Tenure, funding scheme and spatial diffusion of residential retrofit across Great Britain

Peer-reviewed paper 7-043-26

Accelerating residential retrofit is central to net-zero targets, yet uptake remains uneven across places, tenures, and delivery funding scheme type. While a growing literature documents spatial diffusion of visible low-carbon technologies, little is known about how diffusion processes differ between owner-occupied, private, and social rental housing, or how these tenure channels interact across space.

This paper presents a large-scale spatial analysis of residential retrofit diffusion across local authorities (LAs) in England, Wales, and Scotland, distinguishing between market-led incentive schemes, namely the Feed-in Tariff (FiT), Renewable Heat Incentive (RHI), and Green Deal, and the supplier-obligation delivery scheme, Energy Company Obligation (ECO), as well as between owner/private and social housing tenure. Using longitudinal Energy Performance Certificate (EPC) records from 2012–2024, we infer retrofit events for solar photovoltaics (PV), wall insulation (WI), and heat pumps (HP), and attribute them to funding scheme type and housing tenure. Events are aggregated to LAs and analysed using global Moran’s I statistics and dynamic two-way fixed-effects panel models to identify direct and indirect (spillover) effects.

Results show that diffusion mechanisms are scheme-tenure-technology specific. PV adoption under market incentive schemes exhibits strong spatial clustering and dynamic spillovers concentrated in owner-occupied and private-rented housing. WI shows weaker but still detectable within-tenure diffusion, particularly under supplier-obligation scheme, whereas HP adoption exhibits little evidence of positive spatial spillovers. Cross-tenure effects are asymmetric and technology-specific: for PV under market incentives, owner/private adoption stimulates neighbouring social-sector uptake, while social housing delivery is negatively associated with neighbouring owner/private uptake. These findings suggest that policy design shapes not only who adopts, but also how adoption spreads spatially across mixed-tenure areas.