We would always advise that an application for a Lawful Development Certificate (LDC) is submitted to the local planning authority. Not only will it prove the proposed works are compliant with any conditions, but will be useful when you come to sell your property.
Even when you are applying for planning permission, permitted development rights can be an important consideration in assessing applications as the ‘fall back’ position. We have successfully argued for a more permissive planning approval than the planners might usually permit by referring to permitted development rights which would allow a larger but less attractive extension.
1. Single-Storey Rear Extensions (Class A)
Permitted development allows homeowners to add a single-storey rear extension to their property. In certain circumstances, homes that aren’t in Conservation Areas or other designated areas, larger extensions will be permitted subject to the ‘prior notification’ process with neighbours.
2. Two-Storey Rear Extensions (Class A)
Permitted development also permits two-storey rear extensions, subject to certain limitations. These rights are rarely used since they restrict the extension to a smaller footprint on the ground floor. Usually, it’s better to apply for planning permission and to demonstrate compliance with planning policies governing overlooking and overshadowing.
3. Side Extensions (Class A)
- Side extensions are allowed under permitted development.
- They must not be taller than the existing house, and they should be single-story.
- Extensions cannot be built forward of the front wall or principal elevation that fronts a highway.
4. Loft Conversions (Class B)
- Loft conversions, including dormer windows and roof alterations, are typically covered by permitted development.
- However, there are specific rules regarding the volume and design of the loft space.
- Dormer windows must be set back at least 20 centimeters from the eaves.
5. Roof Alterations (Class B)
- Changes to the roof, such as adding rooflights or skylights, are often allowed.
- The alteration should not project more than 150 millimeters from the existing roof plane.
- Materials used should match the existing roof covering.
6. Porches (Class A)
- Small porches are usually considered permitted development.
- They should not exceed 3 meters in height and must be within 2 meters of the property boundary.
7. Outbuildings (Class E)
- Permitted development often covers the construction of detached outbuildings like sheds, garages, and garden offices.
- There are restrictions on the size and height of these structures.
- They should not cover more than half of the garden area.
8. Additional storeys (Class AA)
Houses constructed between 1 July 1948 and 28 October 2018 and not in a Conservation A or other Article 2(3) land can double the number of storeys. This is a new right and not widely known about.
- Number of additional storeys:
- One storey can be added to a single storey house
- Two storeys can be added if the house has more than one storey.
- Height increases:
- The house cannot exceed 18 metres in total height
- Each added storey cannot add more than 3.5 metres to the total height
- If not detached (e.g. terrace or semi) the total height cannot be more than 3.5 metres higher than the next highest building that the house is attached to, adjoins, or is in the same row as.
- The additional storeys must be constructed on the principal part* of the house
- The additional storeys must not exceed 3 metres in height or the height of any existing storey in the principal part* of the house (measured internally from floor to ceiling)
- Engineering operations must only include works within the existing curtilage of the house to strengthen existing walls and foundations
- The materials used must be of a similar appearance to those used in the construction of the exterior of the current house
- Windows must not be placed in any wall or roof slope forming a side elevation of the house
Limitations and Important Considerations:
Permitted Development Rights are rarely straightforward. Here are some of the restrictions or conditions that have to be complied with.
- Design and Materials: While permitted development rights grant some flexibility, the design, materials, and appearance of the extension should still be in harmony with the existing property and its surroundings.
- Listed Buildings and Conservation Areas: Special restrictions may apply to listed buildings and properties in conservation areas. In such cases, it’s advisable to consult with the local planning authority.
- Rights of Way and Easements: Be aware of any rights of way or easements affecting your property, as these may impact the permitted development rights.
- Boundary Disputes: Ensure that your extension does not encroach upon neighboring properties or create boundary disputes.
- Conditions and Prior Approval: Even though a project may fall under permitted development, it might still require “prior approval” for specific aspects, such as impact on neighbors’ amenity, highways, or contamination risks.
- Change of Use: Permitted development rights do not apply to changes in property use (e.g., from residential to commercial), so separate permissions may be required.
- Building Regulations: While planning permission may not be needed, you must still comply with building regulations to ensure safety and structural integrity.
- Local Variations: Some local authorities have introduced Article 4 Directions that remove permitted development rights in certain areas. Check with your local planning authority for any such restrictions.
It’s important to remember that the specific rules for permitted development may vary depending on your location within the UK, and they can change over time. Always consult with your local planning authority or a planning professional to confirm the current regulations and seek advice regarding your specific project.