How much of England's new affordable housing meets the national standard?
What this research is about
England introduced a national space standard for new homes in 2015. Unlike some other standards, compliance is not required by building regulations — it operates through the planning system, and only where local authorities have chosen to adopt it. This research examines what that means in practice, analysing 9,876 newly built affordable housing units across 153 developments in England completed in 2021. The findings reveal a significant gap in the standard's reach, shaped by geography, dwelling type, and the changing structure of affordable housing delivery.
How space standards work in England
Space standards set minimum floor areas and room dimensions based on furniture sizes, activity zones, and circulation clearances required for typical domestic use.Mayor of London (2010) London Housing Design Guide; MHLG (1963) Design Bulletin 6: Space in the Home. The Nationally Described Space Standard (NDSS), introduced in 2015, consolidated earlier guidance. But unlike its predecessors, it is not a funding condition. Space standards in England were historically enforced through housing subsidies: the Housing Corporation used Housing Quality Indicators (HQIs) as a mandatory requirement for its 2008 to 2015 Affordable Homes Programmes. The NDSS replaced this with a planning tool, leaving adoption to individual local authorities, each of whom must demonstrate need and economic viability before including the standard in their local plan.Ferm, J. and Raco, M. (2020) Viability planning, value capture and the geographies of market-led planning reform in England. Planning Theory and Practice, 21(2), 218–235.
This shift in mechanism coincided with a structural change in how affordable housing is delivered. The number of affordable homes obtained through planning obligations imposed on private developers now exceeds the number built using direct subsidies. Affordable housing has increasingly become a by-product of speculative private development, often designed and fully specified by the time it is handed over to housing associations. Planning obligations are extensively negotiated and policy requirements can be bypassed if standard contributions are not economically viable for developers.Ferm, J. and Raco, M. (2020); Murphy, L. (2019); Sayce, S. et al. (2017); Lord, A. et al. (2022); Morrison, N. and Burgess, G. (2014). Incentivising and controlling the design of this housing is considerably harder than it was under subsidy conditions.
Who we surveyed and what we analysed
Environmental information requests were submitted to all 322 local planning authorities in England, asking whether they had adopted the NDSS and when. Of the 79% that responded, 37% had adopted the NDSS in their local plans and a further 8% in supplementary planning documents. Of those that had adopted it, 40% did so after 2020 — that is, after the planning applications for the developments in this study were submitted.28% of local authorities reported they were planning to adopt the NDSS in the near future. Of those that had not adopted it, 85% reported using no other space standard in their local plan or planning guidance. Planning applications for 153 developments — covering 9,876 affordable units owned or managed by 15 of the largest housing associations, across nine English regions — were then analysed for floor area and layout data. Market housing type plans from three volume housebuilders were also collected for comparison.
The national picture
Nationally, only 43% of new affordable housing met the NDSS. Against the older and less demanding HQI standards, 81% complied. Dwelling sizes are tightly clustered around the median for each type — 72% of one-bedroom two-person flats fall within 5% of the median gross internal area — suggesting that standard house types used by volume housebuilders, rather than space standards, are the primary determinant of what gets built.
The regional picture
The regional variation is stark. London, where space standards equivalent to the NDSS have applied to all tenures since 2011, achieves 80% compliance. The East Midlands reaches 8%; the West Midlands 13%; Yorkshire 19%. These are not marginal differences — they represent a fundamental inequality in the quality of new affordable housing across England. In local planning authorities that have adopted the NDSS, compliance reaches 69%, compared to 29% where it has not. But even where the standard is adopted, nearly a third of homes fall below it.Mean dwelling sizes for the same dwelling types varied from 6 m² to 22 m² across regions, consistently higher in London, the South East, and the South West, and lowest in the East of England, East Midlands, West Midlands, and Yorkshire.
Houses versus flats
The gap between dwelling types is as large as the gap between regions. 71% of flats meet the NDSS; only 18% of houses do. In areas where the NDSS has been adopted, flats reach 74% and houses 47%; where it has not been adopted, flats reach 68% and houses just 13%. The difference is partly structural: 95% of affordable housing in London is provided as flats, and London has had standards in place for over a decade. But it is also geometric. The NDSS was adapted from the London Housing Design Guide, which was designed for flats. In a multi-storey terraced house, living rooms and kitchens occupy the ground floor and bedrooms the first floor; these functions require different floor areas, and the standard's method of calculation — adding up minimum room sizes — does not translate cleanly to this typology.
A further pattern concerns bedrooms. In private sector three-bedroom houses, the smallest bedroom is frequently declared as a study on planning drawings, bringing it below the NDSS single-bedroom threshold and reducing the required overall floor area.The NDSS minimum single bedroom size is 7.5 m² with a minimum width of 2.15 m. Rooms declared as studies are exempt from bedroom size requirements. This practice reflects differences in expected occupancy: approximately 85% of private homes are under-occupied relative to their maximum capacity, whereas 55% of households in social rent fully occupy all their bedrooms, and 9% live in overcrowded conditions. ONS (2023). This practice is widespread and is not reliably caught by current planning processes.
The role of volume housebuilders
Comparing affordable unit types to market housing from volume housebuilders reveals a consistent pattern: volume housebuilders size their standard house types to the HQI, not the NDSS. HQI scores appeared voluntarily on planning drawings across the sample, even though the standard is no longer required — functioning as an informal industry benchmark for demonstrating usability. The HQIs set thresholds 2 to 9 square metres lower than the NDSS for comparable dwelling types. Where standard house types dominate a development, dwelling sizes cluster around these lower thresholds regardless of whether the local authority has adopted the NDSS.Affordable and market house types did not greatly differ in layout principle. However, while the number of bathrooms is kept to a minimum in affordable homes, an en-suite to the first bedroom is commonly provided in private house types. The additional bathrooms are usually provided at the cost of a smaller bedroom. Similarly, utility rooms common in private sector houses are frequently absent from affordable equivalents.
What this means for policy
The NDSS is failing to function as a national standard. Where it has been adopted it makes a measurable difference. The voluntary mechanism, combined with a viability requirement, creates a postcode lottery in affordable housing quality that consistently disadvantages households outside London and outside flats. Mandatory minimum space standards, equivalent to those that have applied in London for over a decade, would be the most direct remedy. Restoring a link between subsidy conditions and compliance, as existed before 2015, would extend this to planning-obligation affordable housing. Neither requires new evidence. The evidence already exists.