NLA’s Retrofit & Conservation Expert Panel chair and BGY Director Andrew Henriques reflect on the panel’s latest meeting, where they discussed retrofit challenges in London.

The first of three NLA Retrofit and Conservation Expert Panel meetings opened with an overarching question:

 

Session 1 was spent discussing themes around the barriers and challenges to retrofit projects, with the focus being on planning reforms, sustainability targets, heritage constraints, changes to regulatory codes, high construction costs and strain on viability. All of which have seemingly aligned perfectly in recent months to suppress development.

 

Planning reform discussions revolved around two principal issues: 1) inconsistencies between boroughs regarding retrofit policy and 2) the need to speed up the pre-planning process by reducing red tape.

 

The release of the City of London’s latest SPD (Feb/25) and Westminster City’s retrofit policy (currently in draft) were referenced as positive steps that support and promote a retrofit-first approach. However, the latest NPPF (12/2024) makes no reference to retrofit, and the Mayor’s London Growth Plan is similarly light on the sector, leading to reservations on whether the government truly understands the importance of retrofit for economic growth.

 

Suggestions around permitted development for retrofit and whether relatively non-controversial elements could bypass the formalities of planning under PD were discussed. A recent Westminster case study was referenced where a consistent approach to fabric improvements to glazing, doors and some servicing was used as a benchmark across several projects on the clients’ estate, thereby negating the need for separate applications for each project. A pragmatic approach that potentially could deliver planning efficiencies but only where there is control over several properties – perhaps applicable for the great London estates.

 

Sustainability and heritage came next on the agenda, where the discussion turned towards the sometimes-inflexible nature of heritage stakeholders to embrace the changes required for retrofit projects to deliver on sustainability and energy objectives. With no firm conclusions reached, how London can balance the need for growth against the drivers that underlie conservation is an area the panel will need to revisit in greater depth in the coming sessions.

 

The panel then pivoted to discuss escalating development costs, in part fuelled by macroeconomic factors leading to high inflation and subdued market confidence. Retrofit inherently carries greater risk than new-build construction because of uncertainty. The unpredictability of retrofits leads to high build costs that factor in unknown change. Mitigating these risks typically involves early on-site investigations, which can be particularly difficult to evaluate with occupied buildings. Residential retrofitting was raised as especially challenging owing to varying ownership structures and responsibilities, the vast range of housing construction types and people's own personal financial circumstances.

 

The need for incentives for both commercial and domestic sectors was debated. Domestic green grants for home improvements are already in practice. However, a significant boost would be to relinquish VAT on domestic retrofits (as new dwellings currently benefit). This could provide a significant financial motivation for domestic retrofit.

 

Lastly, the discussion shifted to addressing the government’s commitment to economic growth and that ‘upgrading’ London's existing buildings can emerge as not just an environmental necessity but a powerful economic catalyst. Benefits which can be summarised as follows.

 

·       Job Creation & Skills Development. Retrofitting London’s buildings creates jobs and develops specialised skills in energy efficiency and construction techniques, addressing unemployment and skills gaps.

·       Supply Chain Stimulation. Large-scale retrofitting boosts demand for insulation, HVAC systems, and smart building technologies, creating multiplier effects throughout the supply chain economy.

·       Property Value Enhancement. Energy-efficient buildings command premium values: commercial properties achieve 5-10% higher rental values, while residential properties gain 3-5% in value on average.

·       Energy Security & Cost Savings. Retrofits reduce energy consumption by 30-50%, decreasing vulnerability to price volatility and generating substantial operational savings.

· Climate Resilience. Buildings upgraded against flooding, overheating, and storms minimise business disruption costs and insurance premiums, providing economic insurance.

·       Innovation Catalyst. Retrofit challenges drive innovation in materials and technologies, creating intellectual property and export opportunities while advancing the circular economy.

·       Productivity Benefits. Improved indoor environments enhance cognitive function and reduce absenteeism, delivering significant economic value to London's knowledge economy.

In the same week when the UK’s property industry leaders and global investors descended on Cannes for a rather drizzly MIPIM 2025, and with London’s Mayor Sadiq Khan’s cameo visit, banging the drum seeking new investment for the capital, it seems obvious that the repurposing of London's building stock is not merely an environmental obligation but a strategic economic opportunity.

By embracing comprehensive retrofit programmes, London can simultaneously address climate goals, enhance energy security, create jobs, stimulate innovation, deliver homes and workplaces and drive sustainable economic growth for decades to come.