmentally conscious materials
- The Energy Hierarchy: Be Lean, Be Clean, Be Green:
- Lean: Minimise the energy demands of the building
- Clean: Use and supply energy more efficiently
- Green: Supply renewable energy
The most effective way to achieve energy efficiency is to keep buildings in good repair so that they last and do not suffer from decay requiring energy and carbon to rectify. Maintaining a building’s ability to regulate moisture levels is essential to its effective thermal performance; walls can be over a third less energy efficient if damp.
Quick wins bring big energy savings with limited investment or fabric intervention and are the often the same recommendations for both modern and traditional buildings. Quick wins can include:
- Loft insulation
- Fitting insulated curtains or shutters
- Chimney balloons
- Energy-efficient lighting
- Switching to a 100% renewable energy tariff.
Major renovation presents big opportunities and also the greatest possibility for mistakes and harm. Projects should be carefully considered using appropriate expertise, taking advantage of opportunities for enhancement and with an awareness of available technology. The following can offer significant energy savings with little negative impact on the historic significance of the building:
- Overhauling windows to ensure a snug fit can reduce air leakage by 33-50%, without loss of an important historic feature. Where a historic window is beyond repair, it may be appropriate to replace with double-glazing units as slim as 11mm - or even 6mm vacuum units - allowing for slender frames and glazing bars which maintain building appearance.
- Replacement of failing cement render with an appropriate lime render gives rise to an opportunity to add breathable insulation to external walls.
- A boiler upgrade is a highly effective method of reducing your energy usage. Renewable energy technologies, ever smaller and quieter, can often be sited in a discrete location, or effectively screened, and connected to existing pipework. They are especially welcomed where they allow for the removal of a large gas or oil tank, although will need to be combined with fabric improvements and be used in tandem with underfloor heating or oversized radiators to ensure that they work efficiently.
Planning permission and listed building consent
Getting consent is not a barrier to improving the energy efficiency of your home. Many energy efficiency measures do not require planning permission or listed building consent, but as this is a complex area, please ask us for advice.
If your home is within a Conservation Area, but is not a listed building, please consult the Planning Portal Interactive House. Alternatively, please use our free Duty Planning Service to find out if you need planning permission, by either contacting the Historic Environment Team or by using our online form to book a Duty Planning appointment. (Please note, the online form is for South Cambridgeshire only).
If your home is a listed building, please contact the Historic Environment Team, and we will help you understand the consents that are needed.
After your initial enquiry, we may recommend that you ask us for formal Pre-Application Advice, which will allow us to give more detailed consideration to your proposal, and an option to include specialist advice e.g. a Conservation Officer, or Sustainability Officer.
You can apply for planning permission or listed building consent through the Planning Portal.
Where planning permission is required, applications in South Cambridgeshire will be determined in accordance with Local Plan Policy NH/15: Heritage Assets and Adapting to Climate Change, and applications in Cambridge City will be determined in accordance with Policy 63: Works to a heritage asset to address climate change.
Building Regulations may be required for carrying out works to make your historic home more energy efficient.
The Building Regulations for conservation of fuel and power in existing dwellings (Part L1B) require special consideration for buildings of traditional construction as well as listed buildings and buildings in Conservation Areas, specifying that the aim should be to improve energy efficiency as far as is reasonably practicable. The work should not prejudice the character of the host building or increase the risk of long-term deterioration of the building fabric or fittings.
To find out whether building regulations are required for your work, please visit the 3C Building Control website for further information, or email 3C Building Control to talk through your scheme. The first hour of advice is free. Please provide as much detail as possible and your enquiry will be forwarded to a surveyor in the first instance.
Historic England: Climate Change, Sustainability & Energy Efficiency. A gateway to Historic England’s extensive advice and research, worth exploring. Particularly pages Practical Guidance on Energy Efficiency and Generating Energy in Older Houses and overarching guidance documents:
- Energy Efficiency and Historic Buildings (2018)
- HEAN14: Energy Efficiency and Traditional Homes (2020)
Planning responsible retrofit of traditional buildings (PDF) Sustainable Traditional Buildings Alliance (STBA). Part of the ‘Responsible Retrofit Series’. The STBA is a collaboration of not-for-profit organisations supported by supported by CITB, Historic England, Historic Environment Scotland, and Cadw.
Society for the Protection of Ancient Buildings (SPAB): Knowledge Base. A growing resource on conservation old buildings including categories Common Problems, Maintenance, and Energy Efficiency.
Old House Eco House: A Practical Guide to Retrofitting for Energy Efficiency and Sustainability (2019) Suhr & Hunt in association with SPAB
A Bristolian’s Guide to Solid Wall Insulation (2015) STBA, DECC, Bristol City Council. This illustrated guide is now used by homeowners throughout the UK to make more informed decisions about how to insulate their homes.
Love Your Old Home workbook (2014) Centre for Sustainable Energy (CSE), a homeowner’s guide to significance and planning energy efficiency improvements in traditional homes.
Heritage Counts Research published by Historic England on behalf of the Historic Environment Forum, particularly: There’s No Place Like Old Homes: Re-use and Recycle to Reduce Carbon (2019)
Case Studies including the Zetland Passive House ‘the UK’s greenest retrofit’ in Chorlton Conservation Area, the eco-retrofit of a Grade II listed Clapham townhouse. Slightly deviating from domestic examples but closer to home: Going Green at Wimpole, and an ‘exemplary retrofit’ at Trinity College Cambridge.
South Cambridgeshire District Council / Greater Cambridge Shared Planning
Watch our webinar on greening your older home
South Cambridgeshire Local Plan 2018, Policy NH/15: Heritage Assets and Adapting to Climate Change and supporting text, (p 21).
Greater Cambridge Sustainable Design and Construction Supplementary Planning Document 2020, 3.10: Works to heritage assets to address climate change
South Cambridgeshire Listed Buildings SPD 2009, Chapter 14, Sustainability, Energy Efficiency and Listed Buildings [Please note policy and technology references are out of date, however the principles remain relevant]
This webpage is intended to grow and evolve. If you have any feedback to aid this process, please contact the Historic Environment Team. We are currently exploring:
Case Studies of Best Practice, including examples of adaptions within Conservation Areas and Listed Buildings. If you know of any examples of energy efficiency improvements in local historic buildings that you think should be featured, no matter how big or small, please contact the Historic Environment Team with the subject ‘Case Study’.
Bookable free ‘surgery’ appointments for residents of listed buildings and conservation areas to discuss proposals to improve energy efficiency with a Conservation Officer. If you would be interested in this service please contact the Historic Environment Team with the subject ‘Surgery’.
Waiving householder pre-application and/or application fees for decarbonising proposals where permitted development rights have been removed due to being within a Conservation Area, to complement our existing removal of fees for pre-applications related to article 4 directions or removal of permitted development rights through planning conditions.