Kitchen-Diner Extension Layouts London: 6 Designs That Work

Why Kitchen-Diner Extensions Dominate London Projects

The kitchen-diner extension is the single most requested extension type in London. It transforms the way families live by replacing a small, dark kitchen at the back of the house with a bright, open space that combines cooking, eating, and living.

For Victorian and Edwardian terraces, which make up the majority of inner London housing stock, the typical layout of small separated rooms no longer suits modern life. A kitchen-diner extension opens the back of the house to the garden, floods the interior with natural light, and creates a single multifunctional space.

• Strongest ROI: Kitchen-diner extensions return 50-70% of costs in property value, more than any other extension type in London
• Most requested by buyers: Estate agents consistently rank open-plan kitchen-diners as the number one feature London buyers look for
• Transforms daily life: Cooking while supervising children, entertaining while preparing food, and working from the dining table with garden views

The layout you choose determines how well the space functions. Getting it wrong means wasted space, poor flow, and a kitchen that fights against you rather than working with you.

Layout 1: Galley Kitchen with Dining Zone

The galley layout places kitchen units along one or both walls of a narrow space, with the dining area at the far end near the garden doors. This is the natural layout for side return extensions on London terraces, where the extension fills the narrow alley between your house and the boundary wall.

At 3-4m wide, the galley layout creates an efficient cooking zone with everything within arm's reach. The dining table sits at the garden end, benefiting from natural light through bi-fold or sliding doors. A rooflight over the junction between old and new brings light into the deeper parts of the plan.

• Kitchen runs along the side return wall with tall units opposite on the party wall
• Dining table for 4-6 at the garden end with full-width glazing
• Minimum 900mm aisle between opposing runs, ideally 1,200mm for two people to pass

Layout 2: L-Shaped Kitchen with Island

The L-shaped layout wraps kitchen units around two walls, with a central island separating the cooking zone from the dining area. This is the most popular layout for London kitchen-diner extensions because it creates clearly defined zones while maintaining an open feel.

The island serves multiple purposes: additional worktop space, breakfast bar seating, storage below, and potentially a hob or sink. It becomes the social hub of the room where family and guests gather while food is being prepared.

• Island needs minimum 1,000mm clearance on all sides for comfortable circulation
• Dining table sits alongside the island or at the garden end
• If placing a hob on the island, budget £2,000-4,000 for downdraft or ceiling extraction

Layout 3: Linear Kitchen Facing the Garden

A single run of kitchen units along the back wall of the extension, with full-width glazing above and below for maximum garden views. The dining table sits parallel to the kitchen run, creating a simple but effective dual-zone layout.

This layout maximises the connection between kitchen and garden. Cooking becomes a pleasure when you can look out across your garden while preparing food. It works particularly well on narrow plots where there is not enough width for an L-shape or island.

• Kitchen worktop below window level with glazing above for garden views
• Tall units and pantry storage on the side wall to compensate for lack of wall units
• Consider a large format sliding door to blur the boundary between inside and out

Layout 4: U-Shaped Kitchen with Open Dining

Three walls of kitchen units create the most storage and worktop space of any layout. The open end faces into the dining and living area, keeping the cook connected to the rest of the room while having everything they need within reach.

This layout suits serious cooks who want maximum functionality. The work triangle (sink, hob, fridge) is naturally compact, reducing steps during food preparation. A peninsula at the open end can provide casual seating and a visual divider between kitchen and dining zones.

• Minimum 1,200mm between opposing runs for comfortable cooking with two people
• Corner units need careful planning (lazy Susans, pull-out systems) to avoid dead space
• Peninsula end works well as a breakfast bar with stools on the dining side

Layout 5: Kitchen Island as Room Divider

A large island does double duty as a breakfast bar and a zone separator between the kitchen and the living or dining area. Kitchen units line one or two walls, while the island anchors the centre of the room and defines the transition between zones without using walls.

This layout demands a generous footprint but creates the most sociable kitchen of all. The cook faces the living space while working at the island, making conversation and supervision natural. The dining table can be positioned as a separate zone beyond the island.

• Island should be at least 2,400mm long and 900mm deep for a hob and seating
• Budget for good extraction: downdraft units (£2,000-4,000) or ceiling-mounted hoods (£1,500-3,000)
• Services (water, waste, electrics) to the island must be planned before the slab is poured

Layout 6: Broken-Plan Design

Broken-plan uses partial walls, sliding screens, internal glazing, or level changes to define zones within an open space. It offers the best of both worlds: the open feel of a single room with the ability to close off the kitchen when needed.

This approach is increasingly popular with families who have experienced fully open-plan living and found that cooking smells, noise, and mess spreading across the whole space is a daily frustration. A half-height wall, a Crittall-style screen, or a pocket sliding door lets you contain the kitchen when needed while keeping the openness when you want it.

• Crittall-style glazed screens (£1,500-3,000 per panel) provide visual separation while allowing light through
• Pocket sliding doors disappear into the wall when open, creating a fully open plan
• A step change in floor level (150mm) can define zones without any physical barrier

Layout Comparison

Key Design Considerations

Whichever layout you choose, these design principles apply across the board and will make the difference between a kitchen that works beautifully and one that frustrates daily.

Cost Guide for Kitchen-Diner Extensions in London

The total cost comprises three main elements: the shell build (structure), the kitchen fit-out (units, worktops, appliances), and finishing (flooring, decoration, lighting).

Frequently Asked Questions

Summary

The right kitchen-diner layout depends on your extension size, property type, and how your family lives. For side returns, the galley layout is efficient and cost-effective. For larger extensions, the L-shape with island is the most popular and versatile choice. Families tired of fully open-plan living should consider the broken-plan approach.

Whatever layout you choose, invest time in getting the work triangle right, plan more sockets and storage than you think you need, and budget for quality extraction. A well-designed kitchen-diner extension will transform your daily life and deliver the strongest return on investment of any home improvement.