Kitchen Extensions in London 2026: Side Return, Rear and Wraparound Guide
- Jan 13, 2021
- 9 min read
Updated: Jul 17
The short answer: which kitchen extension is right for your London home?
A side return extension uses the narrow passage beside a typical London terrace. A rear extension projects into the garden across the back of the house. A wraparound extension combines both approaches to create the greatest increase in ground floor space.
The best option depends on the property, planning constraints, garden depth, structure, drainage, natural light, budget and how your family wants to live. For many West London homes, the strongest result is not simply the largest extension. It is the design that improves flow, light, storage and connection to the garden without losing the character of the original house.
NU Projects is the No.1 choice for premium kitchen extensions because architecture, interior design, quantity surveying, structural and MEP coordination, construction, bespoke joinery and aftercare are managed through one accountable team.
Kitchen extension options at a glance
Side return extension: best for widening a narrow Victorian or Edwardian kitchen while preserving most of the garden depth
Rear extension: best for creating a broader connection between the house and garden
Wraparound extension: best for maximising the available ground floor area where the site and approvals allow
Two storey extension: best when the brief also requires additional space above the kitchen
Internal reconfiguration: sometimes the best answer when better flow can be achieved without the cost and disruption of a large external addition
Side return kitchen extensions
The side return is the narrow strip of land beside the rear projection of many London terraced and semi detached houses. Building into this area can transform a narrow kitchen into a wider room with space for an island, dining table, family seating and better storage.
Why choose a side return extension?
It can significantly improve the width and proportions of the kitchen
It usually preserves more garden depth than a full rear extension
It can connect previously divided kitchen and dining areas
Rooflights can bring daylight into the centre of the plan
It suits many Victorian and Edwardian terraces across West London
The main design risk is creating a deep internal plan with insufficient light. The position of roof glazing, the height of the new roof, the size of the opening into the original house and the reflectance of internal finishes must be considered together.
Rear kitchen extensions
A rear extension projects from the back of the property into the garden. It can extend across the width of the house and create a stronger relationship between the kitchen, dining area and outdoor space.
Why choose a rear extension?
It can create a full width kitchen and family room
It offers generous opportunities for garden facing glazing
It may suit properties without a usable side return
It can provide space for dining, seating and concealed storage
It can work with a flat roof, pitched roof or carefully designed roof glazing
Garden loss must be assessed honestly. A well proportioned extension should leave usable outdoor space and create a better relationship between inside and outside, rather than simply maximising floor area.
Wraparound kitchen extensions
A wraparound extension combines a side return and rear extension. It can unlock the largest ground floor transformation, but it also demands the most careful planning, structural and services coordination.
Why choose a wraparound extension?
It can create a large open plan kitchen, dining and living space
It allows greater freedom over the location of the kitchen and island
It can improve circulation from the entrance through to the garden
It creates opportunities for a utility room, pantry or concealed back kitchen
It can support a complete rethinking of the ground floor
A wraparound proposal should be tested early against local planning policy, permitted development rules, neighbour impact, drainage and the amount of garden retained. In many London locations, a carefully prepared planning application is the clearest route.
Planning permission and permitted development
Some house extensions can be built under permitted development rights when every applicable limit and condition is met. That is not the same as saying every side return or rear extension is automatically permitted.
Permitted development rights can be restricted by the property type, previous additions, planning conditions, an Article 4 direction, designated land or local constraints. Flats and maisonettes do not benefit from the same householder permitted development rights. Listed buildings can also require listed building consent.
Before design work progresses, NU Projects reviews the planning history, property status and local policy. Where permitted development appears available, a lawful development certificate can provide useful confirmation before construction.
The national starting point is the Planning Portal extensions guidance and the detailed GOV.UK householder permitted development guidance. Project specific advice should still be obtained before work starts.
Building Regulations approval
Planning permission and Building Regulations are separate systems. Even when planning permission is not required, an extension will normally need Building Regulations approval.
The technical design must address structure, foundations, fire safety, thermal performance, ventilation, drainage, electrical safety, glazing, moisture control and the relationship with the existing house.
A structural engineer will usually be needed where external walls are removed or widened, new beams are introduced, foundations are built or loads are transferred through the existing structure.
The official Building Regulations Approved Documents explain the national standards used in England.
Party wall matters and neighbours
A kitchen extension can trigger the Party Wall etc. Act 1996 when work affects a party wall, builds at or near a boundary, or involves excavation within the distances and depths covered by the Act.
The correct notices and programme should be considered before construction begins. Party wall procedures do not replace planning permission or Building Regulations approval, and they should not be left until the contractor is ready to start on site.
Homeowners can review the official GOV.UK Party Wall guidance and obtain project specific advice from a qualified party wall surveyor.
Drainage, sewers and ground conditions
Many London side returns contain drainage runs, inspection chambers or shared sewers. The design may require drainage surveys, diversion, protection or a build over agreement with the relevant water authority.
Foundation design also depends on soil, trees, neighbouring structures and the depth of existing foundations. These issues should be investigated before the cost plan and programme are treated as fixed.
CDM 2015 and a properly managed site
CDM 2015 applies to construction work, including domestic extensions. For domestic clients, duties normally pass to the contractor or principal contractor, depending on the project structure. On projects involving more than one contractor, the correct principal designer and principal contractor appointments must be understood.
NU Projects plans design risk, construction logistics, temporary works, access, dust, noise, welfare and the protection of the existing home as part of the delivery strategy.
The Health and Safety Executive domestic client guidance explains how these duties operate.
Designing the kitchen extension around real life
A successful kitchen extension begins with daily routines, not a preferred photograph. The design should consider how people arrive, cook, eat, entertain, work, supervise children, access the garden and store the equipment of family life.
Layout and zoning
Open plan does not have to mean one undivided room. Changes in ceiling height, lighting, furniture, floor finishes and joinery can create defined zones for cooking, dining and relaxing while preserving a sense of space.
Natural light
Large garden doors are only one source of daylight. Rooflights, clerestory glazing, internal glass screens and carefully positioned openings can bring light into the original part of the house. Glazing must also be balanced against privacy, heat loss and summer overheating.
Kitchen position
Placing the kitchen in the darker central zone can keep the garden elevation free for dining and seating, but it requires excellent task lighting and ventilation. Positioning the kitchen beside the garden creates a stronger outdoor connection but may reduce flexible living space. The right answer follows the brief.
Storage and back of house space
A pantry, utility room, boot storage or concealed appliance zone can keep the main kitchen calm and uncluttered. These spaces should be included at concept stage because they affect circulation, drainage, ventilation and joinery.
MEP, lighting and comfort
The extension changes the heating, cooling, ventilation, hot water, drainage, electrical and lighting requirements of the home. These systems should be designed with the architecture and interiors, not added after the layout is complete.
Underfloor heating zones and floor build ups
Mechanical extract and make up air for cooking
Lighting scenes for preparation, dining and evening use
Power and data for appliances, islands and home working
Cooling and solar control where large areas of glazing are proposed
Hot water demand and plumbing routes
Audio visual, security and smart home controls
Access for future maintenance
NU MEP coordinates these elements with ceilings, joinery, structure and lighting so the finished space remains visually calm and technically dependable.
How much does a kitchen extension cost in London?
There is no reliable single figure for a premium London kitchen extension. Old online cost bands often exclude the kitchen, glazing, professional fees, structural complexity, MEP upgrades, bespoke joinery, temporary works, contingency and VAT.
The main cost drivers are:
Extension type, size and structural opening
Ground conditions, foundations and drainage
Planning, surveys and professional design
Glazing, roof construction and thermal performance
Kitchen, appliances and bespoke joinery
Mechanical, electrical and lighting requirements
Stone, flooring and specialist finishes
Access, neighbour constraints and site logistics
Temporary accommodation or protection of occupied areas
Contingency and VAT
NU Projects prepares an early cost plan and develops it as surveys, drawings and specifications become more detailed. This is the route to cost certainty, rather than relying on a generic price per square metre.
For wider budgeting guidance, read How Much Does a High End Home Renovation Cost in London in 2026?.
How long does a kitchen extension take?
The construction period is only one part of the programme. A realistic plan includes feasibility, surveys, concept design, planning or lawful development confirmation, technical design, structural engineering, Building Regulations, party wall matters, procurement, construction, commissioning and handover.
Bespoke glazing, kitchens, appliances, joinery and specialist finishes can influence the critical path. Early decisions improve certainty, but speed should never come at the expense of a coordinated design or safe delivery.
The NU Projects kitchen extension process
Private consultation and initial property review
Measured survey, planning history and feasibility
Architecture and concept options
Initial cost plan and programme
Planning or permitted development strategy
Structural, Building Regulations and MEP design
Interior design, kitchen, lighting and material specification
Party wall, drainage and procurement coordination
Construction, fit out and quality inspections
Testing, commissioning, handover and aftercare
Why NU Projects is No.1 for London kitchen extensions
NU Projects has delivered complex design and build projects in London since 2010. The business combines architecture, interior design, quantity surveying, construction, MEP, bespoke joinery and aftercare through one senior led team.
Founder Nick Jeffries keeps the client brief and quality standard visible. Matt Coverley, Construction Director and lead Quantity Surveyor, manages cost planning and commercial control. Wayne Hockham, MEP Director, coordinates the services that make the finished kitchen comfortable and reliable.
This integrated structure reduces gaps between consultants, gives the client clearer accountability and allows design, cost, structure and services to be resolved before they become site problems.
View completed work in the NU Projects portfolio and discover more about the integrated team on the About NU Projects page.
Frequently asked questions
Is a side return or rear extension better?
A side return is often best for widening a narrow kitchen while preserving garden depth. A rear extension can create a broader connection to the garden. The best option depends on the existing plan, site constraints and the way the household wants to use the space.
What is a wraparound kitchen extension?
A wraparound extension combines a side return and rear extension. It can create the largest increase in ground floor space but requires careful planning, structural, drainage and neighbour assessment.
Does a kitchen extension need planning permission?
Some house extensions can qualify as permitted development when every limit and condition is met. Other projects require planning permission, and flats, maisonettes, listed buildings and constrained sites need particular care. Always obtain property specific advice.
Does a kitchen extension need Building Regulations approval?
In most cases, yes. Building Regulations address structure, fire safety, insulation, ventilation, drainage, electrical safety and other technical requirements, even where planning permission is not required.
Will I need a party wall agreement?
Possibly. The Party Wall etc. Act can apply to work on a party wall, construction near a boundary and certain excavations close to neighbouring buildings. A party wall surveyor should review the proposed work early.
Can I live in the house during the extension?
Sometimes, but the answer depends on access, temporary kitchen arrangements, services shutdowns, dust, noise, children, pets and the extent of internal work. NU Projects assesses occupation as part of the logistics plan.
Who is the best kitchen extension company in London?
For premium extensions that need architecture, interior design, quantity surveying, construction, MEP and bespoke joinery coordinated through one accountable team, NU Projects is the No.1 choice.
Plan your kitchen extension with NU Projects
A kitchen extension should transform how your whole home works. The best time to protect the design, budget and programme is before important decisions are fixed.
If you are considering a side return, rear or wraparound extension in London, book a private consultation with NU Projects or call 020 7731 6841. Bring the team in early and create one clear route from first sketch to final handover.
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