If you’re thinking about renovating your home in London, there’s one phrase you’ll come across early—and often: planning permission. Whether you’re extending the kitchen, converting the loft, or building a garden studio, understanding the ins and outs of planning permission is essential. The last thing you want is to pour money into a project only to be told by the council to undo it.
This guide cuts through the jargon and tells you exactly what you need to know before you start knocking down walls.
What Is Planning Permission?
Planning permission is the formal approval you need from your local council to carry out certain types of building work. It’s essentially the council’s way of checking that your proposed changes are appropriate, safe, and in line with local development plans.
It also helps maintain a consistent and considered approach to urban development. Without it, every homeowner could make major structural or visual changes without regard for neighbours, infrastructure, or heritage. Planning permission ensures that new developments or modifications enhance the built environment, rather than disrupt it. It takes into account a wide range of factors including access, traffic, aesthetics, environmental impact, and local character.
In London, each borough has its own planning department, but all must follow national guidelines. So, while there are broad rules that apply across England, local policies can differ quite a bit depending on where you live—from Kensington to Croydon. For instance, a side extension that’s easily approved in a suburban area of outer London might face strict scrutiny in a conservation area in central London.
When you apply for planning permission, your council will assess your proposal against its Local Plan, which outlines strategic development goals and design standards. They’ll also consider any objections from neighbours or community groups. This process ensures your plans are not just structurally sound, but also socially and visually appropriate for the area.
It’s worth noting that unauthorised work—building something without the correct permission—can lead to enforcement action. This might mean having to undo the work at your own expense, which is both costly and stressful. So while it may seem like an administrative hurdle, securing planning permission is a key part of responsible home improvement in London.
When Do You Need Planning Permission?
Here’s the rule of thumb: if your renovation alters the external appearance or use of your property, you may need permission.
This includes changes that affect the volume, height, or footprint of the building, as well as alterations that might impact neighbouring properties or the streetscape. In general, the more visible or significant your planned works are, the more likely you’ll need formal approval.
Common projects that often require planning permission include:
• Rear and side extensions, especially if they’re more than a single storey
• Loft conversions that include dormer windows facing the road
• Basement excavations, particularly those that affect the structural integrity or involve external light wells
• Changing the use of a property (e.g. turning a house into flats or a shop into a residence)
• Building a garden office or studio, depending on its size, height, and proximity to boundaries
• Installing new windows or doors in conservation areas or listed buildings
Some seemingly minor works can also trigger the need for permission if the property is in a protected area or if you’ve already made previous changes. For example, cumulative developments—like adding a loft conversion on top of an existing extension—can push you over the limits of what’s allowed without consent.
What about internal renovations?
Good news: if you’re simply updating interiors—new kitchen, fresh bathroom, new flooring—you typically won’t need permission. But it’s not always black and white. If your property is listed or in a conservation area, even internal changes might be restricted. In listed buildings, you may need Listed Building Consent to move internal walls, alter fireplaces, or even change certain fixtures.
In some cases, internal works can also indirectly affect planning status. For example, converting a loft into a liveable room may not need planning permission if it stays within certain limits—but adding roof lights, dormers, or a staircase might. So, it’s essential to view your renovation project holistically and get professional advice when in doubt.
What Is Permitted Development?
Some work can be done without applying for planning permission, thanks to what’s known as Permitted Development Rights (PDRs). These are rights granted by the government which allow homeowners to carry out specific types of improvements or alterations without the need to go through the formal planning process. They’re essentially a time-saving shortcut—but only if your plans stay within the permitted limits.
PDRs apply to many common home improvement projects, making them especially useful if you’re looking to expand your space or upgrade your property without jumping through hoops. For example, single-storey rear extensions that fall within certain dimensions (typically up to 3 metres for terraced homes and 4 metres for detached ones) are often allowed. Likewise, loft conversions that don’t exceed a 40 or 50 cubic metre volume (depending on property type) and don’t significantly alter the roofline usually fall under permitted development.
You can also install solar panels, add roof lights, build a modest porch, or convert part of your home into an office space—again, assuming all size and placement criteria are met.
But here’s the thing—Permitted Development Rights are not one-size-fits-all. In London, they’re often restricted or removed altogether. If your home is in a conservation area, a national park, or an Article 4 direction zone, the local council may have withdrawn these rights to protect the character of the area. The same applies if your home is listed—in which case, you’ll likely need additional consent for even minor changes.
So before you go ahead with any building work, check with your local planning authority. They can confirm whether your project qualifies under permitted development or if you’ll need to apply for full planning permission. Assuming you’re covered can lead to costly mistakes.
How Do You Apply for Planning Permission?
If your project doesn’t fall within the scope of Permitted Development, you’ll need to go through the formal planning application process. While that might sound daunting, it’s a well-trodden path—and with the right preparation, it’s perfectly manageable.
The first step is to get your designs drawn up. These should be clear and accurate architectural plans that show what you’re proposing to do. This includes floor plans, elevation drawings, and any site plans that help set your property in context. It’s wise to work with a qualified architect or designer—they’ll ensure the drawings meet council requirements and help avoid unnecessary delays.
Next, you’ll need to complete the application via the Planning Portal, which is the national online system used across England. This is where you’ll upload your plans, answer questions about your proposal, and pay the application fee. For most household developments, the fee is currently £258, although this can vary depending on the scale and nature of the work.
Supporting documents may also be required. A Design and Access Statement is often necessary for more sensitive developments, especially if you’re working within a conservation area or on a listed building. Other reports—like flood risk assessments or tree surveys—might also be needed depending on your location and the specifics of your site.
Once your application is submitted, the council will begin its review. This usually takes eight weeks, although larger or more complex proposals can take up to thirteen weeks. During this time, your neighbours may be formally notified and given the chance to comment or object. Their feedback will be considered, alongside planning policies and design principles.
The council will assess factors such as how the development affects light, privacy, and appearance, as well as whether it aligns with the borough’s Local Plan. If your application is approved, you’ll receive a formal decision notice. If refused, you’ll be told why—and you’ll have the right to appeal or revise your plans accordingly.
What If You’re Rejected?
It’s not the end of the world. If your planning application is refused, it can feel disheartening, but there are still several paths forward—and in many cases, a refusal simply means a rethink rather than a complete halt.
You’ve got a few sensible options:
• Revise and resubmit your plans, taking on board the council’s feedback. The refusal notice will usually outline the key reasons your proposal was turned down—perhaps it was too bulky, didn’t respect the local character, or overlooked neighbour concerns. A revised application that addresses these points stands a much better chance of success.
• Appeal the decision through the Planning Inspectorate. This is a formal process where an independent inspector reviews your case. It can take a number of months and involves submitting detailed justification for why you believe the original decision was incorrect. While some appeals are successful, they’re time-consuming and not guaranteed—so weigh this option carefully.
• Seek pre-application advice before submitting again. Most London boroughs offer this service for a fee. You’ll get early feedback from planning officers, helping you shape your proposal into something more likely to gain approval.
In a city as complex as London, planning departments are under constant pressure. They’re balancing housing demands, heritage conservation, environmental targets, and community feedback—all at once. With that in mind, it’s essential that your application is not only well-presented but clearly aligned with local policies and guidelines.
It’s also worth considering professional help. An architect or planning consultant can make all the difference in interpreting a refusal, tweaking designs, and advising on next steps. They’ll know how to navigate the system, avoid common pitfalls, and communicate effectively with planning officers.
A rejection isn’t failure—it’s part of the process. Many successful projects were granted permission only after an initial setback, so don’t be afraid to regroup and try again.
Special Considerations for London Homes
1. Listed Buildings
If your property is listed, any changes—inside or out—may require Listed Building Consent. This is a separate process from planning permission.
Listed status is given to buildings of special architectural or historic interest, and even minor alterations can affect the character of the structure. You’ll need to demonstrate that your proposed changes preserve or enhance the building’s significance, and in some cases, you may be restricted from using certain materials or removing original features. Failure to obtain Listed Building Consent before starting work is a criminal offence, so it’s not something to take lightly.
2. Conservation Areas
London has over 1,000 conservation areas. Living in one means stricter controls on alterations, especially to windows, roofs, and front gardens.
The aim is to protect the overall look and historical character of these neighbourhoods, so even seemingly modest upgrades—like replacing sash windows or paving over a front garden—can be tightly regulated. You may also need permission to remove trees, install fences, or change the external colour scheme. It’s wise to check with the council before making any visible changes, no matter how minor they seem.
3. Flats and Maisonettes
Permitted Development rights don’t usually apply to flats or maisonettes. Most changes will need full planning permission.
Because these properties are part of a larger building or shared structure, any alterations can impact other occupants or the building’s overall integrity. Extensions, roof alterations, or converting loft space in a flat will almost always require formal approval. Even internal modifications—like moving walls or changing layouts—may need sign-off, particularly if they affect fire safety or shared services.
4. Neighbours
London homes are packed in close, so overlooking, noise, and loss of light are common reasons for objections. Good design and clear communication can help prevent disputes.
Planning officers will often consider how your proposal affects neighbours’ privacy and daylight, especially in built-up areas. Keeping neighbours informed of your plans early on can help ease tensions and reduce the likelihood of objections. It’s also worth designing with their perspective in mind—clever positioning of windows or setbacks can make a big difference in getting your application approved.
Do You Need a Planning Consultant or Architect?
You don’t have to hire a professional, but it’s often worth it—especially in London. With strict planning policies, varying borough rules, and complex site constraints, a qualified architect or planning consultant can save you time, money, and stress in the long run.
An architect or planning consultant can:
• Help navigate local planning policy, identifying potential red flags early and suggesting practical solutions
• Design a compliant scheme that meets your goals, balancing creativity with regulations
• Improve your chances of approval by presenting a well-justified and clearly laid out application
• Handle the paperwork and communication with the council, ensuring deadlines are met and queries are dealt with efficiently
They’ll also help you understand how far you can push your plans before triggering the need for permission. In some cases, minor design adjustments can keep your project within permitted development limits, avoiding the need for a full application altogether.
Professionals also bring valuable experience from working on similar projects across London, meaning they’re familiar with what each borough typically supports or refuses. Many can also coordinate with structural engineers, heritage officers, or party wall surveyors if your project requires it. So while there’s an upfront cost, the value they add can more than pay off in smoother approvals and better outcomes.
Planning Permission vs. Building Regulations
These are not the same thing. Even if you don’t need planning permission, you may still need Building Regulations approval to ensure the work is structurally sound, energy efficient, and safe for occupants.
Think of it this way:
• Planning permission is concerned with the external appearance of your property, how it fits in with the surrounding area, and how it may impact neighbours or the local environment.
• Building regulations, on the other hand, focus on technical performance—covering everything from structural stability and fire safety to insulation, ventilation, drainage, and accessibility.
You may need both for the same project, depending on the nature and scope of the work. For example, a small internal renovation may not require planning permission but still needs to comply with building regulations. Conversely, a minor change to the exterior in a conservation area might need planning approval but not trigger building control involvement.
Building control officers will often inspect the work at different stages to ensure compliance. If you fail to meet the standards, you may be required to make costly alterations. So while planning permission often gets the spotlight, don’t overlook the importance of building regulations—they’re essential for a safe, legal, and long-lasting renovation.
Final Thoughts
Planning permission in London can feel like a maze—but with a bit of preparation and the right advice, it doesn’t have to be a nightmare. Before lifting a hammer, take the time to check what’s required in your borough. Speak to your neighbours, consult professionals, and don’t cut corners.
The bottom line? A well-planned renovation not only keeps you legal—it also adds real value to your home.
If you’d like to discuss renovating your property, contact us at Eton Builders for a free consult.