St Modwen Developments Ltd v Secretary of State for Communities and Local Government & Ors [2017] EWCA Civ 1643
St Modwen is a leading Court of Appeal authority on the former five-year housing land supply policy and, in particular, the difference between a site being deliverable and homes actually being delivered.
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- Neutral citation
- [2017] EWCA Civ 1643; [2018] PTSR 746
- Court
- Court of Appeal (Civil Division)
- Judgment date
- 20th October 2017
- Judge
- Jackson LJ, McCombe LJ and Lindblom LJ
- Case number
- C1/2016/1427
Deliverability is not the same as delivery
The Court of Appeal stressed that a site could properly be regarded as deliverable even though there was uncertainty about whether every anticipated dwelling would actually be built within the five-year period.
The policy test concerned whether sites were available, suitable, achievable and viable with a realistic prospect of housing being delivered. It did not require certainty or proof on the balance of probabilities that the projected number of homes would actually be completed.
Planning cannot control the housing market
Lord Justice Lindblom distinguished the capability of a site to deliver housing from the market’s eventual rate of delivery. Landowners and housebuilders may slow or defer development for commercial reasons beyond the planning authority’s control.
The principle is tied to the policy wording in force at the time
St Modwen interpreted the 2012 NPPF and its then definition of deliverable. National housing-supply policy has since changed, so the judgment should not be used as though the old wording still governs current five-year supply calculations. Its distinction between planning deliverability and actual market delivery remains important when reading authorities from that period.
Read the judgment
The full Court of Appeal judgment is available from BAILII: St Modwen Developments Ltd [2017] EWCA Civ 1643.
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St Modwen Case Law Page Updated: 11th September 2026