A semi-detached house (often abbreviated to semi) is a single-family
duplex dwelling that shares one common
wall
A wall is a structure and a surface that defines an area; carries a load; provides security, shelter, or soundproofing; or serves a decorative purpose. There are various types of walls, including border barriers between countries, brick wal ...
with its neighbour. The name distinguishes this style of construction from
detached houses, with no shared walls, and
terraced house
A terrace, terraced house ( UK), or townhouse ( US) is a type of medium-density housing which first started in 16th century Europe with a row of joined houses sharing side walls. In the United States and Canada these are sometimes known as row ...
s, with a shared wall on both sides. Often, semi-detached houses are built in pairs in which each house's layout is a mirror image of the other's.

Semi-detached houses are the most common property type in the United Kingdom (UK). They accounted for 32% of UK housing transactions and 32% of the English housing stock in 2008. Between 1945 and 1964, 41% of all properties built were semis. After 1980, the proportion of semis built fell to 15%.
History of the semi-detached house in the United Kingdom
Housing the rural working classes
Housing for the farm labourer's family in 1815 typically had one downstairs room with an extension for a
scullery (for washing) and
pantry
A pantry is a room or cupboard where beverages, food, (sometimes) dishes, household cleaning products, linens or provisions are stored within a home or office. Food and beverage pantries serve in an ancillary capacity to the kitchen.
Etymol ...
(for storing food), and two bedrooms upstairs. The house would be of brick, stone if it occurred locally, or
cob (soil and fibre) on a wooden frame. These houses were unsanitary, but the biggest problem was that there were simply too few of them. Population was increasing rapidly (see table), and after the
inclosure acts labourers could not find spare land to build their own homes. Homebuilding was thus the responsibility of a
landowner or speculative builder.
In the late 18th century,
estate villages followed local architectural styles. This later changed as landowners adopted model designs from
pattern books. By the early 19th century, landowners were typically using a "picturesque" style, and building double cottages as a way to reduce cost. In 1834, Edinburgh architect George Smith wrote "this species of cottage can be built cheaper than two single ones, and, in general, these double cottages are found to be warmer and fully as comfortable as single ones".
Housing the urban working classes
Life in Great Britain during the Industrial Revolution changed drastically. At the same time as the huge increase in the population of the rural counties, there was
an even greater shift in population from the impoverished land to the large towns and to cities (
urbanisation
Urbanization (or urbanisation in British English) is the population shift from rural to urban areas, the corresponding decrease in the proportion of people living in rural areas, and the ways in which societies adapt to this change. It can also ...
). Society was restructuring, with the working classes dividing into artisans and labourers. In the cities, labourers were housed in overcrowded
tenement blocks,
rookeries and
lodging houses, and philanthropic societies aimed to improve conditions. The rural Labourers' Friend Society expanded in 1844 and was reconstituted as the
Society for Improving the Condition of the Labouring Classes. In their 1850 publication ''The Dwellings of the Labouring Classes'', written by
Henry Roberts, the society laid out plans for model 'semi-detached' cottages for workers in towns and the city. However, the first properties they built were tenements and lodging houses.
In 1866 the
built Alexander Cottages at
Beckenham
Beckenham () is a town in Greater London, England, within the London Borough of Bromley. Prior to 1965, it was part of Kent. It is situated north of Elmers End and Eden Park, east of Penge, south of Lower Sydenham and Bellingham, and west ...
in Kent, on land provided by the
Duke of Westminster. The development initially comprised 16 pairs of semis. By 1868, they had built 164 semis.
In
Birmingham
Birmingham ( ) is a City status in the United Kingdom, city and metropolitan borough in the metropolitan county of West Midlands (county), West Midlands, within the wider West Midlands (region), West Midlands region, in England. It is the Lis ...
,
Wolverhampton
Wolverhampton ( ) is a city and metropolitan borough in the West Midlands (county), West Midlands of England. Located around 12 miles (20 km) north of Birmingham, it forms the northwestern part of the West Midlands conurbation, with the towns of ...
and
the Potteries
The Staffordshire Potteries is the industrial area encompassing the six towns Burslem, Fenton, Staffordshire, Fenton, Hanley, Staffordshire, Hanley, Longton, Staffordshire, Longton, Tunstall, Staffordshire, Tunstall and Stoke-upon-Trent, Stoke ( ...
there was a tradition dating from the 1790s of artisans saving through mutual funds and
friendly societies. In the 1840s, the
permanent building society model was adopted. The Woolwich Equitable was founded in 1847, the Leeds Permanent in 1848 and Bradford Equitable in 1851. Artisans could invest and then borrow a sum for a mortgage on their own property.
Model villages
In the wool towns of Yorkshire, three factory-owning families built villages for their workers. In each, there was a hierarchy of houses:
long terraces for the workers, larger houses in shorter terraces for the overlookers (overseers), semi-detached houses for the junior managers, and detached houses for the elite. The first such village was built by
Colonel Edward Ackroyd, at
Copley, West Yorkshire, between 1849 and 1853, the second by
Sir Titus Salt at
Saltaire
Saltaire is a Victorian model village near Shipley, West Yorkshire, England, situated between the River Aire, the railway, and the Leeds and Liverpool Canal. Salts Mill and the houses were built by Titus Salt between 1851 and 1871 to allo ...
(1851–1861), and the third was the West Hill Park Estate in
Halifax built by
John Crossley.
Model village
A model village is a mostly self-contained community, built from the late 18th century onwards by landowners and business magnates to house their workers. "Model" implies an ideal to which other developments could aspire. Although the villages ...
s in Lancashire followed, with developments like
Houldsworth Village. Semi-detached housing in
colliery
Coal mining is the process of extracting coal from the ground or from a mine. Coal is valued for its energy content and since the 1880s has been widely used to generate electricity. Steel and cement industries use coal as a fuel for extra ...
villages was rare; status here was determined by the length of the terrace.
The development of
Port Sunlight
Port Sunlight is a model village in the Metropolitan Borough of Wirral, Merseyside, England. It is located between Lower Bebington and New Ferry, on the Wirral Peninsula. Port Sunlight was built by Lever Brothers to accommodate workers in ...
and
Bournville was important. The Port Sunlight model village was begun in 1887.
William Lever
William Hesketh Lever, 1st Viscount Leverhulme (; 19 September 1851 – 7 May 1925) was an English industrialist, philanthropist, and politician. Educated at a small private school until the age of nine, then at church schools, he joined his f ...
used architects William Owen and his son Segar Owen and stated in 1888 that:
It is my and my brother's hope, some day, to build houses in which our work-people will be able to live and be comfortable – semi-detached houses with gardens back and front, in which they will be able to know more about the science of life than they can in a back-to-back slum.
At Bournville in 1879 the
Cadbury
Cadbury, formerly Cadbury's and Cadbury Schweppes, is a British multinational confectionery company owned by Mondelez International (spun off from Kraft Foods) since 2010. It is the second-largest confectionery brand in the world, after Mars. ...
development started with a detached house for the manager and six pairs of semis with large gardens for key workers. By 1895 the village was made up of semis and short terraces, showing that a low density layout could be a practical possibility even for the working classes. The examples of Bournville and Port Sunlight were seized on by
Ebenezer Howard, and they became key models for the
Garden City movement
The garden city movement was a 20th century urban planning movement promoting satellite communities surrounding the central city and separated with Green belt, greenbelts. These Garden Cities would contain proportionate areas of residences, i ...
.
Housing the middle classes
The middle class became an important and expanding group in the 19th century. With industrialisation came material gain to the capitalist entrepreneur. New professions came into existence to serve their needs: insurers, engineers, designers. The growth in the population required more architects, lawyers, teachers, doctors, dentists and shopkeepers. Hierarchical tiers emerged within the middle class, each watching each other's status. According to ''A New system of Practical Domestic Economy'' (1820–1840), being middle class required an income of £150 p.a. or more. In 1851, 3 million out of a total population of 18 million in the UK would have been considered to be middle class.
Semi-detached houses for the middle class began to be planned systematically in late 18th-century
Georgian architecture
Georgian architecture is the name given in most English-speaking countries to the set of architectural styles current between 1714 and 1830. It is named after the first four Monarchy of the United Kingdom, British monarchs of the House of Han ...
, as a
suburb
A suburb (more broadly suburban area) is an area within a metropolitan area. They are oftentimes where most of a metropolitan areas jobs are located with some being predominantly residential. They can either be denser or less densely populated ...
an compromise between the
terraced house
A terrace, terraced house ( UK), or townhouse ( US) is a type of medium-density housing which first started in 16th century Europe with a row of joined houses sharing side walls. In the United States and Canada these are sometimes known as row ...
s close to the city centre, and the detached "
villa
A villa is a type of house that was originally an ancient Roman upper class country house that provided an escape from urban life. Since its origins in the Roman villa, the idea and function of a villa have evolved considerably. After the f ...
s" further out, where land was cheaper. There are occasional examples of such houses in town centres going back to medieval times. Most early examples are in areas such as
Blackheath,
Chalk Farm
Chalk Farm is a small urban district of north west London, lying immediately north of Camden Town, in the London Borough of Camden.
History
Manor of Rugmere
Chalk Farm was originally known as the Manor of Rugmere, an estate that was mentio ...
and
St John's Wood
St John's Wood is a district in the London Borough of Camden, London Boroughs of Camden and the City of Westminster, London, England, about 2.5 miles (4 km) northwest of Charing Cross. Historically the northern part of the Civil Parish#An ...
, then considered suburbs but now part of
Inner London
Inner London is the group of London boroughs that form the interior part of Greater London and are surrounded by Outer London. With its origins in the bills of mortality, it became fixed as an area for statistics in 1847 and was used as an area ...
. Richard Gillow of Lancaster (1734–1811) was designing 'semis' or pairs of houses in that town as early as 1757, in Moor Lane. The earliest identifiable surviving pair is that built in 1759 on Cable Street (now facing the bus station and partly demolished) for Captain Henry Fell and Samuel Simpson. The specification for this building still survives in the Gillow archives.
In these early years a common style was a row of houses in which several pairs of semi-detached houses are linked by a wall along the frontage. An example is The Paragon in Blackheath, where a blank
colonnade
In classical architecture, a colonnade is a long sequence of columns joined by their entablature, often free-standing, or part of a building. Paired or multiple pairs of columns are normally employed in a colonnade which can be straight or curv ...
runs between the houses. Most early examples were relatively large houses with access at the rear.
During the 19th century, a father and son architectural partnership,
John Shaw Sr. and
John Shaw Jr., drew up designs for semi-detached housing in London. Examples of their work can be seen in
Chalk Farm
Chalk Farm is a small urban district of north west London, lying immediately north of Camden Town, in the London Borough of Camden.
History
Manor of Rugmere
Chalk Farm was originally known as the Manor of Rugmere, an estate that was mentio ...
, North London.
John Nash, better known for his
Regency terraces, built some semi-detached villas either side of the
Regent's Canal. These were styled to appear as substantial single detached villas with the entrances to the side. Similarly, the landscape gardener
John Claudius Loudon
John Claudius Loudon (8 April 1782 – 14 December 1843) was a Scottish botanist, garden designer and author, born in Cambuslang in 1782. He was the first to use the term arboretum in writing to refer to a garden of plants, especially trees, co ...
built a pair of semi-detached villas fashioned to appear as a single house in
Porchester Terrace in 1825. In his 1838 book ''The'' ''Suburban Gardener and Villa Companion'' he gives advice on how to disguise the join between the houses by using false windows.
Late 19th century and 20th century
The
Public Health Act 1875
The Public Health Act 1875 ( 38 & 39 Vict. c. 55) is an act of the Parliament of the United Kingdom, one of the Public Health Acts, and a significant step in the advancement of public health in England.
Its purpose was to codify previous me ...
described the structure and required minimum size of
terraced houses
A terrace, terraced house ( UK), or townhouse ( US) is a type of medium-density housing which first started in 16th century Europe with a row of joined houses sharing side walls. In the United States and Canada these are sometimes known as row ...
and the street pattern that towns had to adopt. This made it difficult to place a semi in a large garden. The law stated that the building lines should be 11m apart, and that there should be rear access to allow the removal of
nightsoil. In 1875, it was thought that having a
privy inside the house was unhealthy. Cold water came from a stand pipe in the yard, and lighting was by candle or by
gas mantles. Heating and cooking was done by coal, and hot water was boiled in kettles on the
living room range. Kitchens were rare – the wet activities were done outside or in the
scullery. Later, water was piped to the house, and some living room fires had a
back boiler for heating.
During the First World War the
Tudor Walters Report was published, setting standards for the accommodations needed for returning soldiers, dubbed "
homes fit for heroes". The
Housing, Town Planning, &c. Act 1919 (Addison Act) incorporated those recommendations including one that allowed for housing based on the
Radburn design. In this design, small clusters of up to 15 houses would circle small
cul-de-sac
A dead end, also known as a ''cul-de-sac'' (; , ), a no-through road or a no-exit road, is a street with only one combined inlet and outlet.
Dead ends are added to roads in urban planning designs to limit traffic in residential areas. Some d ...
s of a district feeder road. This tipped the balance away from short terraces towards pairs of semi-detached houses. The housing density was initially generous, but was reduced in 1923 after a change of government from the
Liberal Party
The Liberal Party is any of many political parties around the world.
The meaning of ''liberal'' varies around the world, ranging from liberal conservatism on the right to social liberalism on the left. For example, while the political systems ...
to the
Conservative Party.

After the Second World War, there was a chronic shortage of houses. In the short term this was relieved by the construction of
prefabricated houses with a ten-year life. The successor was the
pre-cast reinforced concrete semi-detached house. Although the frame was concrete the exterior panels were often traditional brick, so the final building was visually indistinguishable from a traditionally built house.
The recommendations of the
Parker Morris Committee became mandatory for all public housing from 1967 till 1980. Initially the private sector adopted them too, but gradually lowered their standards.
Outside the United Kingdom and Ireland
Although semi-detached housing is built throughout the world, it is generally seen as particularly symbolic of the
suburbanisation of the
United Kingdom
The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a country in Northwestern Europe, off the coast of European mainland, the continental mainland. It comprises England, Scotlan ...
and
Ireland
Ireland (, ; ; Ulster Scots dialect, Ulster-Scots: ) is an island in the North Atlantic Ocean, in Northwestern Europe. Geopolitically, the island is divided between the Republic of Ireland (officially Names of the Irish state, named Irelan ...
, or post-war homes in
Canada
Canada is a country in North America. Its Provinces and territories of Canada, ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, making it the world's List of coun ...
. In
Toronto
Toronto ( , locally pronounced or ) is the List of the largest municipalities in Canada by population, most populous city in Canada. It is the capital city of the Provinces and territories of Canada, Canadian province of Ontario. With a p ...
, the semi-detached house was a major building type during both the pre and post-war periods. In
New England
New England is a region consisting of six states in the Northeastern United States: Connecticut, Maine, Massachusetts, New Hampshire, Rhode Island, and Vermont. It is bordered by the state of New York (state), New York to the west and by the ...
, some other parts of the United States, and occasionally in Canada, this style is colloquially called a "
duplex''"''. Elsewhere, however, "duplex" refers to a building comprising two flats/apartments, one above the other; this is also referred to as a "two-flat'. Semi-detached houses are typically referred to as 'twins' or 'double-blocks' in the
Mid-Atlantic region (particularly in
Pennsylvania
Pennsylvania, officially the Commonwealth of Pennsylvania, is a U.S. state, state spanning the Mid-Atlantic (United States), Mid-Atlantic, Northeastern United States, Northeastern, Appalachian, and Great Lakes region, Great Lakes regions o ...
).
Australia
In
Australia
Australia, officially the Commonwealth of Australia, is a country comprising mainland Australia, the mainland of the Australia (continent), Australian continent, the island of Tasmania and list of islands of Australia, numerous smaller isl ...
, a semi-detached house is also known as a "duplex". Townhouses may be apparently similar to semi-detached houses, but a semi-detached house sits on a single property, owned in its entirety by the owner of the semi-detached house, whereas townhouses sit on a shared property. The type of real property title held is therefore different: a semi-detached home is generally held as a
Torrens title
Torrens title is a land registration and land transfer system in which a state creates and maintains a register of land holdings, which serves as the Incontrovertible evidence, conclusive evidence (termed "Defeasible reasoning#Political and judic ...
d property, while a
townhouse
A townhouse, townhome, town house, or town home, is a type of Terraced house, terraced housing. A modern townhouse is often one with a small footprint on multiple floors. In a different British usage, the term originally referred to any type o ...
is a
Strata titled unit. Semi-detached houses come only in pairs, whereas there may be more than two townhouses attached together. In
Sydney
Sydney is the capital city of the States and territories of Australia, state of New South Wales and the List of cities in Australia by population, most populous city in Australia. Located on Australia's east coast, the metropolis surrounds Syd ...
, semi-detached houses were briefly popular at the beginning of the 20th century and many examples may be found in inner suburbs such as
Drummoyne. However, this style quickly gave way to the 'modern' style of detached housing which allowed better motor vehicle access, amongst other benefits.
Canada
The semi-detached house was seen as a good fit for downtown
Toronto
Toronto ( , locally pronounced or ) is the List of the largest municipalities in Canada by population, most populous city in Canada. It is the capital city of the Provinces and territories of Canada, Canadian province of Ontario. With a p ...
's narrow lots early in the city's history. In the late 19th century semis were built in areas such as
The Annex
The Annex is a neighbourhood in Downtown Toronto, Ontario, Canada. The traditional boundaries of the neighbourhood extend north to Dupont Street, south to Bloor Street, west to Bathurst Street (Toronto), Bathurst Street and east to Avenue Road, ...
and
Cabbagetown in assorted styles: Gothic Revival, Queen Anne, Second Empire,
bay-and-gable
The bay-and-gable is a distinct residential architectural style that is ubiquitous in the Old Toronto, older portions of Toronto, Ontario, Canada. The most prominent feature of the style is a large bay window that usually covers more than half the ...
.
Semi-detached homes continued to be built in the post-war period, often alongside detached types such as the
bungalow
A bungalow is a small house or cottage that is typically single or one and a half storey, if a smaller upper storey exists it is frequently set in the roof and Roof window, windows that come out from the roof, and may be surrounded by wide ve ...
. They remain popular with developers as they are cheaper to build than detached houses. According to the 2006 census, Toronto had more than 139,000 semis, more than any other Canadian city by a wide margin. Red-brick semis are a common sight throughout downtown and older suburbs.
Cultural references
* ''The Semi-Detached House'' (1859) is the first novel by
Emily Eden. followed the next year by ''The Semi-Attached Couple''.
John Sutherland described the former as "an accomplished study in the social contrasts of aristocratic style, bourgeois respectability and crass vulgarity."
[John Sutherland: ''Longman Companion to Victorian Fiction'' (1988), quoted in ''XIX Century Fiction'', Part I, A–K (Jarndyce, Bloomsbury, 2019).]
* "
Semi-Detached, Suburban Mr. James
"Semi-Detached, Suburban Mr. James" is a song written by songwriters Geoff Stephens and John Carter (English musician), John Carter, recorded by English pop group Manfred Mann in 1966. Previous to this, it was recorded by the band Herbie's People ...
", written and performed by
Manfred Mann
Manfred Mann were an English Rock music, rock band formed in London in 1962. They were named after their keyboardist Manfred Mann (musician), Manfred Mann, who later led the successful 1970s group Manfred Mann's Earth Band. The group had two l ...
, is a satirical song about a lost love marrying a boring man from semi-detached suburbia. It was
released in 1966 and reached No. 2 in the UK charts.
* ''
Semi-Detached Mock Tudor'' is a
live album
An album is a collection of audio recordings (e.g., music) issued on a medium such as compact disc (CD), vinyl (record), audio tape (like 8-track or cassette), or digital. Albums of recorded sound were developed in the early 20th centur ...
by
Richard Thompson.
* "My Pink Half of The Drainpipe", written and performed by the
Bonzo Dog Doo-Dah Band
The Bonzo Dog Doo-Dah Band (also known as the Bonzo Dog Band or the Bonzos) was created by a group of British Art school, art-school students in the 1960s. Combining elements of music hall, trad jazz and psychedelic music, psychedelia with sur ...
, satirises neighbourly relations and ownership of property, referring to the practice of each family painting only one half of the drainpipe that runs down the centre of the dividing line between properties.
* “Wisemen” is a song written and performed by British artist James Blunt, and refers to three wise men having a “semi” by the sea.
See also
*
Single-family detached home
A single-family detached home, also called a single-detached dwelling, single-family residence (SFR) or separate house is a free-standing residential building. It is defined in opposition to a multi-family residential dwelling.
Definitions ...
*
Linked house
References
Citations
Sources cited
*
*
*
*
* Sir
John Summerson, ''Georgian London,'' (1945), 1988 revised edition, Barrie & Jenkins, . (Also see revised edition, edited by
Howard Colvin, 2003)
*
*
External links
The Semi-Detached Houseby Hon. Emily Eden (1797-1869), published London: R. Bentley, 1859.
{{Room
House types