Basement and Extension Scheme

A Semi-Detached six-bedroom, five-bathroom in London SW6 is reimagined through a bold yet sensitive architectural intervention. The project pairs a new basement level with a refined rear extension, forming a sequence of spaces that expand the home both vertically and longitudinally, while preserving the established character of this Fulham streetscape. The result is a home that navigates the demands of modern family life with clarity, elegance, and a quiet confidence.

A Subterranean World of Leisure and Retreat

The newly formed basement is conceived not as an afterthought, but as a carefully orchestrated layer of domestic life—one that balances immersive leisure with subtle moments of calm.

At its core lies a dedicated cinema room, a cocoon-like environment enveloped in acoustic panelling and controlled lighting. This is a space designed for atmosphere: rich finishes, concealed AV infrastructure, and a sense of enclosure that heightens the cinematic experience. It offers a rare retreat within the home—one equally suited to family movie nights and social gatherings.

Adjacent to this, the basement’s wellness suite introduces a contrasting sensory experience. A timber-clad sauna with soft, integrated lighting anchors the space, accompanied by a cooling and shower area that completes the ritual. Ventilation is discreet but effective, protecting the integrity of the surrounding spaces while ensuring comfort and durability. Together, these rooms carve out an intimate subterranean sanctuary that elevates the home’s lifestyle offering beyond the expected.

Lightwells and carefully positioned glazing punctuate the basement, allowing daylight to penetrate deep into the plan. This interplay of controlled artificial light and selective natural light prevents the level from feeling isolated, instead giving it the sense of a quietly lit internal landscape.

Reframing the Ground Floor: A Modern Heart for a Family Home

Above, the rear extension transforms the ground floor into the home’s social core. Replacing a series of outdated additions, the new volume is deliberately restrained in form yet generous in its ambition.

The open-plan kitchen and dining area now unfolds as a continuous, light-filled space, amplified by full-height glazing that dissolves the boundary between inside and out. Minimal-frame sliding doors or pivot panels form a transparent façade to the garden, making natural light a defining material of the design. This spacious, contemporary arrangement finally gives the six-bedroom home the calibre of shared living space it deserves.

Rooflights or a clerestory strip draw daylight deeper into the plan, balancing the long footprint typical of these Victorian Semi-Detached Dwellings. The architectural language is understated: clean lines, muted tones, and finely detailed joinery that allows the volume to remain uncluttered and calm. The effect is one of effortless modernity—functional, elegant, and deeply connected to the rhythms of everyday family life.

Material Expression and External Presence

Externally, the extension adopts a quiet architectural posture. Using sympathetic brick or render tones and slim glazing profiles, the design complements the original townhouse without competing with it. The new volume reads as a light, careful addition that nestles into the garden rather than dominating it.

Soft landscaping mediates between the built form and the outdoors, creating a visual continuity that enhances the sense of openness from within the kitchen and dining spaces.

Engineering the Invisible

Beneath the architectural calm lies a rigorous structural and environmental strategy. The basement excavation relies on underpinning or contiguous piling, addressing both the urban context and neighbouring sensitivities common to London terrace infill projects. Waterproofing is delivered via a Type C cavity drain system, creating a dependable and maintainable line of defence.

High-performance glazing, improved insulation, and airtight detailing work in concert to enhance energy performance. Mechanical ventilation systems support air quality, particularly within the basement, ensuring that the new spaces achieve the comfort levels expected of a contemporary home.

A House Rebalanced

The transformation reshapes the experience of the home. Its six bedrooms and five bathrooms remain the core of the domestic accommodation, but the reworked lower levels provide the spatial quality and amenity necessary for a modern family lifestyle. The architecture expands the home not just in size but in possibility, redistributing spaces for leisure, gathering, cooking, and restorative retreat.

This is an urban house that now breathes, flows, and lives differently—anchored in its heritage but enriched through a quietly ambitious piece of contemporary design.