If you are thinking about extending, converting, or making significant changes to your home, understanding the planning system is essential. Many homeowners are pleasantly surprised to learn that a wide range of improvements can be carried out without needing to apply for planning permission, thanks to permitted development rights. However, getting it wrong can result in enforcement action and the requirement to undo completed work at your own expense.
What Are Permitted Development Rights?
Permitted development rights are a set of rules that allow homeowners to carry out certain building works without needing to submit a formal planning application. These rights are granted by the government and apply to most houses in England and Wales, though they are more restricted for flats, maisonettes, and properties in designated areas such as conservation areas, Areas of Outstanding Natural Beauty, and National Parks.
Under permitted development, you can build a single-storey rear extension up to 6 metres from the original rear wall of a detached house, or up to 8 metres if you go through the prior approval process known as the larger home extension scheme. For semi-detached and terraced houses, the limits are 3 metres and 6 metres respectively. The extension must not be higher than 4 metres, must not cover more than half the garden area, and must use materials of a similar appearance to the existing house.
Loft Conversions Under Permitted Development
Loft conversions are one of the most popular home improvements and many can be carried out under permitted development. You are allowed to add up to 40 cubic metres of additional roof space for terraced houses, or 50 cubic metres for detached and semi-detached houses. The work must not extend beyond the plane of the existing roof slope facing a highway, the materials must be similar in appearance, and any side-facing windows must be obscure-glazed and non-opening unless the opening is more than 1.7 metres above the floor. Dormer extensions to the front of the house are not permitted development.
When You Need Planning Permission
You will need to apply for full planning permission if your proposed work goes beyond permitted development limits. Common situations that require planning permission include front extensions or porches that exceed the permitted development size limits, two-storey side extensions that would extend beyond the side wall of the house, any work on a listed building which also requires separate listed building consent, work in a conservation area where permitted development rights have been restricted, and converting a single dwelling into multiple flats.
If a previous owner has already extended the property using permitted development rights, those rights may have been partially or fully used up. It is always worth checking with your local planning authority before starting any work. You can also apply for a Lawful Development Certificate, which provides formal confirmation that your proposed work is lawful and does not require planning permission. This can be valuable evidence when you come to sell the property.
How to Apply for Planning Permission
Planning applications in England and Wales are submitted through the Planning Portal, the government's online planning service. The standard application fee for a householder application is 206 pounds. You will need to submit detailed plans and drawings, a location plan, a site plan, and a completed application form. Many homeowners hire an architect or planning consultant to prepare the drawings and handle the application, which typically costs between 1,000 and 3,000 pounds depending on the complexity of the project.
Once submitted, the local planning authority has eight weeks to make a decision on a standard householder application. During this period, your neighbours will be notified and given the opportunity to comment. The planning officer will assess the application against local and national planning policies, considering factors such as the impact on neighbouring properties, the character of the area, and highway safety. You will receive a decision notice either granting permission, granting permission with conditions, or refusing the application. If your application is refused, you have the right to appeal to the Planning Inspectorate.
Building Regulations vs Planning Permission
It is important to understand that planning permission and building regulations are two entirely separate systems. Planning permission controls what you build and where, focusing on the visual impact and land use. Building regulations control how you build, focusing on structural safety, fire safety, energy efficiency, drainage, and accessibility. Most building work, including work that does not need planning permission, will still need to comply with building regulations.
For example, a rear extension built under permitted development does not need planning permission, but it does need to meet building regulations for foundations, structural integrity, insulation, ventilation, and drainage. Your builder or architect should arrange for building control inspections at key stages of the work, and you should receive a completion certificate when the work is finished. This certificate is an important document that you will need when you sell the property.
Practical Tips Before You Start
Before embarking on any significant building work, check your title deeds for restrictive covenants that might limit what you can do with the property. If you own a leasehold property, check your lease for clauses requiring the freeholder's consent for alterations. Speak to your neighbours informally before submitting a planning application, as early communication can prevent objections. Finally, ensure that any builder you use has adequate public liability insurance and provides a written contract detailing the scope of work, timescale, and payment terms.