10 Home Extensions that Don’t Require Permission from Planners
Home improvements and especially home extensions sound like a good idea. There is profit to be made and resale value to be gained from both. Until you go and think about all the hoops you have to jump through with building regulations and planning permissions. Then, they become a headache.
But, not all home extensions and improvements require permitting. Some fall under Permitted Developments. And today, we will get into just that.
Will I need planning permission? What building regulations should I be aware of?
These are all very common questions homeowners ask themselves when considering a home extension or a home improvement project. The good news is that there are still some plans you can go ahead with without having to deal with the hassle of obtaining planning permission. This way, you will add more value to your home and make a more profitable sale.
Adding Extra Floors
Issued in August 2020, The Town and Country Planning amendments to Order 2015 suddenly got everyone talking about ‘airspace development’
Based on their current provisions, the Permitted Development Regulations allow extensions of up to two stories on certain types of homes and buildings in an attempt to meet the growing demand for housing.
Building new homes on top of detached blocks of flats
Through the Town and Country Planning (Permitted Development and Miscellaneous Amendments) (England) (Coronavirus) Regulations 2020, which came into force on 1 August 2020, a new Class A was introduced into the GPD – ‘New dwellinghouses on detached blocks of flats’.
The regulations state that owners or developers are allowed to extend purpose-built blocks of flats upwards by adding up to two additional storeys. The block of flats must have an initial height of at least three storeys before the extension. In addition, the total height (including the additional storey or storeys) must be 30 metres.
Other restrictions include:
- buildings built before 1st July 1948, or after 5th March 2018;
- the additional storey(s) must be built only on the principal part of the building;
- the floor to ceiling height of any additional storey has to be less than 3 metres or no more than the floor to ceiling height of any of the existing storeys.
Building new homes on top of other types of buildings
Additional permitted development rights were granted through an amendment to the regulations above, which came into force on 31 August 2020. Four new permitted development rights classes were introduced – classes AA-AD. Each class consists of a different type of building.
Classes AA and AB regard the development of upwards extensions on top of detached buildings and terraced buildings that are used for commercial or mixed purposes. Height restrictions of at least three storeys before extension apply only for Class AA. For class AB the height before extension needs to be two storeys or more above ground level for a 2-level extension and one storey above ground level for a 1-level extension.
Classes AC and AD regard the development of new flats on top of terraced buildings and detached buildings that are used as single dwellinghouses. The height restrictions of class AB apply here as well. In addition, the right to add two more storeys does not apply if the building has already been enlarged compared to its original structure.
Conditions and Limitations
For each of the newly added classes, the following restrictions and limitations will apply:
- the only permitted extensions are flats;
- the building has to be built between 1 July 1948 and 5 March 2018;
- buildings in conservation areas or listed buildings are not included;
- engineering operations are allowed within the existing curtilage of the building for strengthening existing walls and foundations or installing services;
- developers need to provide a report to the local planning authority regarding the management of the construction before starting work;
- works cannot take longer than three years after receiving prior approval.
Spot Up-and-Coming Areas

Choosing to live in an up-and-coming area in London will have more than one benefit. The most important one is how much your property’s resale value will grow over time. It will also help you climb the property ladder by paying less for a property that others will soon be paying extra for in an area that will continue to rise in popularity.
Here is how you can tell which London areas may be on the rise:
- Are there any regeneration plans in progress in the area or in nearby areas?
- How popular are the areas you are researching with younger residents?
- Have property prices in the area been rising steadily for the past few years?
- Are there any announced local authority or private development projects like community centres or shopping centres?
- Are more and more new homes being built in the area?
- Are the neighbouring areas thriving?
- Are new transport links planned or in progress?
- Are there several good schools in the area?
- Are there any major new employment opportunities?
Interior Remodels
Interior works are usually considered Permitted Development. So, if the improvement works you’ve set out to do are only inside your home and do not modify or extend the overall footprint of the dwelling, you do not require planning permission.
However, if you carry out any structural or electrical works, you will still need to obtain approval from Building Regulations for such works.
Converting a Loft
Loft conversions are an increasingly popular home improvement project. They can increase the overall usable space of a home and make it more valuable. Depending on your particular circumstances, you could be able to make a loft conversion without planning permission. Permitted Development allows for up to 40 m3 for these extensions.
If your loft has no natural light and you need to add windows, you must be aware of certain limitations. First of all, if the building is included in an Area of Outstanding Natural Beauty or a Conservation Area, you won’t be able to add rooflights. If it’s not, you can add rooflights but only if they are not raised higher than the highest part of the existing roof.
Converting a Garage
If your garage is attached to your home, you are in luck. Permitted Development allows for such conversions because they do not extend the overall footprint of the dwelling. This means that you can covert that space and extend your livable area without planning permission.
However, if your garage isn’t attached to the house, you will need to apply for a change of use according to Building Regulations.
Single-Storey Extensions
Extension projects like a bigger kitchen or a conservatory are popular home improvements. The regulations that such single-storey extensions must comply with are:
- They cannot cover more than half the area of land around the original house
- Their height needs to be under that of the highest part of the existing roof
- Eaves need to be lower than 3 meters anywhere the extension comes within 2 metres of a boundary
- Any materials used in the process need to match those of the exterior of the existing house
- The height of rear extensions cannot exceed 4 meters
- They cannot extend more than 4 meters beyond the rear wall of the original house for detached houses or 3 metres for other types of houses
- You need to inform the relevant Local Planning Authority of the proposed work and get prior approval.
Two-Storey Extensions
There are certain situations in which you could add a two-storey extension without requiring planning permission. The regulations allow for extensions that do not:
- cover more than half the area of land around your home
- extend towards a road
- go over the original height of the building or have a height above 4 meters
- extend more than 6 m from the rear of the dwelling (for attached houses) or 8 m (for detached houses)
- have a width that exceeds half of the original one of the house.
Such extensions must use the same exterior materials as those existing on the original house and not include elements like a balcony or veranda.
Outbuildings
Permitted development allows you to build an outhouse if the total area it covers isn’t over 50% of the total land area around the home. Allowed outbuildings cannot extend past the principal elevation and have height restrictions. They cannot be higher than 4 m in case the roof is dual pitch and 3 m for other roofs. The height is also limited to 2.5 m if the outbuilding is within 2 m of any boundary.
Restrictions are also in place for the permitted use of outbuildings. While you won’t be able to use them as an extra bedroom, you will be able to set up a small office there.
Garden Decks and Swimming Pools
For garden decks, the rules are not so strict. All you have to do is plan the height right. It needs to be under 30 cm and not cover more than 50% of the yard and then you won’t need any planning permission. More details on any decking restrictions are available on planningportal.uk.
Swimming pools are allowed under Permitted Development if they do not exceed half of the yard’s surface.
Fences and Porches
You will need to comply with certain restrictions if you want to improve or change your fence. Or build one in case you don’t have it. Permitted Development allows the construction or improvement of gates and fences if they have a height of less than 1 m when they are adjacent to a highway or 2 m in any other case. However, you are not allowed to make any changes in case the building is listed.
For porches, limitations apply to their height (no more than 3 m) and their location (they cannot be located less than 2 m of any boundary adjacent to a highway).
Turning Two Properties into One
Combining two properties is better than moving when you are in need of more livable space. So, you may be considering converting two properties into one. In this case, you may be able to do the required works under Permitted Development, provided you meet the required criteria.
Check with your local authorities to see what specific regulations may apply.