Notes and definitions for stock data

For definition of a dwelling, type of dwelling, tenure and general definition of a household see Definition of general housing terms .

Estimates of the total dwelling stock, stock changes and the tenure distribution for each country are made by Communities and Local Government, the Scottish Executive, the National Assembly for Wales, and NI Department for Social Development. These are primarily based on data for the number of dwellings (or households converted to dwellings) from the Censuses of Population. Estimates for England have been updated based on the 2001 Census.

In all English stock figures, vacant dwellings and second homes are included.

From April 1997 onwards, the method used to calculate stock includes the net gain for non-permanent dwellings, but before this date non-permanent dwellings are generally excluded from the stock figures. The number involved is insignificant but since non-permanent dwellings do play a role in meeting housing demand, an attempt has been made to include them in the stock estimates over the last decade.

Stock calculation for England

Estimates are 'Census based' for those years in which a Census was undertaken. In between census years, the total figures are obtained by projecting the base census year's figure forward yearly. The increment is based on the annual total number of net additions to the stock (or net supply of housing). The series before 2001 has been adjusted to meet the 2001 Census estimates.

For pre 1991 estimates, the 1981 census did not include a direct count of dwellings but estimates have been made using the information about access which was recorded for each 'household space' (the living accommodation occupied or intended to be occupied by one household). The method used was to take the number of self-contained household spaces in permanent buildings, each of which must by definition correspond to a separate dwelling, and add to that figure an allowance for shared dwellings. This was done by assuming that on average 100 'not self contained' household spaces are equivalent to 25 separate dwellings (for Inner London where sharing is prevalent, this figure is reduced to 19). Since only a very small proportion of dwellings are shared, the dwelling stock estimates are not very sensitive to the number of household spaces assumed per shared dwelling. (All household spaces that are not in permanent buildings are assumed to be self-contained dwellings.)

The 1991 census did contain a direct count of dwellings. This was used for the figures for total stock for April 1991. However, when the model's projected total figure for 1991 was compared with that from the census, it was found that there was a slight shortfall. Hence one shortfall adjustment was spread over each of the years between 1981 and 1991. This is done by adding one tenth of the shortfall to each of the in between years.

For estimation of total stock figures since 1997/98 to 2006/07, the methodology is described in the first bullet point below. The implementation of this methodology followed a review of the data sources and methods used to compile these figures. The main changes related to how demolitions, slum clearance and conversion gains have been derived. The method of compiling stock figures by tenure for in between Census bench-marks for the same period is set out in the latter three bullet points below:

Total stock is derived from the latest Census benchmark and rolled forward using gains and losses of stock figures in the subsequent years. Gains are related to house building completions, net conversions, change of use, and from April 1997, non-permanent dwellings are also included. Losses are due to slum clearance, other demolitions, change of use and losses of non-permanent dwellings (again from 1997). Slum clearance is related to non Local Housing Authorities (LHA) owned dwellings that had been demolished after they have been declared unfit and closed by legal statues; the source of these data is the Housing Flows Reconciliation return. Other demolitions include LHA owned properties that had been demolished for whatever reasons, plus those non LHA owned properties that were demolished through development or road schemes. Hence total demolitions are the sum of slum clearance and other demolitions. Since 2004-05, data have been collected on total demolitions only.
The totals for the local authority stock are collected directly from authorities by the Department on the Housing Strategy Statistical Appendix returns. Vacant dwellings are included. These local authorities' figures include adjustments for council house sales and Large Scale Voluntary Transfers. Similarly, figures for the Registered Social Landlords stock are collected by the Tenant Services Authority (external link) on their Regulatory Statistical Returns (RSR).
The figures for privately rented stock are based on the Census benchmark updated by changes in the number of private renters relative to the total number of private renters and owner occupiers as shown by the Labour Force Survey (LFS). The calculation is done at a regional level and the LFS figures are smoothed to take account of sampling variability. The figures include dwellings owned by other Government Departments eg Ministry of Defence which are insignificantly small in number (see end of section on Tenure in General Housing Terms above).
The owner occupied stock is the residual of total stock and figures for the tenures above, and thus they include RSL shared equity and shared ownership dwellings, non-registered HA dwellings, vacant privately owned dwellings as well as all of the net gain in non-permanent dwellings since April 1997. The latter two of these are relatively small in number and it is considered that their effects on the figures are insignificant.

Net additions

The annual net additional dwellings figure, or net housing supply, is the absolute change in dwelling stock between 1 April and 31 March the following year. It is derived from the number of new build permanent dwellings; plus the net gain from dwelling conversions; plus the net gain of non dwellings brought into residential use; plus net additions from other gains and losses to the dwelling stock (such as mobile and temporary dwellings); less any demolitions during the financial year (see live table 111).

Year built of dwelling stock by region

The age distribution of the stock is estimated from the Survey of English Housing, in which householders are asked when their home was built. The survey data is on the basis of households (see Section 8 for specific definition used) rather than dwellings, but any differences will be negligible. Also, the age distribution will not include vacant dwellings. Like all surveys, the SEH is subject to random variation, but most estimates in this table will not vary by more than 1 or 2 percentage points from year to year as a result.

Vacants in Social Housing

Vacant local authority dwellings

The vacant dwellings in council ownership include dwellings closed for slum clearance. These closed dwellings are generally excluded from dwelling stock estimates as they are not habitable. Management vacants are those dwellings ready for immediate letting, or which will be available after only minor repairs.

Vacant RSL dwellings

These figures are based on data that is collected once a year from the annual Regulatory and Statistical Return (RSR) sent out to all RSLs. (The RSR is successor to the earlier HAR/10). The table is equivalent to that which provides similar information about Local Authority vacancy rates.