UK housing and planning statistics

Demand is one of the main themes found in housing statistics.

In this landscape, the demand theme covers both housing demands and housing needs.

Housing demand refers to the preference and ability to buy a house or to rent in the private rental sector. Housing demand affects and gets effected by the supply of housing through the housing market.

Housing need is different. It is based on value judgments about what is an adequate level of housing provision. Those who cannot afford to secure such housing in the market place are deemed to be in housing need.

A needs judgement involves both standards and affordability elements. Discussion of housing need often involves considering households of a particular type, such as:

• elderly people
• people with physical disabilities
• those who have had a mental illness or have learning difficulties
• travelling people, refugees, ex-offenders, abused women, young single homeless people

The provision of social housing is the main route for addressing housing need.

The demand theme has 4 sub-themes: occupancy density, household estimates, homelessness, and social housing.

Occupancy density is a sub-theme of demand.

Occupancy density covers whether a property has enough living space for the people living there to feel comfortable.

For statutory definitions for overcrowding, see the Housing Act 1985 (England and Wales) and the Housing (Scotland) Act 1987.

Roughly, each household requires 1 bedroom per:

• couple
• single adult (over the age of 21 in Scotland)
• child over the age of 16 (20 in Scotland)
• two children of the same sex under the age of 16 (between the ages of 10 and 20 in Scotland)
• two children of either sex under the age of 10

A household is then overcrowded if it has fewer bedrooms than needed to avoid undesirable sharing. A household counts as under-occupied if it has more bedrooms than needed to avoid undesirable sharing.

Household estimates is a sub-theme of demand.

Household estimates provide the number of households in UK countries based on population estimates. They are based on past population estimates.

Household estimates use trends of household formation rates found in the censuses. These trends are then applied to current population estimates.

For Scotland, the National Records of Scotland collect statistics on the number and type of households from council tax returns.

The household estimates theme has 1 sub-theme: projections.

Projections is a sub-theme of household estimates.

Household projections provide estimates of future households numbers. They do this by using population projections and a range of assumptions about household composition and make-up. These assumptions follow past trends.

The projections estimate the number and size of households. They assume that past trends in births, deaths, and migration continue.

Projections produced in this way do not account for:

• the effects of local or central government policies on future population levels and household composition
• changes in the lifestyles of the population

Homelessness is a sub-theme of demand.

A person is homeless if they have no accommodation in the UK or elsewhere. A person is also homeless if they have accommodation but cannot reasonably occupy it, for example because of a threat of violence.

Temporary accommodation can help address both an interim duty to accommodate and the full housing duty. That is, an applicant could have temporary accommodation given to them:

• during their investigation
• as part of relief of homelessness
• while waiting for a permanent offer of rehousing

Rough sleeping is a sub-section of homelessness and is defined as:

• people sleeping or bedded down in the open air (such as on the streets, in doorways, in parks or bus shelters)
• people in buildings or other places not designed for habitation (such as barns, sheds, car parks, cars, derelict boats, stations or 'bashes')

Statistics on statutory homelessness and rough sleeping get collected by local authorities.

Social housing is a sub-theme of demand.

In the UK, local authorities, registered social landlords, and the Northern Ireland Housing Executive provide social housing. This is for people on low incomes or with particular needs. Rents tend to be at below market rates, and tenants have more security of accommodation.

The social housing theme has 5 sub-themes: demographics, lettings, waiting lists, sales, and affordability.

Demographics is a sub-theme of social housing.

Demographics means the characteristics of a population. This can cover a wide range of aspects such as: age, sex, religion, ethnicity, education level, state of health, or what work people do.

The Census provides the most complete snapshot on the UK's demographics, and occurs once every 10 years. It asks a wide range of questions on ethnicity, religion, income, housing, and family make-up. Households must complete the census, though some questions are voluntary.

Each UK country also runs household surveys. These are smaller in scope (usually a few thousand households). They are designed to take a representative estimate of all households. Together, census and household survey data can estimate the current demographic make-up of the UK.

Tenure data gets collected as part of the Census and housing surveys. Because of this, demographics for specific tenure types can be measured.

Lettings is a sub-theme of social housing.

There are several types of providers of social housing in the UK:

• local authorities
• registered social landlords
• the Northern Ireland Housing Executive

English, Scottish, and Welsh local authorities collect statistics on the:

• characteristics of social housing tenants
• types of tenancy agreements
• housing trends

In England, private registered providers also provide these statistics via the Continuous Recording of Lettings system.

The lettings theme has 2 sub-themes: evictions, vacancies.

Evictions is a sub-theme of lettings.

Statistics on the eviction of tenants from social housing get recorded in each country as part of yearly statistical returns.

Statistics on social housing evictions can include:

• the reason why an eviction gets carried out, such as for anti-social behaviour or rent arrears
• the types of action taken, such as number of cases proceeding to court

For England and Wales, the Ministry of Justice collect statistics on the repossession of property by social landlords.

Vacancies is a sub-theme of lettings.

Vacancies in social housing get recorded in each country as part of yearly returns. A vacancy occurs when there is time between tenancies. A house will stay vacant if it needs to have repairs or refurbishment carried out, or while the next tenant is being found.

There are statistics available on vacancies of houses owned by local authorities and registered social landlords in England, Scotland and Wales. Some social sector vacancy statistics also get collected as part of Northern Ireland's House Conditions Survey.

Waiting lists is a sub-theme of social housing.

Local authorities in England and Wales manage waiting lists for their area so that they can prioritise who they give social housing to. In Scotland, registered social landlords also manage waiting lists.

Every local housing authority must have a scheme for choosing who to prioritise, and the procedure to use in allocating housing. The scheme is set up such that key vulnerable groups can have reasonable preference. In Scotland, private registered providers also control allocation policies for their housing.

Waiting lists can get affected by other factors. This includes reviews by local authorities to remove households who no longer need housing.

Statistics on waiting lists get collected by local authorities in all UK countries, but Wales does not collect these statistics centrally. Use waiting list statistics with caution. A household can get counted in more than one local authority as they can register on many waiting lists.

Sales is a sub-theme of social housing.

Social housing sales covers the selling of social housing to tenants or the transfer of stock to registered social landlords (except in Wales).

Right to Buy schemes are the main mechanism in which tenants of social housing can buy their homes. This type of scheme is no longer available in Scotland and Wales.

Other schemes are available such as:

• Right to Acquire (available in England but no longer available in Wales)
• Social Homebuy (England only)
• Shared ownership schemes

Historic time series data will include large scale transfers of local authority owned stock to registered social landlords (except in Wales).

The sales theme has 1 sub-theme: Right to Buy.

Right to buy is a sub-theme of sales.

A Right to Buy scheme allows eligible social housing tenants to buy their house at a discount. England and Northern Ireland both still run the scheme. A household's eligibility to Right to Buy in England and Right to Buy in Northern Ireland differ. Right to Buy schemes are no longer available in Wales or Scotland.

Statistics on Right to Buy sales get collected through local authority returns.

Affordability is a sub-theme of social housing.

Affordability is a measure of housing costs against a household's financial situation. This can be through comparing the price of a property or the price of housing costs, such as mortgage or rent payments or bills, to the income and wealth of a household.

Affordability ratios in England and Wales derive from house price data from Land Registry and income survey data.

The affordability theme has 1 sub-theme: housing costs.

Housing costs is a sub-theme of affordability.

Housing costs are a sub-section of affordability which focuses on the costs of running a property. This can include bills for:

• rent or mortgage repayments
• council taxes
• gas and electricity
• water and sewerage

Housing cost statistics are not collected as part of regular returns. Housing surveys have sections on income and outgoings, and this provides an estimate of housing costs in the UK.

Supply is one of the main themes found in housing statistics.

Housing supply is about the available stock of housing in the UK. Change in housing supply is affected by:

• the application and granting of planning permission for major construction to occur
• the construction of new houses
• the demolition of unsafe housing or the clearing to land for new housing developments
• the change of use of a building through conversions or expansions

All major building work in the UK must have permission from local planning authorities before they can start. Statistics on permissions, conversions, and new constructions then get collected by those authorities.

The supply theme has 4 sub-themes: land use and planning, demolitions, change of use, and housebuilding.

Land use and planning is a sub-theme of supply.

Land use and planning statistics covers several themes:

• planning application statistics, which including the number of applications to, and permissions given by, local planning authorities (in Scotland, number of applications with decisions are collected rather than total applications)
• Green Belt statistics, which includes the size, and change in size of designated Green Belt land within a local authority's area
• land use statistics, which cover developed and non-developed land use, and land use within flood zones and Green Belt areas
• land use change statistics, which includes changes of land use from non-developed to residential, and the density of housing

Planning statistics get collected by local planning authorities. Land use statistics get collected by the Ordnance Survey. The Department for Levelling Up, Housing and Communities (DLUHC) is then responsible for the analysis and publication of the statistics.

The land use and planning theme has 2 sub-themes: applications, permissions.

Applications is a sub-theme of land use and planning.

People or businesses may need to apply for planning permission before starting to:

• develop new residential or commercial properties
• make changes to or change the use of existing property

Statistics on the type of development and number of applications received get collected by the local planning authority.

Permissions is a sub-theme of land use and planning.

Once a person or business makes an application, the local planning authority must then give permission before work can go ahead.

Planning authorities can also give retrospective permission. This occurs if the developer has not applied for permission but the development does not go against planning rules.

Statistics on planning permission include:

• the type of developments which have had permission granted
• the percentage of applications that have had permission granted
• the speed of decision making on applications

These statistics get collected by local planning authorities.

Demolitions is a sub-theme of supply.

Demolition of a property can occur if the building is unsafe for living in, or to make way for new developments.

Statistics on demolitions get collected from local authorities, and can include information on:

• the tenure of the demolished building
• whether the demolition is to clear an unfit property or to renew an area through new development

Demolitions statistics are part of dwelling stock estimates as they reduce the available stock of housing

Change of use is a sub-theme of supply.

Change of use covers properties in which the original purpose or structure has undergone a change for the purposes of housing.

This can cover when a non-residential building gets converted into a residential building. Depending on the size of the property, this can become a multi-occupancy building, such as a block of flats. This can also cover when a large residential building gets separated into smaller individual units. This can include splitting a large house into two flats.

It can also cover extensions, where more space gets added to a property through expansions or extensions.

In some cases, a change of use requires planning permission from the local planning authority. This must happen before work can begin.

The change of use theme has 2 sub-themes: expansions, conversions.

Expansions is a sub-theme of change of use.

Expansions are when a property has its internal living-space increased. This can be through:

• the physical expansion of the structure, such as building a conservatory
• through the conversion of an attic or attached garage into a inhabitable space

If the planned expansion is over a certain size, or in a certain part of the property, then you must get planning permission. These size limits depend on whether the expansion is single story, or multi-story.

Conversions is a sub-theme of change of use.

Conversions are cases in which the original purpose or structure of a property has undergone a change for the purposes of housing.

This can cover cases where a non-residential building gets converted into a residential building. Depending on the size of the property, this can become a multi-occupancy building, such as a block of flats. This can also cover when a large residential building gets separated into smaller individual units. This can include splitting a large house into two flats.

Any intended conversions must have planning permission from the local planning authority. This must happen before building work can begin.

Housebuilding is a sub-theme of supply.

Building houses can increase the total available supply.

House-building is set by council planning policy. These policies may set a lower limit on the number of affordable housing units that a house-builder must build provide as part of a development.

The housebuilding theme has 2 sub-themes: new builds, affordable housing.

New builds is a sub-theme of housebuilding.

New build statistics covers any new construction of housing.

Funding for new houses can come from a variety of sources, including:

• local authorities
• private enterprises or private sector
• registered providers of social housing

One of the major sources of new build estimates derive from building inspection data and can include:

• the tenure of the completed house, such as social rent or shared ownership
• the type of house being build, such as flats or houses
• funding source, such as local authorities or private registered providers
• whether the location is urban or rural

Energy Performance Certificate (EPC) data on new houses are also collected. House-builders must provide EPCs for new house, conversion, or change of use produced.

Affordable housing is a sub-theme of housebuilding.

Affordable housing is a product for households who cannot access or afford housing at market rates. It is easy to confuse with housing affordability, which describes the cost of housing when compared to household income or assets.

Affordable housing does not have a legal definition. It is instead defined through policy and practice in each of the four nations. In general, houses deemed affordable cost less than market rates.

Affordable housing may be built, acquired, or converted as part of a larger development by local councils and housing associations to meet the needs of the area.

Affordable housing products sit across a range of tenure types, including rental and ownership schemes.

Data collected on affordable housing can include:

• the scheme used
• range of the value of the deposit
• property type, location, and value
• number of bedrooms
• and tenure types
• age of the buyer

depending on the country.

The affordable housing theme has 2 sub-themes: starts and completions, help to buy.

Starts and completions is a sub-theme of affordable housing.

Starts and completion statistics cover the beginning and end phases of the construction process. On how many houses has construction started on, and how many houses get completed.

Building a house can take many months. During that period, economic changes can happen which may force house-builders to pause construction or change the number of houses delivered. This means that completion statistics will not be the same as start statistics offset by a few months.

Statistics collected on starts and completions can include:

• the sector of the completed house, such as social rent or shared ownership
• funding source, such as local authorities or private registered providers
• whether the location is urban or rural

Help to buy is a sub-theme of affordable housing.

Help to Buy schemes help you buy a house if you can't afford the total cost.

Each UK country runs their own Help to Buy schemes, and they may work in a different manner. These can include:

• equity loan, a low-interest loan towards a deposit on a home
• shared ownership schemes, where you part buy and part rent
• a rent to buy scheme that will pay you a rebate on some of the rent you've paid
• government backed savings schemes, which will give you a bonus to add to your deposit

Eligibility requirements are different for each country, and can include:

• a limit on the total cost of the house
• a minimum amount that the applicant must contribute towards the deposit
• being limited to new builds only
• needing to buy through registered house-builders
• not being sub-let or rented out after sale
• the applicant not owning another property

Shared equity schemes will cover up to a certain percentage of the total cost of the house, with a mortgage making up the rest.

Data collected on Help to Buy schemes can include property price and type, buyer deposit level and type of buyer, and total applicant income.

Stock is one of the main themes found in housing statistics.

Stock covers the quantity and characteristics of housing currently available in the UK.

This can include:

• the physical make-up of UK housing.
• the state of the housing stock.
• vacant properties.
• the change in ownership or occupancy of a property.

Statistics get collected through council tax or registered social landlord returns, or through Census and housing conditions surveys. The Scottish Housing Conditions Survey does not collect statistics on vacant properties, change in ownership or occupancy of a property.

The stock theme has 4 sub-themes: dwelling stock, vacant dwellings, quality and standards, and transactions.

Dwelling stock is a sub-theme of stock.

Dwelling stock is the term used to cover all housing in the UK. It includes:

• the number, type, and size of properties
• what the tenure is of the inhabitants
• what the land tenure of the property is

Statistics on dwelling stock gets collected through census, housing survey, council tax or registered social landlord returns.

The dwelling stock theme has 3 sub-themes: tenure, dwelling type, and land tenure.

Tenure is a sub-theme of dwelling stock.

Tenure describes how a household has a right to live in their home.

This is can be through owning the property (outright or with a mortgage), or renting from a private landlord, a council, or housing association.

Dwelling type is a sub-theme of dwelling stock.

Dwelling type describes the make up of the housing stock.

Dwellings are usually flats or houses. Flats can be part of a high-rise or low-rise building or part of a conversion. Houses are either detached, semi-detached, or terraced.

Land tenure is a sub-theme of dwelling stock.

In England and Wales, land tenure of a property can be either freehold, leasehold, or commonhold.

The freeholder of the property owns both the building, and the land upon which the building sits. They are responsible for the maintenance of the property.

A leaseholder owns the right to inhabit a property, but they do not own the property or the land where the property sits. This particularly common for flats within a larger building. They have the right to occupy the property for a specific length of time, and after that time, the lease returns to the freeholder. Leaseholders have to pay land rent, a service charge, and upkeep costs to the freeholder.

A commonholder owns an indefinite freehold on a property within a multi-occupancy building. They also share ownership and responsibility for the building's common areas and services with other commonholders in the building.

Vacant dwellings is a sub-theme of stock.

Vacant dwellings are those properties which do not have any inhabitants at the time of recording. Some countries collect statistics on vacant properties as part of council tax returns. In England and Wales, owners of properties must declare the status of the property to be eligible for reduced council tax rates. In Scotland, reduced council rates are not available to vacant properties or second homes.

Properties can be vacant due to repossession, being unfit for living in, as a second home or as a vacant possession.

The vacant dwellings theme has 2 sub-themes: second homes, repossessions.

Second homes is a sub-theme of vacant dwellings.

If a person owns more than one house, and the houses they do not live in are for their own personal use, then these houses are then defined as second homes. Second homes are often used as holiday homes or are kept for work reasons and see use for only part of a year.

Some countries collect statistics on second homes as part of council tax returns. In England and Wales, owners of properties must declare the status of the property to be eligible for reduced council tax rates. In Scotland, reduced council rates are not available to vacant properties or second homes.

Repossessions is a sub-theme of vacant dwellings.

Laws on repossession differ across the UK, with different requirements on lenders during the process. In general, repossession of a mortgaged property by the mortgage lender can occur if mortgage repayments go into arrears.

Before repossession can occur, the borrower and lender must fail to agree on terms for a repayment scheme. If such an agreement fails, then the case proceeds to court.

There are several possible outcomes from such a court case, but repossession can only occur if the judge gives a court order to that affect. Failure of the borrower to vacate the property in the time given by the court can lead to the court passing an eviction order.

Quality and standards is a sub-theme of stock.

Quality and standards describes the physical characteristics and property attributes of the UK's housing stock. Is it safe and secure, and does it meet appropriate standards for living conditions?

This can include:

• the size and age of a property
• the property's energy efficiency
• whether the property is hazard free and in a good state of repair

In legislation, landlords of social housing must meet housing standards.

Statistics on housing quality get collected as part of housing surveys. The Census collects some statistics on quality, such as the size of a property.

The quality and standards theme has 2 sub-themes: non-decent estimates, energy efficiency.

Non-decent estimates is a sub-theme of quality and standards.

The definition for non-decent housing vary across countries, but generally they are those properties that do not meet a minimum stadard of habitability. This can be caused by:

• being in poor repair
• not meeting health and safety standards
• lacking in modern facilities
• being incapable of maintaining a comfortable temperature for occupants

Providers of social housing must ensure that the properties they let out meet minimum housing quality standards.

Energy efficiency is a sub-theme of quality and standards.

Energy efficiency is a measure of how the construction of a building, and the state of its fittings, affects how much energy it uses.

Poor energy efficiency of a property drives up the cost of household bills, which can be a cause of fuel poverty. It also drives up domestic energy use. This can contribute towards greater levels of carbon emission.

There are schemes available which provide financial aid to homeowners to improve the energy efficiency of their home.

This can include:

• improvements to insulation
• double glazing
• heating
• draught-proofing
• renewable energy generation

Property landlords are legally obligated to provide Energy Performance Certificates (EPC) to potential tenants. This is to inform tenants of the potential cost of household bills.

Statistics on energy efficiency get derived from information collected as part of housing condition surveys. The Census also collects some statistics related to energy efficiency, such as the type of central heating. Energy Performance Certificate data on new houses are also collected. House-builders must provide EPCs for each new house, conversion, or change of use produced.

Transactions is a sub-theme of stock.

Transactions track the changes in ownership or occupants of properties.

This can be through:

• recording changes in rental or sale prices
• tracking the number of evictions
• by measuring the property rental or sales markets

The transactions theme has 3 sub-themes: lettings, evictions, and sales.

Lettings is a sub-theme of transactions.

Lettings relate to the type and duration of tenancy agreements, whether they are a social or private letting, and what the rental costs are.

Statistics on the letting of social housing gets collected by each UK country's regulator of social housing as part of annual returns.

Private sector rental data is not collected through standard returns. Organisations can estimate these statistics based on:

• advertised rents
• private landlord and letting agent returns
• housing surveys

These statistics provide average rental prices for properties at a local authority level, and can get broken down by the number of rooms.

The lettings theme has 1 sub-theme: peer to peer lettings.

Peer to peer lettings is a sub-theme of lettings.

Peer to peer letting is where a householder will sublet all or part of their dwelling through an internet service rather than using an agent as an intermediary.

Peer to peer letting started out un-regulated. But now schemes are in place to regulate the market, this includes HMRC's Rent a Room Scheme.

Evictions is a sub-theme of transactions.

In rented property, eviction is the removal of a tenant from the property by the landlord. To get an eviction notice, a landlord must apply to a court for one, and must provide a reason why they are calling for eviction.

Valid reasons for eviction include breach of contract by the tenant, such as missing rental payments. In England and Wales, landlords can also repossess a property though a Section 21 or 'no-fault' eviction. For a Section 21 eviction, a landlord does not need to provide a reason to evict. But, tenants must be on a short-term lease and have a two month period to vacate.

If an owner has a mortgage on a property and fails to meet repayments, then repossession by the mortgage lender of the property is possible. If the occupier of the property does not vacate within the timeframe given in the repossession order, then a court can pass an eviction order.

Sales is a sub-theme of transactions.

Sales represent the price paid to buy a property and the number of properties sold.

House price indexes measure the price change of housing using sales data. Data is available at a national and regional level, as well as counties, local authorities and London boroughs.

Housing experience is one of the main themes found in housing statistics.

Housing experience refers to the level of happiness that people express in relation to their housing situation. It can include the quality of life people experience while living in their home, and the physical state of the property.

Example themes are:

• what is the composition, ethnicity, nationality, education level, health, and economic status of the household?
• what are the aspirations of those living at the property?
• what are the views on the landlord or local area?
• does the property feel over-crowded for the number of occupants?
• is the property safe for habitation and in a state of good repair?
• does a house meet the accessibility needs of people with disabilities?
• are household bills affordable?

The Census provides the most comprehensive overview of some of these themes and occurs once every 10 years. It is compulsory for households to complete the census, though some questions are voluntary.

To help fill in the data gaps that occur between each census, government bodies use household surveys to take a snapshot of the state of housing in the UK.

These include:

• the English Housing Survey
• the Scottish Household Survey
• the House Conditions Survey (Northern Ireland)
• the Continuous Household Survey
• the Welsh Housing Conditions Survey
• the National Survey for Wales

These act like smaller censuses, each with a sample size of a few thousand households who agree to take part. They are designed to take a representative estimate of all households. They cover many of the same areas that the Census will cover.

The housing experience theme has 1 sub-theme: housing conditions.

Housing conditions is a sub-theme of housing experience.

Housing conditions is an umbrella term for the physical state of housing in the UK.

It can cover themes such as:

• energy efficiency of the house
• fire safety
• structural integrity of the house
• disrepair
• damp and mould
• over-crowding

Housing conditions statistics get collected through the English and Scottish Housing Surveys and the Welsh and Northern Irish Housing Conditions Surveys.

External factors is one of the main themes found in housing statistics.

Housing in the UK does not exist in a bubble. There are various external factors that can cause knock-on effects on housing.

External factors can also affect each other. For example, demographic changes put pressure on governments to enact new housing policies if the housing market is not meeting current needs.

Economic and demographic changes can also affect the political climate. This, in turn, will affect the type of housing or economic policies that governments enact.

The external factors theme has 4 sub-themes: housing policies, political climate, economic change, and changing demographics.

Housing policies is a sub-theme of external factors.

Housing policies are initiatives set up by government bodies to tackle wider housing issues. As housing is a devolved matter, these initiatives are only applicable in the country which enacted them.

Some examples of major housing policies include the Right to Buy and Help to Buy schemes.

The Right to Buy scheme is a policy that gives renters of council houses and some social housing providers the right to buy the home they live in. All four UK countries have enacted right to buy schemes, though Scotland and Wales have now ended theirs.

The Help to Buy scheme is a policy that helps people who can't afford to buy a property. This can be through equity loans, shared ownership, rent to buy, or government backed deposit savings schemes. Not everyone can use a Help to Buy scheme, as there are various eligibility criteria.

As a part of running the schemes, the bodies responsible for running the schemes will collect statistics on them. This can include property price and type, deposit level and type of buyer, and total applicant income.

Political climate is a sub-theme of external factors.

Political climate is the wider political situation which may have an indirect effect on housing.

Housing is a devolved policy area so each UK country has some say over how much funding is allocated to encouraging housing development. This spending has to be balanced against other priorities for example healthcare or education.

New or improved transport links or focused development may have an impact on housing in particular areas.

Changes to migration policy may have an impact on demand for housing.

Views on the environment and climate change may influence the development and design of housing, either in terms of more energy efficient housing or where housing should or should not be built.

Opinion polls are often used to measure the public's view on priorities.

Economic change is a sub-theme of external factors.

The economy refers to the system in which people earn their living. This is usually split into things people make, called goods, and the things people do, called services.

The economy is in a state of constant change, growing and contracting in reaction to political and demographic pressures. Changes in the economy of one sector can have a knock-on affect on other sectors.

For example, changes in the cost of mining and manufacturing raw building materials (such as bricks, mortar, timber, and glass). This can affect the cost of construction of new houses, making them less profitable to build. If the cost gets too high, house-builders might build fewer houses.

Another example would be an increase in interest rates, which will increase the cost of getting a mortgage. This can put people off buying a house. Interest rate increases can also increase the cost of some existing mortgages. The monthly repayment of mortgages might become too expensive, and so households might find themselves going into arrears.

Government bodies can set housing or economic policies with the aim of aiding sectors of the economy.

Changing demographics is a sub-theme of external factors.

Demographics means the characteristics of a population. This can cover a wide range of aspects such as: age, sex, religion, ethnicity, education level, state of health, or what line of work people are in.

The UK's demographics change over time. But it is how the UK's demographics change that can have a profound effect on housing needs across the UK.

A growing or shrinking population size means that the UK needs more or fewer houses. Internal migration also means that these houses need to be in the right parts of the country.

Changes in the average size of a family means that houses need to be bigger or smaller to avoid over-crowding.

An ageing population, especially those with healthcare issues, may need more specialised housing. This might include more single-level housing (like bungalows) or care housing with wardens.

How well-off the population is can affect the type of housing tenure people have. A more affluent society might see more people living in homes that they own outright and may need less social housing.

Meeting these housing needs can be through a mix of organic responses by house-builders and the housing market, and through government-backed schemes.

The Census provides the most comprehensive snapshot on the UK's demographics, and occurs once every 10 years. It asks a wide range of questions on ethnicity, religion, income, housing, and family make-up. It is compulsory for households to complete the census, though some questions are voluntary.

Each UK country also runs annual household surveys, which are much smaller in scope (usually a few thousand households). Together, Census and household survey data can estimate the current demographic make-up of the UK, and can give us an idea on how it will change.