Cropley Street

Double height glass extension in London with a walk-on glass floor and frameless internal glazing

Cropley Street is a traditional London terraced home transformed by a double height glass extension. The homeowners wanted additional living space and more natural light throughout the house, while preserving its appearance from the street.

IQ Glass provided a glazing package combining structural glass and slim framed sliding doors across the rear elevation. Inside, a walk-on glass floor, frameless staircase balustrades and internal picture windows allow daylight to pass between floors and rooms.

The extension opens towards the terraced garden, bringing outdoor views into both storeys and creating direct access from the ground-floor living space.

Products Used

Project Partners

Ana Goncalves

Location

London
Frameless structural glazing and sliding doors create double height rear extension
Frameless internal glass balustrades to staircase

Extending a terraced home without changing its street frontage

The architectural challenge was to increase usable space while improving the distribution of daylight through the existing house. Extending into the garden created room for the new accommodation, with the changes concentrated at the rear of the property.

A glazed rear façade brings light into both levels. Fixed structural glazing sits above the sliding doors, creating a consistent glazed elevation with minimal visual interruption between the opening and fixed elements.

The internal arrangement continues this approach. Transparent floor glazing, staircase balustrades and bedroom windows allow light entering the extension to reach adjoining spaces. Each element contributes to a connected interior while retaining the separate functions of the rooms and circulation areas.

Structural glazing and sliding doors connect the house with its garden

The rear elevation combines large areas of fixed structural glass with slim framed sliding glass doors.

At ground-floor level, the sliding doors open the living space onto the terraced garden. Their narrow profiles maintain clear views when closed and complement the frameless appearance of the fixed glazing above.

This combination gives the two-storey extension a coherent exterior design. The fixed panels bring daylight into the upper level, while the sliding doors provide garden access and an opening for natural ventilation.

Planting, timber tones and natural textures continue the relationship with the garden inside the house, where views through the glazing form part of the everyday living environment.

A walk-on glass floor carries daylight between storeys

An internal walk-on glass floor creates a transparent connection between the first floor and the ground-floor space below. The glazed floor allows light to pass vertically through the extension while maintaining a usable surface at the upper level.

Frameless glass balustrades continue along the staircase, providing guarding without introducing an opaque barrier through the interior.

The first-floor bedroom also benefits from frameless picture glazing wrapping around two sides of the room. These internal windows connect the bedroom visually with the extension and allow it to receive borrowed daylight through the newly glazed space.

Together, the floor, balustrades and internal windows extend the benefits of the rear façade beyond the rooms immediately beside it.

Internal toughened walk on glass floorlight
Slim sliding doors and frameless rooflight to modern open plan kitchen renovation

Performance considerations

Daylight distribution was central to the glazing design at Cropley Street. The rear façade admits light across two levels, while the internal glass floor and picture windows provide routes for that light to reach further into the home.

The glazing also performs several distinct practical functions. Sliding doors provide access and ventilation; fixed panels maintain enclosure and views; staircase balustrades provide guarding; and the glass floor accommodates pedestrian use while transmitting light.

For walk-on glazing, the glass specification must respond to the panel dimensions, span and anticipated loading. Laminated glass construction forms part of this structural design, with the glazing and its supports considered together.

The restrained framing keeps these different elements visually consistent, supporting the open character of the extension and maintaining sightlines between the interior and garden.

Technical details

  • Rear façade: structural glazing arranged across two storeys, with fixed upper-level glazing above the sliding doors.

  • Garden access: slim framed sliding glass doors integrated into the ground-floor rear elevation.

  • Internal glass floor: walk-on glazing between the first floor and ground floor, allowing light transmission and views between levels.

  • Staircase guarding: frameless internal glass balustrades maintaining visibility through the circulation space.

  • Bedroom glazing: frameless internal picture windows wrapping around two sides of the first-floor bedroom and connecting it visually with the extension.

Cropley Street demonstrates how a double height glass extension in London can improve light, space and garden access throughout a terraced home.

The glazed rear elevation establishes the connection with the outdoors, while the walk-on glass floor, staircase balustrades and internal bedroom glazing carry that openness through the interior. The result is an enlarged home with views between spaces and a stronger relationship with its garden, while the street-facing architecture remains unchanged.

Architects and homeowners planning a similar project can contact IQ Glass to discuss structural glass extensions, slim sliding doors, walk-on glass floors and frameless internal glazing.

Associated Products

Frameless Glass Balustrades

Frameless glass balustrades for internal and external projects to create a clear yet strong safety barrier.
luxury new build home with minimal glass facade

Slim Framed Sliding Glass Doors

Sliding doors with ultra-slim sightlines, offering only the highest levels of performance and durability.
Strip Rooflights

Strip Rooflight

Using structural glass to create long runs of glass, connected together with silicone joints.

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