Retrofitting for Net Zero

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What does retrofitting involve?

Grosvenor’s Heritage & Carbon report points out that, at a global level, about 40 per cent of carbon comes from the build environment. Half of this comes from operational use (residential and commercial). This is “even more marked” in London, where the figure is an astonishing 78 per cent. The report observes that “roughly 80 per cent of building that exist today will do so in 2050 and so to achieve a net-zero position, it is clear that tackling existing stock is essential”.

Within its London portfolio, which contains some 500 listed buildings, Grosvenor’s work has focused on installing better insulation, replacing gas boilers with electric heat pumps, and more energy efficient lighting.

Cornwall’s ‘whole house retrofit’ scheme addresses regular housing stock and identifies 10 areas where additions or refurbishments can improve carbon performance. The £4.2 million ‘whole house retrofit’, funded partly by the government seeks to improve 83 of the worst preforming houses by

• Decommissioning chimneys
• Loft insulation
• Solar panels
• New hot water tanks
• Insulation to external walls
• Ground-floor insulation
• Ground source heating
• Temperature controls
• Double glazing
• Single-room ventilation and heat recovery

Heritage & Carbon, the report by Grosvenor states: “The ambiguity and inconsistency of planning policy and guidance regarding energy efficiency in historic buildings has left a substantial amount of England’s existing building stock vulnerable to the impending climate crisis.”

It proposes changes to chapter 14 of the NPPF that would create “a much stronger direct link” between heritage and sustainability, as well as the addition of policies seeking carbon reduction in all existing buildings, including designated heritage assets (but not scheduled ancient monuments). The report also calls on the government to promote the use of listed building heritage partnership agreements. HPAs — agreements between building owners and local authorities that allow the latter to grant blanket consent for routine alteration works to repetitively designed buildings or groups of buildings — save time and money, but despite being introduced in 2013, they remain “vastly underutilised”.

The Architects’ Journal campaign floats changes to national planning policy, too, including a “presumption in favour of refurbishment” as a subset of the existing presumption in favour of sustainable development under NPPF paragraph 11, and the scaling back of permitted development rights that allow demolition works without permission.

From al corners, there are calls for leadership from central government on retrofit. The UK Green Building Council (UKGBC) has “joined calls from across the industry, championed by the likes of the Construction Industry Council and Federation of Master Builders, to campaign for qa national retrofit strategy” to “provide much-needed business certainty following the damage of several stop-start policy cycles and deliver a long-term plan for achieving net-zero and securing associated green jobs”.

Local Efforts

“The alternative to clear central leadership is confusion and inconsistency,” says Russell Smith, founder of RetrofitWorks, a not-for-profit cooperative that connects people or grounds that want to undertake retrofit projects with expert tradespeople who can carry out the work.

“Retrofit policy differs from council area to council area, and decisions are made on a case-by-case basis. This adds more confusion for householders who already need to think about which technology is the best choice, which contractors will be able to do the work, and which government grants they may be eligible for,” he says. “Add that to the fact that budget cuts have forced many councils to charge for pre-application advice, and the result is that ‘often people just don’t go ahead’ with retrofit works that would have shrunk their carbon footprint.”

Despite these challenges, local authorities around the country are working to make retrofitting easier for residents. One example is Cornwall Council, which has undertaken a £4.2 million pilot scheme to make 83 of its poorest-performing homes warmer and greener. Its ‘whole house retrofit innovation’ scheme (WHRI) works by carrying out numerous improvement works to a property at the same time – an approach that lowers costs through economies of scale.

The whole house retrofit model has been designed to be replicable, so that it can be deployed in other communities with similar housing stock across the UK. Cornwall Council was one of three authorities that won £7.7 million of funding from the Department for Business, Energy & Industrial Strategy to pursue whole house retrofit pilot schemes in 2020, along with Nottingham City Council and Sutton Borough Council.

The UKGBC has also been working to propagate retrofit expertise among local authorities. Through its ‘Accelerator Cities’ project to “catalyse action on home retrofit”, the organisation has created a ‘retrofit playbook’ that aims to aid councils in “developing retrofit policies and initiatives, through sharing best practice and guidance”. It offers tips on designing an overarching retrofit strategy, engaging householders and landlords, financing, and developing skills and supply chains.

Central government is still lagging behind, however, even as the fast-approaching COP26 means its climate change policy is under more scrutiny than ever before. In March, its flagship retrofit scheme, the Green Homes Grant, was scrapped just six months after it was announced. The scheme, which offered grants of up to £10,000 to pay for insulation upgrades and other efficiency measures was intended to secure improvements to 600,000 homes, but only £71 million of the £1.5 billion that has been made available was spent. The government further angered campaigners by scrapping it shortly after the 2021 budget, having missed the opportunity to announce a new programme.

In August, however, business secretary Kwasi Kwarteng indicated that the government was in talks to introduce a replacement for the Green Homes Grant. Its next opportunity to do so is through the highly anticipated Heat and Building Strategy, which is expected this autumn after repeated delays.

Whether or not the government chooses to lead on retrofitting, it seems that councils, developers, and professional bodies across the country will continue working to make Britain’s homes greener, but within a policy context that does not necessarily make it the easiest or the most cost-effective path to creating buildings that are future proofed.

Matt Moody is the section editor with The Planner.