PLANNING - WHAT TYPE OF HOUSE DO I HAVE?

What type of house do I have, and why does it matter?

What type of house do you have?  It seems like a simple question, but the answer isn't always straightforward.  First though, why am I even asking?  It's because the type of house you have makes a significant difference when applying for planning approval, and when adding a 'permitted development' extension to that house.  

Planning legislation allows for 4 different types of dwelling:

- Detached house

- Semi-detached house

- Terraced house

- Flats

Detached houses are allowed to build a 4m deep extension to the rear under permitted development rights, while semi-detached and terraced houses can only build to 3m deep.

Detached and semi-detached houses can add 50cubic metres to their roof under PD rights, but terraced houses are only allowed 40cubic metres.  

So how are these types of homes defined?

Detached

Detached houses share no party walls with any neighbours, and are completely free-standing within their plot.  They can be built up to the boundary line, but cannot share any wall structurally with a neighbour.  

Semi-detached

Semi-detached houses are one of a pair of houses, usually (but not always) a mirror image of one-another.  

Terraced 

Terraced houses are part of a chain of houses of 3 or more.  An end-of-terrace house is still a terraced house (not semi-detached).  In rare cases, it's possible for a semi-detached house to become a terraced house.  This can happen if one of the two houses decides to build an extension that connects to another neighbour, such as an infill garage or a side extension.  This can happen when both neighbours agree that the extension would be useful, and then build it.  In this case, the other halves of each pair of semi-detached houses is suddenly part of a connected run of 4 houses, making them terraced houses, whether they like it or not.  

What about 'link-detached' houses?  

Sadly, this is pure marketing spin from housing developers, who have invented the term to make their terraced houses more appealing.  They usually have garages between otherwise free-standing houses, and those garages use the walls of the houses to support their roofs - this makes them terraced houses.  There are clear benefits to this arrangement, such as better acoustic separation between homes and more efficient use of land. However, from a Planning perspective these houses are the same as traditional terraced homes.

What about flats?

Flats gain no permitted development rights for any type of extension, so a Planning application would always be needed to add extra space.  This is the case even when houses have been converted into flats - as soon as they are flats they lose their permitted development extension rights.

Any questions? Ask in the comments below.