Retrofitting Listed Buildings

Author: Joyce Bullivant

There are approximately 26 million domestic properties in the UK that will have to have been retrofitted by 2050 to reach the target set for retrofitting domestic dwellings, and this is very much a moving target as older industrial and commercial properties are converted into dwellings not retrofitted at the same time, and new builds which will need to be brought up to standard. It is also important given the present housing shortages that every available older property is brought up to standard and used.

Government green grants have spectacularly failed due to lack of strategic thinking, poor publicity, and underfunding, but also because of lack of skills training both at architect level and builder level. The present cost of retrofitting at even the most basic level is on average £38’000, rising to around £69’000 for a deep level retrofit. The government grant fell well below the bottom estimate. Funding from the government has been piecemeal and poorly targeted but the biggest failures are the lack of consistency, infrastructure, and coherent conceptual design.

For any project to be successful there needs to be a clear policy lead, a long-term strategy, and a variety of income streams, including charitable, commercial, green bonds and accessible low-cost loans. It is not enough to throw money to a large contractor and hope for the best.

Mark Siddall, principal architect and director of research at the Lovely Engineered Architectural Practice (LEAP) said:

“At the moment the amount of work that has to happen - to increase the skill base, the knowledge base and the people working in that area - is not enough, so a huge scaling up process is required.”

A fifth (22%) of all residential stock in England was built before 1919. It is the least energy efficient but has the greatest potential for energy and carbon savings. Converted historic properties (pre-1919) provided 51,110 new homes between 2012 and 2018, up from 5,053,970 to 5,105,080. Changes in the High Street such as closure of banks and pubs as well as old industrial buildings becoming vacant means change of use to residential accommodation is likely to expand.

Solid wall construction buildings like Victorian terraces are difficult to treat and need more care but are also likely to be the houses in most need. Pre-1919 housing stock’s operational carbon emissions are estimated at 86 kgCO2/m2 /year (Moran et al., 2014), with average annual emissions of 9.4 tCO2e compared to 1.5 tCO2e in newer housing stock technical improvements have the potential to offer a 40% reduction in emissions, while 20% of all buildings’ carbon emissions can be addressed through insulation to increase the thermal performance (MacKenzie et al., 2010)

In terms of costs, Siddall adds: 

“It’s important to have a strategy. Have a framework in place that allows you to undertake a retrofit — you’ll need a well-thought -through design, and then be able to implement a retrofit in one go. This is the lower-cost approach, as it can help you avoid scaffolding costs several times. And of course, you’ll need to make sure you can work within your budget.”

Low cost should not be low quality and low wages to match. As seen from many failures, re- outsourcing to national or international corporations, big is not always beautiful. The drive for high profits and low costs has led to high prices, low quality work and labour shortages as wages have made building trade jobs unattractive and smaller local building companies struggle to compete. But small local builders are essential to the continued maintenance and repair of buildings and quick response to severe weather conditions more common now due to the changing climate.

Retrofitting is underfunded and expensive. Research into cheaper methods is needed. Older housing stock especially listed buildings and those in conservation areas have the added problem that in the absence of any real guidance, owners and planners do nothing, or may exert pressure to scrap conservation area status and listed status and demolish and rebuild. This would not be a solution, as the impact on the environment would only serve to worsen matters. It could take 40 years to recoup all the environmental impact caused by demolition and new build even if the new build is energy efficient.

Built heritage has an important part to play in an area’s economy, social cohesion, and mental health. It is a clear sign of importance to the population that in Sheffield there are over 250 heritage organisations (not counting those only online) many of which have been going for over thirty years and some whose membership numbers are into thousands. Caring for heritage is not restricted to Sheffield and it is calculated that the heritage sector is an important source of economic prosperity. Historic England found that between 2011 and 2016 the heritage sector contribution to Gross Value Added has increased by 37% from £21.1bn to £29bn. Nearly two thirds - 62% - of all respondents felt trading from a listed building enhanced their business, with those in the hospitality sector the most positive at 71%.

On the 20th February 2023 a motion was put forward to Sheffield council to drive forward the heritage strategy developed and promoted by Joined Up Heritage. In promoting the motion Tom Hunt, then councillor for Walkley, now leader of the Council said: “Adopting the strategy will ensure our heritage has an important place in how we plan Sheffield’s future.”

The motion was accepted and there are two relevant sections that still need to be looked at in depth. The council states that it believes:

“that the impact of heritage as a means to stimulate investment is evident in the huge success of the Kelham Island development and the redevelopment of the City Centre;

and

“… further believes adopting the Heritage Strategy for Sheffield will demonstrate the council’s strategic approach and commitment to heritage, and that having this strategic approach will greatly improve the council’s ability to attract external funding for a wide range of heritage projects.”

Heritage is indeed important for a wide variety of reasons but there would often seem to be a lack of understanding as to what heritage can do re drawing in funding into the local economy. Heritage is a funding ‘Heineken’: it can reach sources of funding that councils cannot reach.

Historic England estimates that 1 in 5 residential listed buildings are also used as a place of work There are over half a million listed buildings in England and Wales –thirty thousand in Yorkshire alone. Most are privately owned, with a high proportion used commercially.

With the rise in energy prices as well as the desire to cut carbon emissions there has been a growth of demand for retrofitting buildings but there is a serious shortfall in trained evaluators and retrofitters. When it comes to restoring and retrofitting listed buildings qualified people in the commercial sector would seem to be non-existent. There are no overall agreed standards. Heritage England said when questioned by me that there had not been enough research for them to publish guidelines. This places all historic buildings in danger of clumsy, damaging retrofitting or having protection removed. 

The historic character of an area has been found to have economic importance, especially commercially, but is often overlooked by councils keen to show a skyline of new towering buildings as proof of lots of investment. As an ex-retailer (albeit in a very small way) I was always aware that to make money you must look for the gap in the market that needs to be filled. Regarding all retrofitting, but especially retrofitting listed buildings, it is not so much a gap as a deep chasm. The potential is yet to be realised. Few people have grasped that retrofitting is not merely a repair programme but has the potential to be a billion-pound industry supplying lifetime jobs in areas where well paid permanent jobs are in short supply.

The problems regarding historic buildings do not just apply to the retrofitting of listed buildings, but a problem that covers the whole of retrofitting industry. The first problem being that it is not seen as an industry and the lack of knowledge in all aspects is holding it back. The failure to see that materials and methods used will have to be continually assessed as new technology and new materials are made available. All retrofitting will need to be monitored to ensure that it does what it says on the tin. New methods need to be devised to make retrofitting affordable as well as protect heritage buildings by finding appropriate methods.

There needs to be a centre of excellence with training to an agreed standard which includes at least a basic knowledge of building methods and structures so they can advise on the best course of action and an advisory centre for building owners to know what they can do. An independent body is essential to avoid large corporations overcharging while failing to meet standards necessary. One size does not fit all and expertise in repairs and restoration work is also needed. With so much focus on new build, repairs and home improvements being taxed, plus poor pay and conditions in the building industry, there has been a drop in restoration skills and heritage building crafts such as stone masonry and lime plastering.

A previous repair to external plaster at Bishops House in Sheffield was found to be Polyfilla and led to large cracks and some plaster falling off. A specialist had to be brought from London to oversee repairs and using lime plaster. Even so, that expert was not aware of the local phenomenon of backing the plaster with slate and initially thought it was another clumsy repair till shown a piece written on the subject by a local historian.

There should be a requirement that retrofitters have to be of a certain standard like the idea of corgi fitters re gas systems. With several million buildings to be retrofitted at the cost of billions of pounds, without such quality control it risks damage to premises and failure to cut energy use. It would damage customer and investor confidence which at present is low. For any chance of retrofitting targets to be met the retrofit must be made to last.

On present experience government funding is likely to be lower than required both per building and for necessary training and research. Individual incomes for pre-1919 properties are likely to be higher than for the average homeowner, and those using them as a business premises will be more likely to be able to borrow money to cut their running costs. The potential for green investors is substantial if the risks can be minimised by certification, ongoing research, and continual evaluation. The problem is that we need to set up an initial training and research project to present to future investors and to persuade possibly a revision on what can be done with historic buildings in conservation areas.

Listed buildings that are used by charities are open to a variety of funding that other buildings do not have. They could also prove to have potential for sponsorship by a corporation wanting to be community friendly and claim it is cutting emissions by retrofitting popular community hubs. Using funding available for restoring or maintaining a listed buildings use could also fund apprenticeships and research into all forms of retrofitting and the building used as an exemplar to those considering green investments. 

We have examples in Sheffield of substantial HLF funding that helped listed buildings become more energy efficient such as the grant to Sheffield Cathedral that allowed them to put in underfloor heating. With Sheffield diocese now having acquired funding to work towards zero carbon emissions, now would seem a good time to work collaboratively with all the charities using listed buildings to raise funding for training and research that could set up Sheffield as a centre of excellence re retrofitting. With the rise in commercial and privately owned sector retrofitting this would create more trained assessors and retrofitters, data to improve the application and cost as well as sourcing sustainable materials where possible, making it cheaper to retrofit social housing as well as make sure any funding was adequate & based on realistic costs.

But also cutting energy costs throughout will in effect raise incomes and boost the local economy. It will do the same for every area if the quality is controlled, wages kept at reasonable levels to encourage a larger workforce and the local firms, who can respond quickly to change, are used.

Historically, this would not be the first time that Sheffield has set the bar for green policies that the rest of the county later followed. Nor the first time the use of expertise in industry was used to adapt to changing circumstances and create completely new industries.

References

Woodfield Jack 2022 October 4th Retrofitting a Home: The Definitive Guide, Homebuilding and Renovating https://www.homebuilding.co.uk/advice/retrofitting

University of Nottingham, 2022 27th October Retrofitting the UK’s housing stock for carbon neutrality will require significant investment, says new study. https://www.nottingham.ac.uk

Historic England 2018 6th December New Report: Rise in Number of Businesses Occupying Listed Buildings https://historicengland.org.uk

Sarshar Marjan, 2018 26th October UK Needs to retrofit 26 million homes by 2050 to reduce greenhouse gas emissions  The Institution of Engineering and Technology (IET) https://www.politicshome

Green Finance Institute 2021 13th July, Local Climate Bonds a cost-effective way to raise billions for councils’ green plans, says new campaign  https://www.greenfinanceinstitute.co.uk

Van Halm Isabeau 2023 6th March, One-third of UK funding for heat pumps and insulation is unspent Energy Monitor Built environment https://www.energymonitor.ai/tech/built-

Fenton Josh 2021 25th March Government is failing on domestic retrofit, so what can architects do? Architects Journal https://www.architectsjournal.co.uk

Webb Sam, 2023 14th January How 'deep retrofits' could end up costing you a huge £69,000 - more than double the figure claimed by the government. https://www.homebuilding.co.uk

Gardiner Joey 2021 20th October Industry laments ‘shocking’ failure to introduce domestic programme Housing Today https://www.housingtoday.co.uk

The publisher is Citizen Network. Retrofitting Listed Buildings © Joyce Bullivant 2023.