Key Points
- Croydon policy sparked infill housing boom.
- Short-lived 2019-2022 Suburban Design Guide.
- Centre for Cities research praises experiment.
- Model for other London boroughs now.
- Rules-based planning boosted small-site homes.
Croydon (Londoners News) February 12, 2026 – A short-lived policy experiment in the London Borough of Croydon has been credited with sparking a significant boom in infill housing on small sites, according to fresh research published by the think tank Centre for Cities in early 2026. The Suburban Design Guide (SDG), in place from 2019 to 2022, provided clear, rules-based guidance for developments, reducing discretionary decision-making by planners and leading to a surge in new homes. This approach is now being touted as a potential blueprint for other boroughs grappling with London’s housing crisis.
What was Croydon’s short-lived policy?
The policy in question was the Suburban Design Guide (SDG), formally adopted by Croydon Council in September 2020 following a full council meeting. As detailed in the Centre for Cities briefing ‘Croydon calling: Lessons on rules-based planning’, from 2019 to 2022, an ‘experiment’ in rules-based planning was conducted in Croydon. The borough’s ‘Suburban Design Guide’ (SDG) provided clear guidance on allowable development on small sites, making local planning more rules-based and less discretionary.
As reported by the Planning Resource team in their article “Croydon adopts suburban densification planning document” published on September 8, 2020, the document was intended to provide guidance for suburban residential developments and extensions across the borough. It targeted approximately 10,000 of the council’s 2018 local plan housing target of 32,890 new homes by 2036 to be delivered through small-scale suburban developments, known as windfall developments.
The SDG fleshed out a local plan policy identifying four “Areas of Focused Intensification”: around Kenley station; Forestdale Neighbourhood Centre; Brighton Road (Sanderstead Road) Local Centre; and settings of Shirley Local Centre and Shirley Road Neighbourhood Centre. These areas were selected for their established infrastructure, low density, and potential for significant residential increase.
How did the Suburban Design Guide work?
The SDG shifted planning from subjective case-by-case approvals to predefined rules, specifying allowable designs, heights, and scales for small sites under 0.25 hectares. According to the Centre for Cities introduction section, the positive impact of the policy has been widely reported. The Financial Times, the Greater London Authority (GLA), and previous Centre for Cities research have all noted the uptick in small-site housebuilding that occurred in Croydon while the policy was in place.
This rules-based approach minimised delays and appeals, encouraging developers to pursue infill opportunities on backlands, garage sites, and underutilised plots. Examples include the LSI Architects’ project at 196 Sydenham Road, approved in 2019, which delivered twelve homes by replacing derelict garages with mews houses and extending existing buildings.
Dean Gibson, North Area Planning Team at Croydon Council, stated: “LSI Architects scheme at 196 Sydenham Road was highly regarded by Croydon’s Planning Team and the Chair of the Planning Committee. In particular, the new mews houses in the rear of the site epitomises our ambition to optimise the potential of existing residential land through original, innovative and high quality sustainable design.”
The Croydon Small Sites Programme, linked to Brick by Brick (the council’s housing company), transformed awkward parcels into 800 homes across 24 sites by spring 2023, with another 1,000 in planning by 2020. This included community facilities and public realm improvements through standardised components for site-sensitive designs.
Why was the policy axed?
The SDG was revoked around 2022, amid shifting political priorities and external pressures. As noted in the Centre for Cities report, the experiment ended, though exact reasons like mayoral interventions or local opposition are implied in broader contexts. The Mayor of London had revoked SPD2, used for infill justifications, promoting design over density and respecting suburban character.
Critics, including Inside Croydon in their August 3, 2022, article “Oversupply of flats in borough is due to ‘profit over need’”, argued that policies under former planning chief Paul Scott, director Heather Cheesbrough, and chief executive Jo Negrini led to oversaturation with small flats, driven by profitability rather than need. Government data showed Croydon exceeding targets (4,249 homes 2018-2021), but with too many executive apartments, blighting suburbs and annexing green spaces.
The London Plan revisions increased small-site targets from 14,348 to 20,790 dwellings, but Croydon’s approach drew scrutiny for park sales and playground losses.
What impact did it have on housing delivery?
The policy triggered a boom, with small-site housebuilding surging during 2019-2022. The Architects’ Journal post on LinkedIn, dated February 10, 2026, states: A short-lived ‘experiment’ to densify housing on small sites in Croydon led to a boom in new homes.
Centre for Cities’ 2026 research quantifies this: a 700% growth in some metrics, per secondary reports, though primary data notes an “uptick” praised by FT and GLA. By 2023, 800 homes were complete, pipeline at 11,893 units as of March 2022. Annual targets rose to 2,079 until 2029, with council proposing 1,200 post-2029 to 2040.
Infill projects like Auckland Rise by Brick by Brick exemplified suburban schemes, featuring on Architects’ Journal covers. The programme, started in 2015 but boosted by SDG, used collaborative design sessions for DNA-specific developments.
Is this a model for other boroughs?
Yes, per the research. Centre for Cities briefing asks: Could this experience be replicated in other London boroughs, and in other cities? It offers hope for low-density cities, with national pushes for rules-based NPPF changes and London’s design code proposals. Secretary of State and Housing Minister advocate a ‘default yes’ for urban infill.
GLA notes Croydon’s success, while LinkedIn comments from Formwerks Architectural Inc. call it “Great example of how targeted policies can drive meaningful urban development and inspire other boroughs.”
However, challenges persist: New Barnet could rise from 26 to 32 dwellings per hectare, but resistance in Hackney shows school strains from shortages. Croydon’s Housing Strategy 2024-2029 addresses ongoing demand, reviewing allocations amid net needs of 1,028 intermediate homes yearly, prioritising 70% affordable rented.
What lessons emerge from the research?
Key unanswered questions from Centre for Cities: How did SDG achieve the increase? What ensures longevity? Sections analyse mechanics (clear rules reduced discretion), impact (quantified boom), explanations (developer confidence), and implications.
Recommendations span local, mayoral, national levels: Adopt design codes, prioritise small sites, standardise processes. Grounded Practice highlights value-for-money via components. Critics warn of oversupply pitfalls, as in Leatherhead where high-rises risk ‘another Croydon’. Campaigners push brownfield reuse.
How does this fit London’s housing context?
London faces acute shortages; Croydon’s experiment aligns with Mayor’s Plan for evolution, targeting small sites. Yet, Burwood parallels (unrelated Croydon) show density debates. 2026 research revives SDG as blueprint amid 20,790 small-site goals. Pipeline sustains delivery, but quality vs quantity debates linger.
Harp & Harp Architects noted: “We wanted homes that felt part of the community, not just stacked boxes.” In projects blending into streetscapes.
CVRA’s 2023 consultation urged removing intensification areas, 3-storey policies for character preservation. National consultations echo Croydon: rules over discretion. For cities beyond London, low-density areas could replicate via design guides. Croydon’s 2024-2029 Strategy tackles demand, maximising affordable via SHMA: high rental need over intermediate. Pipeline strong at 11,893 (2022).
