Highgate West Hill

A Double Height Glass Extension in Highgate for a Reimagined Victorian Home

Located on Highgate West Hill, this Victorian terraced house was renovated by Paul Archer Design to create an open, contemporary family home. Central to the redevelopment is a striking double height glass extension in Highgate, designed and installed by IQ Glass. The glass volume links the lower ground and upper ground floors, expands the sense of vertical space and maximises daylight penetration across both levels.

The extension forms a transparent architectural hinge between spaces, transforming the home’s relationship with its garden and enabling long sightlines from the front of the house through to the rear.

 

Products Used

Featured In

Swedish Architectural & Interiors Magazine Nya Rum - Jan 2013, Interior Design (Taiwan) - Jan/Feb 2014

Project Partners

Architect: Paul Archer Design.

Location

London

Extending a Vertically Stacked Victorian Layout

The clients sought a home that retained the loft‑like openness they enjoyed in their previous apartment while accommodating the needs of a growing family. Victorian terraced housing, however, is traditionally arranged in a series of stacked rooms with limited cross‑flow of light. The lower levels were particularly dark due to the elevated garden and deep existing floorplates.

The design team removed the rear wall of the house on two storeys and introduced a multi‑level glass volume to connect the levels visually and physically. Achieving sufficient daylight, maintaining privacy and ensuring structural performance across two floors were key technical challenges. The extension also needed to feel modern without disrupting the Victorian character of the upper storeys.

 

A Double Height Structural Glass Envelope

IQ Glass engineered a two-storey structural glass extension that creates a seamless connection between the lower ground dining space and the upper ground living room. The structure is formed from an up and over glass roof that begins as a vertical glazed façade, then transitions into a sloping glass roof plane before folding horizontally as a clear glass canopy that projects views upwards from the upper level.

The glass roof is supported by a bespoke internal glass beam made from three layers of 10 mm toughened laminated low iron glass. The beam is connected to the building on one side with a hidden clamp and supported by a glass fin on the other, ensuring a completely transparent structural aesthetic with no visible steelwork. The high-performance insulated glass specification ensures comfort across all seasons.

Below the structural glass roof, a thermally broken aluminium bifolding door acts as the main opening from the lower ground floor to the newly levelled garden terrace. The three pane Schuco system provides direct access to the outdoors and maintains coherence with the glazing above.

Frameless Glass Balcony and Floor for Vertical Light Transfer

To reinforce the sense of openness between levels, IQ Glass designed a frameless structural glass balcony internally on the upper ground floor. The balcony consists of a clear glass floor and frameless balustrade, creating a floating viewing platform above the lower living space. The glazed floor allows daylight from the double height extension to filter freely into the lower ground floor.

The balcony balustrade is formed from two layers of 12mm toughened laminated glass with an ionoplast interlayer for enhanced strength. The glass floor panel is made from three layers of 10mm toughened laminated glass and sits flush with the internal floor finish to maintain a minimal architectural aesthetic. Both elements are held in place with bespoke hidden fixings to keep the assembly fully frameless.

A Space Featured Internationally

The Highgate West Hill project has been widely recognised for its architectural clarity and inventive spatial reorganisation. Featuring in international design publications including Nya Rum (Sweden, Jan 2013) and Interior Design (Taiwan, Jan/Feb 2014), the project demonstrates how contemporary interventions can be sensitively integrated into historic houses.

The introduction of the double height glass extension significantly enhances the property’s long-term value by delivering a rare combination of volume, daylight and transparency within a compact urban footprint. The result is a home that now performs at the level expected of high-end Highgate residences.

Technical Snippet

  • Double height structural glass extension to the rear of the house, formed from an up and over glass roof and vertical façade.
  • Glass roof specification: 8 mm toughened outer pane, 18 mm argon gas cavity, 8.5 mm toughened laminated inner pane.
  • Structural support beam made from 3 x 10 mm toughened laminated low iron glass. Beam connected to the building via hidden clamp on one side and supported by a structural glass fin on the opposite side.
  • Thermally broken aluminium bifolding door at lower ground level in three panes, measuring 2.6 m tall and 3.1 m wide.
  • Vertical glass façade to the extension measuring 3.3 m wide with a vertical height of 1.7 m before the glass roof pitch begins.
  • Frameless structural glass balcony to upper level, spanning 3.2 m wide.
  • Glass balustrade formed from 2 x 12 mm toughened laminated glass with ionoplast interlayer.
  • Glass balcony floor formed from 3 x 10 mm toughened laminated glass.
  • All glass elements connected using bespoke hidden fixings to maintain a fully frameless aesthetic.

A Double Height Glass Extension in Highgate

For architects, developers or clients seeking to create a double height glass extension in Highgate, this project demonstrates how structural glass can unlock light, space and architectural drama within traditional urban homes. Highgate West Hill shows the transformative potential of contemporary glazing when thoughtfully integrated into historic fabric.

If you are embarking on a renovation, basement reconfiguration or extension in North London and require specialist glazing expertise, IQ Glass can provide early stage technical guidance, design development support and bespoke glazing solutions. Contact our team to discuss your project.

Associated Products

Aluminium Casement Doors

Aluminium casement doors are sturdy and low-maintenance, offering excellent energy efficiency and security. They come in a variety of designs and colors, and can enhance the appearance and value of any home or building.

Low Iron Glass

Low iron glass, also known as extra clear glass, is used in various applications where color neutrality and high light transmission are desired, such as solar panels, aquariums, and architectural glazing.
Glass extension to a grade II listed home - Yewtree House - IQ Glass

Glass Box Extensions

Combining glass technologies and techniques to create bespoke glass boxes and structures.

Frameless Glass Balustrades

Frameless glass balustrades for internal and external projects to create a clear yet strong safety barrier.

Glass Floor

Using structural glass to create walk on glass floor panels to all specifications.

Ultra Slim Bifold Doors

Ultra Slim Bifold Doors are ideal for creating seamless indoor/outdoor transitions, maximising natural light and ventilation, and creating an open, modern feel in homes, commercial buildings, and other spaces.

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