Historic England                            SBE0098

Written evidence from Historic England

 

Introduction

 

Historic England is the Government’s statutory adviser on all matters relating to the historic environment in England. We are a non-departmental public body established under the National Heritage Act 1983 and sponsored by the Department for Digital, Culture, Media and Sport (DCMS). We champion and protect England’s historic places, providing expert advice to local planning authorities, developers, owners and communities to help ensure our historic environment is properly understood, enjoyed and cared for.

 

Summary of key points

                      The most sustainable building is the one that already exists.  To meet the government’s target of being carbon neutral by 2050, we must adapt and reuse our existing buildings first, rather than demolishing and building new.  This would mean the CO emissions already embodied within existing buildings are not lost through demolition.

                      Re-using buildings saves our finite natural resources from further exploitation and is the best way of reducing the carbon impact of new space.

                      Maintenance and repair is an unrecognised energy efficiency measure – we need policies that acknowledge the value of repair and maintenance in order to meet net zero (poorly maintained buildings are less energy efficient).  Maintenance also enables reuse while repair minimises the requirement for new materials reducing carbon emissions over the long term.

                      Traditional methods and materials are essential for maintenance, repair and reuse of existing buildings but we can also learn from traditional methods which are often low carbon and use natural materials. Investing in skills in this area supports local jobs as well as improving resilience of places to climate challenges and reducing carbon.

                      We need to ensure carbon is properly countedGovernment intervention is required to address market failure and to incentivise and inform.

 

Call for Evidence questions

 

  1. To what extent have the Climate Change Committee’s (CCC) recommendations on decarbonising the structural fabric of new homes been met?

 

Although CCC recommendations refer to new construction, new homes do not necessarily equate to new buildsHistoric buildings can be converted to new homes and doing so reduces the carbon emissions associated with construction. Traditional construction materials and methods are often low in carbon and have a role in the decarbonisation of the structural fabric of new homes.

 

  1. How can materials be employed to reduce the carbon impact of new buildings, including efficient heating and cooling, and which materials are most effective at reducing embodied carbon?

 

Making the most of the buildings we already have through maintenance, repair and reuse can greatly reduce the carbon footprint of construction – new homes and business premises don’t necessarily mean new buildings. For example, 13% of England’s net housing supply in 2019/20 was from existing buildings (conversions and change of use)[1]. This figure could be significantly increased if we were to take a re-use first approach to providing new spaces. These comments therefore refer to ‘new spaces’ as well as new buildings.

The choice of building materials and building systems has a significant impact on the lifetime emissions from new spaces and buildings. Historic England is developing deeper understanding of the embodied carbon of building materials suitable for different types of historic buildings[2]:

                      Traditional construction knowledge has significant potential to guide better modern methods of construction (MMC) for example by understanding thermal comfort and traditional passive techniques to achieve this[3] as well as the use and limitations of traditional (often nature-based) materials.  Unlike modern buildings, which rely on impermeable barriers to control air and moisture, traditional forms of building construction take up moisture from their surroundings and release it according to ambient conditions.  They heat up and cool down more slowly, making them excellent insulators throughout seasonal changes. This ability to ‘buffer’ moisture and heat can help to even out fluctuations in humidity and temperature.  This will be increasingly important for future climates[4].

 

                      Recycled building materials produce significantly less embodied carbon than new materials. Every time we extract new raw materials, manufacture and then transport building products we produce vast amounts of, often un-accounted, carbon[5].

 

                      In general, building components from natural materials produce less carbon. For example, it is estimated that an aluminium window produces 486 kgCO2 per window compared to a hardwood window, which is in fact a carbon store, estimated to sequester -125 kgCO2 per window[6].  

 

Historic England’s research shows that there is currently limited, trusted information on the embodied carbon of building materials in the UK[7]. While industry is leading the way (e.g. CIBSE 2020[8]) these activities are not enough.  Environmental Product Declarations (EPDs)[9] is an international standard that a manufacturer uses to measure and reduce the environmental impact of its products and services. Yet very few manufacturers offer EPDs[10]. Government should pursue an ambitious programme of high quality, well labelled, regulated Environmental Product Declarations (many European countries are currently pursuing this approach). EPDs would not only help consumers identify lower carbon products, it would also support producers of low carbon products and signal Government’s intentions to significantly reduce carbon emissions.

  1. What role can nature-based materials play in achieving the Government’s net zero ambition?

 

Nature-based materials produce lower levels of embodied carbon emissions. The CINARK tool[11] estimates the embodied carbon of construction materials based on Environmental Product Declarations (EPDs) data and demonstrates that natural materials produce less embodied carbon. In fact, as they also sequester carbon, they can greatly reduce overall carbon footprint.

 

Timber is a carbon store and is durable, repairable, reusable and recyclable. Timber features such as windows and doors are more easily repairable and recyclable than many oil-derived alternative products (e.g. uPVC). Reusing and recycling building components as well as investing in repair and maintenance will reduce carbon emissions.

 

Buildings of traditional construction are generally built using locally sourced natural materials and they are capable of lasting indefinitely with moderate amounts of regular maintenance. These buildings reflect the local traditions and natural resources of an area, using local materials such as plants/timber, stone, earth and brick. The skills required to produce, process, and use these materials can support not only local businesses, be compatible with biodiversity benefits but also support the resilience of communities to future climate challengesTraditional natural materials are demonstrably more resilient to climate risks such as flooding and overheating[12]. Building conservation and this traditional knowledge can be part of an innovative future for construction.

 

Reuse of older buildings can support greater use of nature-based materials to provide low carbon homes. Traditionally constructed historic buildings rely on nature-based materials for their maintenance, repair and reuse – supporting the skills needed for future use of nature-based materials for construction.

 

To achieve gains from nature-base materials we need to:

 

  1. What role can the planning system, permitted development and building regulations play in delivering a sustainable built environment? How can these policies incentivise developers to use low carbon materials and sustainable design?

 

The planning system has a critical role to play in the delivery of a sustainable built environment and from Historic England’s perspective this can be done best by encouraging the refurbishment and reuse of buildings and building materials.  To ensure there is appropriate oversight and management of retrofit options to avoid maladaptation, we need an effective planning system that allows historic character and retrofit considerations to be appropriately balanced.

 

Sustainable planning policies should support a re-use first approach to the built environment. The most sustainable way of delivering new homes, community spaces and workspaces is by adapting and reusing buildings. Re-use avoids carbon emissions and reduces pressures on our precious, finite natural resources[13]. 

 

We need to understand the implications of permitted development rights that allow for demolition of vacant and redundant, free-standing Class ZA buildings.  We are concerned this could lead to unsustainable practices. Research undertaken by Historic England demonstrates that the embodied carbon emissions from demolition and new build are very significant – up to a third of the carbon emitted by a new building over 60 years is embodied – these are emitted even before the building comes into use[14]. Evidence from RIBA shows that as much as 76% of the whole life carbon of a commercial building is embodied carbon[15]. To achieve a sustainable built environment, rather than incentivise demolition and new build we must urgently shift to incentivising refurbishment and repurposing buildings first.

 

Policies for a sustainable built environment must also consider social impacts and empower the voice of local communities. Traditional buildings have demonstrated positive social impacts promoting a local identity, local sense of place and social cohesion[16].

 

  1. What methods account for embodied carbon in buildings and how can this be consistently applied across the sector?

 

A life cycle assessment (LCA) model is currently the best method we have to take into account the whole life carbon of buildings -i.e. a method that considers the operational carbon emissions from buildings as well as the embodied carbon emissions from buildings. LCA is applicable over the entire construction sector including retrofit of historic buildings[17].

 

However, LCA is currently underutilised due to significant information and data constraints in terms of the embodied carbon of building materials and components.  To address this information gap, many countries are investing in and implementing Environment Product Declarations (EPDs). EPDs of building materials contain LCA calculations in accordance with EN 15804. The recent “TM65: Embodied carbon in building services: A calculation methodology by CIBSE (the Chartered Institute of Building Services Engineers in the UK) has detailed examples from international cases using EPDs[18]. The UK lags behind in the adoption of EPDs.

 

Historic England commissioned research to identify suitable methods for assessing the life cycle carbon emissions of different historic buildings, in the context of retrofit and demolish-and-replace[19]. The embodied and sequestered carbon of existing historic buildings is difficult to estimate, but our commissioned research[20] shows that retrofitting England’s existing 4.4 million pre-1919 domestic homes, instead of replacing them with new builds, would result in an estimated net reduction of 59.6 million tCO of embodied carbon.

 

However, existing regulations only consider operational emissions – this significantly disadvantages the carbon assessment of historic buildings. Omitting embodied emissions from the analysis of a new build results in the underestimation of the buildings total emissions by nearly 30%[21]. LCA methodology should include the emissions associated with the building’s construction, operation, maintenance/refurbishment and demolition and/or reuse.

The length of the reference study period is important in properly accounting for the impacts of embodied carbon; using a 60-year timeframe, aligning with standard building design practice, gives a consistent method for evidencing the emission benefits of building refurbishment without unfairly disadvantaging existing buildings. The evidence of lifespan is often absent from refurbishment calculations.

 

For effective sustainable decisions to be made during the concept-design phase of retrofitting historic buildings, all materials should have standardised EPDs that are designed for the same functionality and use.  Importantly, the methods for calculating CO₂ shouldnt focus exclusively on modern materials produced commercially and at scale – conducting LCAs can be prohibitively expensive, therefore support should be made available for small-scale, traditional and local manufacturers.

 

  1. Should the embodied carbon impact of alternative building materials take into account the carbon cost of manufacture and delivery to site, enabling customers to assess the relative impact of imported versus domestically sourced materials?

 

Yes. There is already a precedent set in the UK for including the carbon emissions of manufacture and delivery in the carbon cost, specifically in relation to the renewable transport fuel sector. As part of the reporting structure[22], suppliers must demonstrate compliance with set GHG requirements, which include the carbon intensity of producing and supplying the commodity. Their framework ensures that all carbon emissions are correctly accounted for while also ensuring that local producers aren’t disadvantaged.

 

It is vital that the carbon impact of the entire supply chain is properly accounted for in the building sector.  The embodied carbon of building materials, such as those that help improve energy efficiency, represent a significant proportion of a building’s whole life emissions. Our commissioned research shows that it can take decades for the embodied carbon debt to be repaid through the savings of improved energy efficiency measures[23]. Using materials that require energy intense manufacturing processes or that have been transported over large distances will increase the embodied carbon of the building which, consequently, increases the time it takes for any improved energy efficiency measures to start having a net positive impact on reducing emissions. By ignoring the manufacture and delivery of building materials, a significant proportion of a building’s emissions, across its lifetime, are being disregarded, disadvantaging the building materials which have genuinely less embodied carbon.

 

  1.                 How well is green infrastructure being incorporated into building design and developments to achieve climate resilience and other benefits?

 

Developments on national GI policy are welcome, however, we need to accelerate action, support local green spaces strategies and embed GI thinking that recognises the value of existing green spaces including their cultural, as well as natural, heritage.  With over 1,600 identified as of national historic significance, historic parks and gardens provide the major green infrastructure features for our urban places. If well-maintained, their benefits include carbon sequestration, climate adaptation, health and wellbeing[24] [25]. Despite CCC’s recommendation to counter the decline of urban green space in 2015[26], many local public park/ green spaces remain vulnerable.  While there have been innovative approaches to funding and management of public parks/green spaces there is an underlying need to recognise these sites are critical infrastructure through statute, and Government policy and financing.

 

  1.                 How should we take into account the use of materials to minimise carbon footprint, such as use of water harvesting from the roof, grey water circulation, porous surfaces for hardstanding, energy generation systems such as solar panels?

 

Learning from the past gives us a wealth of overlooked knowledge in traditional materials and practices that are low in GHG emissions, less harmful to the natural and social environment, permeable/porous by nature, and resource efficient in practice (i.e. through sustainable land use and water management practices).

 

  1. How should re-use and refurbishment of buildings be balanced with new developments?

 

Our current strategies for buildings need urgent reform because buildings are not on track to meet net zero carbon targets. We must reuse our existing buildings first, before we build new. Demolishing buildings not only produces millions of tonnes of waste (three fifths of all waste produced in the UK every year comes from construction, demolition and excavation) but building new has high energy costs and guzzles resources[27].

 

We can avoid tonnes of carbon if we re-use first. The embodied and sequestered carbon of existing historic buildings is difficult to estimate, however modelled data from commissioned research demonstrates that retrofitting 4.4 million traditional homes in England instead of replacing them with new builds, could result in an estimated net reduction of 59.6 million tCO of embodied carbon[28].

 

Prioritising refurbishment and retrofit over new build is the most sustainable practice which will generate environmental, economic and social benefits:

 

10.  What can the Government do to incentivise more repair, maintenance and retrofit of existing buildings?

 

The most critical action would be to:

 

Support re-use buildings first policies.

 

Treat repair and maintenance works as an energy efficiency measure.

 

Invest in construction sector skills for traditional materials and in retrofit skills for traditional buildings.  It is also essential for Government to recognise the need to support the skills and knowledge gap in understanding how buildings perform, the impact of maladaptation, and how to efficiently and effectively maintain and repair existing buildings. The Skills gap concern highlighted in the Climate Change Committees UK Housing Fit For the Future report (p.9) must acknowledge the importance and support needed for traditional skills as part of the low-carbon skills gap[36]. Traditional skills include understanding how to maintain, repair and retrofit the existing historic building stock, with 38% of the UKs homes dating from before 1946[37]. We would like to see the scope of the skills gap widened to include the need for traditional skills, which are a vital part of the Green Recovery.

 

Reduce VAT on repair and maintenance and remove the perverse incentives to demolish.  The current VAT rates, at 20% for refurbishment and 0% for new build, financially incentivise developers to completely demolish existing buildings and build new. These VAT rules also make it difficult and more expensive for homeowners to sympathetically adapt their older buildings to make them more efficient. Since the vast majority of our built heritage is cared for by private owners, a reduction in the VAT rate would help to incentivise best practice in repair and maintenance. Finance and funding of green initiatives must recognise that VAT exceptions or reduced VAT rates for repair and maintenance of the built historic environment will motivate the refurbishment of buildings rather than the demolition of existing ones to construct new. This helps to reduce the carbon footprint, which contributes to the preservation of the environment. At the same time, it contributes to economic prosperity.

 

A recent Ipsos MORI poll has shown that 56% of respondents supported repair and maintenance compared to new build, more than three times the 16% tending towards the opposite view[38].  Reducing VAT from 20% to 5% on home improvement works would unleash investment in housing, stimulate the economy and enable the UK’s transition to net zero carbon. According to the Federation of Master Builders, a VAT cut on home improvements could generate £15billion in new taxes, create 95,000 jobs and unlock a £1billion green revolution[39].  The Experian research report shows that reducing the VAT rate to 5% on all housing renovation and repair work between 2015 and 2020 would have had significant impact[40] including a total stimulus effect of more than £15.1billion in the UK economy as a whole.

 

Other fiscal actions should include providing grants specifically for energy efficient refurbishments, subsidising retrofit particularly of historic buildings and developing innovative finance for heritage. Investment designed to increase knowledge and skills across the construction industry in energy efficient refurbishments will also pay significant dividends.

 

Historic England has overarching guidance set out in its publications[41], such as Energy Efficiency and Historic Buildings: How to Improve Energy Efficiency and Energy Efficiency and Traditional Homes which supports and guides anyone wishing to improve energy efficiency in an historic building.  Government could also improve information and coordination by investing in embodied carbon research, signposting for low carbon products and securing a better understanding of energy efficiency measures applied to heritage.  There are currently significant information gaps about how effective new retrofit products are when applied to traditional assets. Given the scale of our historic environment (the UK has the oldest building stock in Europe[42]) and the potential risks of maladaptation, bespoke evidence, standards and metrics are needed for heritage.

 

 

May 2021

 

 

 


[1] MHCLG, Table 120, Components of net housing supply, England 2006-07 to 2019-20 https://www.gov.uk/government/statistical-data-sets/live-tables-on-net-supply-of-housing

[2] https://historicengland.org.uk/content/docs/research/understanding-carbon-in-historic-environment/

[3] Pender and Lemieux 2020  https://www.mdpi.com/2073-4433/11/6/620

[4] https://historicengland.org.uk/images-books/publications/energy-efficiency-and-traditional-homes-advice-note-14/heag295-energy-efficiency-traditional-homes/

[5] Carrig Conservation International, (2019) Understanding Carbon in the Historic Environment https://historicengland.org.uk/research/heritage-counts/2019-carbon-in-built-environment/carbon-in-built-historic-environment/

[6] Sinha and Kutnar (2012) Carbon Footprint versus Performance of Aluminium, Plastic, and Wood Window Frames from Cradle to Gate https://www.researchgate.net/publication/260798855_Carbon_Footprint_versus_Performance_of_Aluminum_Plastic_and_Wood_Window_Frames_from_Cradle_to_Gate

[7] Heritage Counts, 2021, Know your home, know your carbon. https://historicengland.org.uk/content/heritage-counts/pub/2020/hc2020-know-your-home-know-your-carbon/

[8] CIBSE (2020) Heart of the matter – calculating embodied carbon using TM65 https://www.cibsejournal.com/technical/heart-of-the-mattercalculating-embodied-energy-using-tm65/

[9] https://www.greenbooklive.com/search/scheme.jsp?id=260

[10] CIBSE (2020) Heart of the matter – calculating embodied carbon using TM65 https://www.cibsejournal.com/technical/heart-of-the-mattercalculating-embodied-energy-using-tm65/

[11] https://www.materialepyramiden.dk/

[12] https://research.historicengland.org.uk/Report.aspx?i=16097&ru=%2fResults.aspx%3fp%3d1%26n%3d10%26t%3dflooding%26ns%3d1

[13] Heritage Counts, 2021, Know your home, know your carbon. https://historicengland.org.uk/content/heritage-counts/pub/2020/hc2020-know-your-home-know-your-carbon/

[14] Carrig Conservation International, (2019) Understanding Carbon in the Historic Environment https://historicengland.org.uk/research/heritage-counts/2019-carbon-in-built-environment/carbon-in-built-historic-environment/

[15] https://www.architecture.com/-/media/GatherContent/Whole-life-carbon-assessment-for-architects/Additional-Documents/11241WholeLifeCarbonGuidancev7pdf.pdf

[16] Heritage Counts, 2020, Heritage and Society, https://historicengland.org.uk/research/heritage-counts/heritage-and-society/

[17] Carrig Conservation International, (2019) Understanding Carbon in the Historic Environment https://historicengland.org.uk/research/heritage-counts/2019-carbon-in-built-environment/carbon-in-built-historic-environment/

[18] CIBSE (2020) Heart of the matter – calculating embodied carbon using TM65 https://www.cibsejournal.com/technical/heart-of-the-mattercalculating-embodied-energy-using-tm65

[19] https://historicengland.org.uk/content/docs/research/understanding-carbon-in-historic-environment/

[20] https://historicengland.org.uk/content/docs/research/understanding-carbon-historic-environment-case-study-extension/ 

[21] Carrig Conservation International, (2019) Understanding Carbon in the Historic Environment https://historicengland.org.uk/research/heritage-counts/2019-carbon-in-built-environment/carbon-in-built-historic-environment/

[22] https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/947710/rtfo-guidance-part-2-carbon-and-sustainability-2021.pdf

[23] https://historicengland.org.uk/content/docs/research/understanding-carbon-in-historic-environment/

[24] https://historicengland.org.uk/listing/what-is-designation/registered-parks-and-gardens/

[25] https://www.forestresearch.gov.uk/documents/2515/urgp_benefits_of_green_infrastructure.pdf

[26] See report for green space benefits including urban heat island reduction https://www.theccc.org.uk/wp-content/uploads/2019/07/Outcomes-Green-infrastructure-case-study.pdf

[27] Heritage Counts 2019, https://historicengland.org.uk/research/heritage-counts/2019-carbon-in-built-environment/carbon-in-built-historic-environment/

[28] Historic England estimates based on data from University of West of England (2020) Carbon reduction scenarios in the built historic environment: Final Report. https://historicengland.org.uk/content/docs/research/carbon-reduction-scenarios-built-historic-environment/ and Carrig Conservation International, (2019) Understanding Carbon in the Historic Environment https://historicengland.org.uk/research/heritage-counts/2019-carbon-in-built-environment/carbon-in-built-historic-environment/

[29] https://historicengland.org.uk/content/heritage-counts/pub/2020/heritage-and-the-economy-2020 and https://www.sciencedirect.com/science/article/pii/S0921344919304136

[30] Dorpalen, B. Valuing carbon in pre-1919 residential buildings https://historicengland.org.uk/content/docs/research/valuing-carbon-pre-1919-residential-buildings/#:~:text=Valuing%20carbon%20in%20pre%2D1919%20residential%20buildings1&text=The%20UK%20has%20made%20a,the%20carbon%20emission%20rate4.

[31] https://www.buildingsandcities.org/insights/commentaries/retrofit-buildings-recovery.html

[32] https://www.gov.uk/government/speeches/building-a-greener-more-resilient-global-economy

[33] Anarchitecture (2017). Derby PSiCA, The benefits of heritage-led regeneration. [PDF] https://historicengland.org.uk/content/docs/local/derby-psica-legacy-report-pdf/

[34] Venerandi, A., Quattrone, G., & Capra, L. (2016). City form and well-being: what makes London neighbourhoods good places to live? In Proceedings of the 24th ACM SIGSPATIAL international conference on advances in geographic information systems (pp. 1-4). https://eprints.mdx.ac.uk/24522/1/sigspatial16.pdf

[35] DCMS, 2019. Ad-hoc statistical analysis: 2019/20 Quarter 1 Things that make adults (aged 16+) most proud of Britain, 2017/18, England, Taking Part survey www.gov.uk/government/statistical-data-sets/adhoc-statistical-analysis-201920-quarter-1

[36] https://www.theccc.org.uk/publication/uk-housing-fit-for-the-future/

[37] https://www.bre.co.uk/filelibrary/Briefing%20papers/92993_BRE_Poor-Housing_in_-Europe.pdf

[38] https://www.ipsos.com/ipsos-mori/en-uk/public-unsure-project-speed-infrastructure-if-it-means-they-have-no-voice

[39] https://www.semanticscholar.org/paper/Tax-incentives-for-cultural-heritage-conservation-Revelli/8fd911bfc7cd4472eb19e26ac805628496c66d6d?p2df and https://www.fmb.org.uk/resource/cut-the-vat-to-unleash-green-housing-revolution-party-leaders-urged.html

[40] https://www.ihbc.org.uk/resources/VAT-research-FINAL.pdf

[41] https://historicengland.org.uk/advice/technical-advice/energy-efficiency-and-historic-buildings/

[42] European Commission, 2018. Special Eurobarometer – Cultural Heritage. https://ec.europa.eu/commfrontoffice/publicopinion/index.cfm/ResultDoc/download/DocumentKy/80882