The Great British Retrofit: Challenges to retrofitting older properties

Meeting carbon emissions targets will require most buildings to undergo a retrofit, but retrofitting older properties presents a variety of challenges. Joe Martin, BCIS, explores

From the transformation of 19th-century cotton mills into new homes to retrofitting older properties into modern offices, there are many retrofit success stories across the UK.

It’s not surprising to see this trend emerge. Aside from preserving buildings steeped in British history, it will usually be cheaper in capital cost to refurbish rather than rebuild.

A recent BCIS study suggests that historically the amount spent on rehabilitation or conversion schemes is about 60% of newbuild for buildings of the same type.

Table showing results of recent BCIS study on rehabilitation or conversion schemes

* including Clinics and Group practice surgeries

Then there is the necessity to retrofit to reduce carbon emissions, which was put forward in the recent introduction of the London Plan Guidance (LPG).

This requires developers to conduct Whole Life Carbon assessments in their applications, encouraging developers ‘to look at refurbishing existing buildings rather than demolishing them.’

This could usher in policies that favour retrofit over new build across the rest of the country.

And as the government continues to put targets in place to reduce energy consumption from buildings and industry, upgrading or replacing existing buildings to improve energy efficiency – and reduce carbon emissions – will become a requirement not an option.

Retrofitting older properties presents a variety of challenges

The UK is cherished the world over for its historical, and often beautiful, buildings – from its Tudor timber framed buildings to elegant Georgian and Victorian terraces and 1930s houses.

Almost 38% of homes in the UK were built prior to 1946, and as much as they’re often glorified for their beauty and elegance, they’re also notorious for being draughty and energy inefficient.

The problems are similar for non-domestic buildings.

Back in 2019, it looked as though a solution could be in sight when the government pledged a £10 million innovation fund to support innovative methods to retrofit old housing to improve energy efficiency and decrease costs.

But this did not lead to any breakthrough technologies.

In the majority of cases, it’s not straightforward to improve insulation and air tightness of the external envelope, install more efficient heating such as heat pumps or introduce energy generation from solar panels.

New buildings are designed to be energy and cost-efficient

A report from the Home Builders Federation ‘Greener, Cheaper, Cleaner’ showed that ‘the average new build home emits 2.38 tonnes less of carbon each year, around one-third of the carbon produced by the average older property.’

It also showed that homeowners of new build houses and flats are saving an average of £435 a year on energy bills.

Increasingly, the energy efficiency of homes is a top priority for almost two-thirds of homebuyers – not surprising given the continued strain that the cost-of-living crisis is placing on many families and households.

However, will the greenhouse gases, produced by the demolition and embodied in the construction of a new structure, be offset by the reduction of emissions from energy used over the lifetime of the building?

This will vary from building to building, but the industry needs to get better at doing these calculations.

A shortage of skilled technicians and disruption to the supply chain

A 2022 report by the National Endowment for Science, Technology and the Arts (Nesta) – How to scale a highly skilled pump industry – found that there were only 3000 trained heat pump engineers in Britain.

However, at least 27,000 are needed over the next six years, if the government is to fulfil its target of 600,000 installations per year, by 2028.

And according to research from Architects Journal the next generation of architects and designers are not being educated in how to reuse existing buildings.

Its report found that one in eight are being taught nothing about retrofit, with 26% saying there needs to be extra focus on the topic.

A raft of encouraging measures were revealed in the Spring Budget to attract and retain more labour in construction – most notably the list of construction roles added to the Shortage Occupation List.

However, it’s unlikely that these will address the significant gap in skilled labour for specialist skills needed, either in the short or long-term.

There needs to be more commitment to, and investment in, apprenticeships that focus on developing these skills – as well as training in ongoing repair and maintenance methods, to ensure the products stay as energy efficient as possible.

And even with enough labour, there’s still the possibility that challenges within the supply chain may also provide a barrier to the achievement of the targets.

The government lacks a strategy to achieve retrofit targets

In November 2023, chancellor Jeremy Hunt announced the formation of a new Energy Efficiency Taskforce, to support the reduction of energy consumption from buildings and industry by 15%, by 2030.

More recently, the government also pledged to require all commercial non-domestic buildings achieve an EPC (Energy Performance Certificate) B rating of B by 2030.

But the Spring Budget was criticised by several green campaigners and industry bodies for its omission of any definitive national retrofit strategy to reduce the energy demand of our homes or buildings.

It was also criticised for ‘missing an opportunity’ to support retrofit through tax incentives and remove financial barriers.

However, the government has taken some of this criticism onboard.

Within a week of the Spring Budget, the government announced that £1.8bn in funding will be allocated, from April onwards, to local authorities, social housing providers and charities, to improve energy efficiency in their buildings.

It remains to be seen if we have the resources to take up these funds.

Retrofitting older properties provides environmental and societal benefits

Improvements in energy efficiency can reduce energy bills and operational carbon emissions, helping more people affected by fuel poverty, while better insulation can also improve the health of inhabitants.

A nationwide strategy needs to be implemented with enough support, investment and skilled labour in place, to deliver the high level of upgrades needed across domestic and non-domestic buildings.

The government needs to ensure that funds from its Heat Pump Ready programme and Boiler Upgrade Scheme will be invested in the right areas, to make carbon technology in homes and businesses more cost-effective and accessible.

Aside from reducing carbon emissions, it’s also increasingly important for families stuck in fuel poverty, in the wake of the cost-of-living crisis.

We also need the skills and commitment to assess each building or project individually, to make better, informed decisions regarding cost and carbon calculations.

Taking a life cycle cost approach probably favours rebuilding, while life cycle carbon calculations may come down in favour of refurbishing existing buildings.

Joe Martin

Lead consultant

BCIS