In most cases you do not need planning permission to refurbish a flat in London. Internal works such as a new kitchen, new bathroom, redecoration and replacing services are not development under planning law and need no application. Planning permission is only triggered by a change of use, external alterations or, in some flats, extensions. But planning permission is not the only consent that matters: as a leaseholder you almost certainly need your freeholder's licence to alter, and building control sign-off applies separately. This guide untangles all three.
Planning permission, building regulations and a licence to alter are three different things
The single biggest source of confusion in flat refurbishment is treating three separate approvals as one. They are governed by different bodies, ask different questions, and apply at different times.
Planning permission is granted by your local borough planning department and is concerned with how a building looks and is used: its appearance from outside, its footprint and its use class. Most internal refurbishment never engages it.
Building regulations are about safety and performance: structure, fire, electrics, drainage, insulation and ventilation. They are policed by building control, either the council's team or an approved inspector, and they apply to specific works regardless of whether planning permission is needed.
A licence to alter is a private matter between you and your freeholder, set by the terms of your lease. It has nothing to do with the council at all. You can have full planning permission and building control sign-off and still be in breach of your lease if you skipped the freeholder's consent. We see leaseholders trip over this constantly, so treat the three as a checklist, not a single hurdle.
Internal works that usually need no planning permission
The good news for most flat owners is that the heart of a refurbishment is invisible to planning law. Replacing a kitchen, refitting one or more bathrooms, rewiring, replumbing, replastering, laying new flooring, fitting new internal doors and redecorating throughout are not development and need no planning application.
Even removing or repositioning internal non-structural partitions within your own demise is generally outside planning control, because nothing changes externally and the use stays residential. The same applies to a straightforward like-for-like reconfiguration of an existing bathroom or kitchen layout.
Where internal works do touch other regimes, it is building regulations, not planning, that they engage: removing a structural wall, altering drainage, or new electrical circuits all need building control attention, which is covered in our building regulations guide. But the planning department has no interest in the colour of your walls or the brand of your kitchen.
The practical takeaway is that the typical London flat refurbishment proceeds with no planning application whatsoever, which is why the freeholder's licence to alter, not the council, is usually the consent that controls your timeline.
When planning permission IS required
Planning permission re-enters the picture the moment a refurbishment reaches beyond the inside of your flat or changes how the property is used.
External alterations are the most common trigger: new or altered windows, replacing the front door on a street-facing elevation, satellite dishes, flues and vents on a principal elevation, air-conditioning condensers, or anything that changes the external appearance, especially in flats. Unlike houses, flats and maisonettes have very limited permitted development rights, so external changes that a house owner could make freely often need permission when you live in a flat.
Change of use is the second trigger. Converting a single flat into two units, creating a house in multiple occupation above certain thresholds, or running a business from the property can all require permission and sometimes a separate licence.
Structural extensions, such as a rear or side addition, or anything that increases the building's footprint or height, will generally need permission. And in conservation areas or for listed buildings, the threshold drops sharply, which we cover next.
The table below summarises the common dividing lines.
| Type of work | Planning permission? |
|---|---|
| New kitchen / bathroom (same position) | Usually not needed |
| Internal redecoration and rewiring | Not needed |
| Removing internal non-structural wall | Not needed (building regs may apply) |
| Replacing windows like-for-like (no conservation area) | Usually not needed |
| Altering street-facing windows or front door (flat) | Often needed |
| New flue, vent or AC unit on principal elevation | Usually needed |
| Extension increasing footprint | Usually needed |
| Splitting one flat into two | Needed (change of use) |
| Any external change in a conservation area | Usually needed |
| Internal alterations to a listed building | Listed building consent needed |
Conservation areas and Article 4 directions
Large swathes of inner London sit within conservation areas, and they change the rules for external work even where they would otherwise be permitted.
In a conservation area, the borough takes a much closer interest in anything visible from the street: windows, doors, roof materials, railings, render and front boundary treatments. Replacements that would be unremarkable elsewhere, such as a uPVC window or a non-matching front door, are typically refused, and you will be expected to match original styles and materials. Some external works that are normally permitted development are removed altogether.
Many conservation areas also carry an Article 4 direction, which strips out specified permitted development rights so that a planning application is needed for changes that would be free elsewhere, commonly window replacement, front door changes and roof alterations. Article 4 directions vary street by street, so the only safe approach is to check the borough's policy maps before committing to any external change.
None of this affects purely internal refurbishment in an unlisted flat. But if your project touches anything the street can see, assume conservation-area rules apply until the borough confirms otherwise, and budget for period-appropriate materials, which cost more than standard alternatives.
The licence to alter: your freeholder's consent
Here is the consent most leaseholders forget and the one that most often stops a refurbishment in its tracks. Almost every London flat is leasehold, and almost every lease requires the freeholder's written permission, a licence to alter, before you carry out structural changes, alter services, change flooring or do anything affecting the building fabric.
This is entirely separate from planning permission. The council can be wholly indifferent to your new bathroom while your lease still forbids you from moving a single pipe without consent. Read your lease: the relevant clauses usually sit under alterations and improvements, and they range from an absolute bar to a requirement for consent not to be unreasonably withheld.
The process typically costs £1,500–£5,000 once the freeholder's solicitor and surveyor fees are added to your own drawings, and it takes anywhere from four weeks to four months. Common consent triggers include moving walls, relocating kitchens or bathrooms, changing flooring (acoustic conditions are standard in mansion blocks), and any work to windows or services.
Skipping it is a genuine risk: freeholders can require unlicensed work to be undone, and an unconsented alteration surfaces during a future sale. Start the licence conversation before you appoint a builder, not after.
Building control sign-off: separate again
Even with planning permission cleared and the freeholder's licence in hand, a third approval applies to certain works: building control. This exists to confirm the work is safe and compliant with the Building Regulations, and it is independent of both the council's planning team and your freeholder.
In a flat refurbishment, building control commonly applies to removing or altering a load-bearing wall, new or altered drainage, replacing windows, adding insulation, electrical work in bathrooms or new circuits (Part P), and the waterproofing and ventilation of new wetrooms. Notifiable electrical work must either be done by a registered competent person who self-certifies, or notified to building control directly.
You apply either through a building notice for straightforward work or full plans for anything structural, and on completion you receive a completion certificate. That certificate matters far beyond the build: conveyancing solicitors ask for it when you sell, and its absence can stall a sale or force indemnity insurance.
Our surveyors map all three consents at the first visit, planning, licence to alter and building control, so nothing is discovered halfway through. For a project-specific assessment, call Apex London on 020 3962 0455.
A simple sequence for getting it right
Put the three consents in the right order and a flat refurbishment runs smoothly; get the order wrong and you pay for delays.
Start by reading your lease and opening the licence-to-alter conversation with your freeholder or managing agent, because this is usually the slowest step and the one entirely outside your control. While that runs, confirm with the borough whether any external element needs planning permission, paying particular attention to conservation-area status and Article 4 directions if anything is visible from the street.
Next, identify which works are notifiable to building control and decide whether to use a building notice or full plans, and whether your electrician and other trades will self-certify. Only once the licence is granted and any planning matters resolved should you sign a building contract and order long-lead items.
This sequence prevents the classic mistake: appointing a builder, starting demolition, and then discovering the freeholder will not consent to the new layout. A fortnight of planning saves months of grief, and a contractor who has navigated London leasehold blocks before will steer you through all three regimes as a matter of routine.
Frequently Asked Questions
Do I need planning permission to refurbish a flat in London?
Usually not. Internal works such as a new kitchen, bathroom, rewiring and redecoration are not development and need no planning permission. Permission is only required for external alterations, a change of use, or extensions, and the threshold drops in conservation areas and for listed buildings.
What is the difference between planning permission and a licence to alter?
Planning permission is granted by the council and governs external appearance and use. A licence to alter is your freeholder's private consent, set by your lease, for structural changes, service alterations and flooring. They are separate: you can need a licence to alter even when no planning permission is required at all.
How much does a licence to alter cost in London?
Typically £1,500–£5,000 in total, made up of the freeholder's legal and surveying fees (often £1,000–£3,000, paid by you) plus your own drawings and specifications. Allow four weeks to four months for consent, and start the process before appointing a builder.
Do I need permission to replace windows in a London flat?
Outside a conservation area, like-for-like window replacement in a flat is often permitted, but flats have limited permitted development rights, so street-facing changes may still need permission. In a conservation area or where an Article 4 direction applies, window replacement usually requires planning permission and must match the original style.
Does removing an internal wall need planning permission?
No, removing an internal non-structural wall within your own flat needs no planning permission. However, if the wall is load-bearing the work is notifiable to building control under the Building Regulations, and your lease will almost certainly require a licence to alter from the freeholder first.