Five year housing land supply
We are required to maintain a five-year advance supply of land for housebuilding, updated annually. These are the most recent calculations as at March 2023:
| a | Core Strategy and Urban Core Plan (CSUCP) requirement 2023-28 | 2556 |
| b | Requirement plus 2010-23 net undersupply (taking account of student housing completions) | 4514 |
| c | Requirement including undersupply, plus 5% buffer (see note 3) | 4740 |
| d | Calculated supply 2023-28 from deliverable sites | 3026 |
| e | Calculated supply plus assumed windfall (see note 1) | 3226 |
| f | Total supply as a percentage = 3226/4740 = | 68.1% |
| g | Total supply in years | 3.40 years |
Notes
(1) Before 2017, a windfall assumption (described as "conservative") of 50 dwellings per annum was included. The figure was then reduced to 25 per year, to take account of the availability of up-to-date information and the reduction in the minimum site size from 5 or more dwellings to 3 or more dwellings from the 2017 SHLAA onwards. However based on more recent experience it has now been increased to 40 dwellings p.a.
(2) In contrast to the method used in some earlier years, no explicit allowance is made for bringing empty homes back into use, as the Core Strategy and Urban Core Plan (CSUCP) requirement already takes account of an assumption about reducing the vacancy rate by doing so.
(3) Assumed 5% buffer as delivery over 2020-23 is likely to be 90-91% of the requirement, but awaits confirmation from the government's calculation for the Housing Delivery Test.
(4) The figure in row (d) represents the estimated deliverable capacity on suitable sites within the five-year period. Details of the individual sites and their estimated likely annual delivery of completions is included in the Strategic Housing Land Availability Assessment (SHLAA) (Update for March 2023) and particularly in the Trajectory included in that document as Appendix 2. The Core Strategy requirement for 2023-28 (row (a) above) is calculated by annualising the five-year net provision totals in CSUCP policy CS10.
The new definition of deliverability published by the government on 24 July 2018, the increased Core Strategy requirement for the period 2020-25, and the continuing under-delivery are the principal causes of the reduction in the calculated five-year supply since 2018.