Content reviewed: 9 October 2026 · 9 min read · BathWright
The short answer
Replacing the fittings in an existing bathroom or kitchen does not normally need planning permission. That covers the great majority of the work we do: a new suite, new tiles, a walk-in shower where the bath was, a new kitchen in the same room. What does need attention is a short list of specific things, mostly to do with electrics, ventilation and drainage, and in flats the lease. None of them is a reason to put off a renovation. They are a reason to agree the scope properly before the strip-out, which is what the site visit is for.
This guide is about England and about homes in London. Scotland, Wales and Northern Ireland have their own rules.
Four different kinds of permission, and why people mix them up
Most of the confusion comes from treating four separate things as one. They are decided by different people, for different reasons, and having one does not give you the others.
| What | Who decides | When it applies to a bathroom or kitchen |
|---|---|---|
| Planning permission | The council's planning department | Rarely. Internal work does not need it. It comes in only for changes to the outside of the building, such as a new window, rooflight or vent through the wall, and even then often only in a conservation area or where an Article 4 direction applies. |
| Building Regulations | Building control (the council or an approved inspector), or a registered tradesperson who self-certifies | Sometimes, for specific parts of the work: notifiable electrics, ventilation, new drainage connections, structural changes, or a new bathroom in a room that was not one before. |
| Freeholder's consent | The freeholder or managing agent of a leasehold flat | Often, in flats, when the layout, the pipework or anything shared is changing. Usually in the form of a licence to alter. |
| Listed building consent | The council's conservation officer | Only in listed buildings, and then for work that affects the building's historic character, inside as well as out. |
Typical situations
Replacing an existing bathroom or kitchen in the same room
No planning permission. Building Regulations apply to parts of the work rather than to the refit as a whole: the Planning Portal's guidance is that refitting a kitchen or bathroom with new units and fittings does not generally need approval, although the drainage or electrical work within it may. In practice that means the electrics are done by a registered electrician who certifies them, the extractor is sized and ducted properly, and any new connection to the drains is made to the standard the regulations describe. You do not have to apply for anything yourself. See Planning Portal: kitchens and bathrooms.
A new bathroom in a room that was not one before
This is the case the regulations treat differently. A bathroom in a former bedroom, a new en-suite in the loft or a WC under the stairs is likely to need building control involvement, because ventilation, drainage, structure, electrical safety and fire safety all have to be checked for a room that was never designed for water. It is a normal part of such a project, planned at the start, and it is one of the reasons a relocated bathroom is priced and programmed as its own project rather than as a refit.
Opening a kitchen into the living room
Taking down a wall between a kitchen and the next room is building work in its own right. If the wall carries load, a structural engineer designs the beam and building control checks it. Even a non-load-bearing wall can change the fire escape route from upstairs, so the layout is checked against the regulations before it is agreed. This guide covers renovating the kitchen within its room; opening it up is a separate conversation.
A flat with a lease
The lease sets the terms. Like-for-like replacement is usually fine. Moving the WC, changing the floor build-up, running new pipework, touching the shared soil stack or ducting a new extractor through the outside wall are the kinds of change that commonly need the freeholder's written consent, often as a licence to alter. The managing agent typically asks for a drawing of the existing and proposed layout, a note of the route of the new services and the specification of the waterproofing and ventilation. Every building has its own version of the list; we identify what yours needs at the site visit, so consent is in place before the strip-out rather than chased during it. Planning permission and building control approval do not replace the freeholder's consent, and the freeholder's consent does not replace them.
A listed building
Listed building consent is about the building's special character, which can include the interior and features not individually mentioned in the listing. Replacing modern fittings in the same position usually does not need consent; removing an old fireplace, altering historic joinery or running new services through valuable fabric does. Pipes within floor and ceiling voids are generally acceptable where no major structural work is involved. The owner or their designer makes the application; we supply the description of the work and how it will be done. If you are not sure whether your home is listed, the council's online register or the Historic England map will tell you. See Historic England: listed building consent.
The specific things we take care of
Electrics
In England, electrical work that is notifiable to building control includes a new circuit, a replacement consumer unit, and additions or alterations to circuits in the zones around a bath or shower. Most repairs, replacements and alterations outside those zones are not notifiable. The usual route is an electrician registered with a competent person scheme, who certifies the work and, for notifiable jobs, notifies building control through the scheme. After the work you receive the certificate appropriate to what was done, an Electrical Installation Certificate for a new circuit or a Minor Works certificate for a smaller alteration, and for notifiable work the compliance certificate issued through the scheme. Keep them; they are asked for when a flat is sold. See Planning Portal: electrics.
Ventilation
A bathroom needs a way of removing moisture, with or without a window. Approved Document F gives 15 litres per second as the minimum for an intermittent extractor in a bathroom; in a kitchen it is 30 litres per second for a cooker hood next to the hob or 60 litres per second for an extractor elsewhere in the room. A recirculating hood does not count as extract. The air has to go outside by a proper route; connecting to a shared duct in a block is checked against what the duct is for and what the managing agent allows. The 2026 edition of Approved Document F has been published but takes effect on 24 March 2027; the figures above are from the edition in force now. See Approved Document F.
Gas
Moving or connecting a gas hob is work for a Gas Safe registered engineer qualified for that type of appliance. A hob without a flue does not carry the same notification duty as a boiler, so do not expect a single standard "gas certificate" for every job; the engineer provides the paperwork appropriate to the appliance. An induction hob is a reasonable alternative in many kitchens, after the electrician has confirmed the supply can take it.
Drainage
Replacing fittings on their existing connections is a different matter from a new connection to the soil stack, a rebuilt stack or any work on underground drains, which are assessed under the Building Regulations. In a block the stack is usually shared, so who owns it and what the managing agent requires is settled before any change. A new connection to the public sewer, including some indirect connections, can need the water company's consent; a new basin does not.
Hot water and temperature
The regulations cap the temperature of water delivered to a bath at 48°C in new homes. In an existing bathroom that is not a requirement for every replacement tap, but a thermostatic mixer at the bath or shower is sensible wherever children or older people use the room, and it is a choice worth making when the brassware is specified rather than afterwards.
The outside of the building
A bathroom renovation only becomes a planning matter when it changes the exterior: a new window or rooflight, a new extractor outlet through the facade, a flue. In much of West London, conservation area status and Article 4 directions restrict what can be done to the outside of a house without permission, and the rules for a flat are tighter than for a house. The first question is always whether an existing opening can be used. Where a new one is needed, the status of the individual address is checked with the council before the scope is agreed. See, for example, Ealing Council: Article 4 directions and RBKC: conservation area maps.
What we settle at the site visit, and who does what
At the visit we go through the scope against this list: is anything moving, is a circuit being added, how will the room be ventilated, is the stack being touched, is the property leasehold, is the building listed, does anything change outside. The answers decide what, if anything, needs a form, a certificate or a consent, and the written quotation records it. The division of labour is simple: tradespeople certify their own work, the owner or their designer makes any application to the freeholder or the conservation officer, and we provide the drawings, descriptions and specifications those applications need.
What to keep after the work
- Electrical certificates: the installation or minor works certificate and, for notifiable work, the compliance certificate from the electrician's scheme.
- Any building control completion certificate, where building control was involved.
- The freeholder's licence to alter or written consent, where one was needed.
- Listed building consent, where it applied.
- Product documentation and the care instructions handed over at the end of the project.
Solicitors ask for these when a flat is sold, and a complete set is the easiest way to show the work was done properly.
In one sentence
A straightforward replacement of a bathroom or kitchen does not normally need planning permission, and the parts that do need certifying or consent are known before the strip-out: the electrics, the ventilation, the drains, and in a leasehold or listed home the lease and the listing. We check the scope against that list at the site visit, so there is nothing to worry about once the work has started.
