Glass extension in Leicester

Slim sliding doors connected to structural glass walls

Three sets of slim framed sliding glass doors create the main openings between the extension and garden. The systems were configured with flush thresholds to support seamless access and reduce the visual distinction between the internal and external floor levels.

The sliding doors connect directly with structural glass walls, creating large glazed elevations with minimal interruptions. This resolves the requirement for wide garden openings while maintaining the transparent appearance of the glass box extension.

Fixed and automated rooflights for daylight and ventilation

An automated opening rooflight was specified to provide natural ventilation without introducing visually heavy opening mechanisms. Concealed actuators allow the rooflight to open while preserving the minimal appearance of the roof glazing.

Rectangular fixed structural rooflights were positioned intermittently within a recessed section of the roof, creating a lightwell effect across the extension. This combination of fixed and opening roof glazing brings daylight deeper into the interior while supporting controlled airflow through the highly glazed space.

Technical details

• Slim framed sliding doors: 21mm sightline; max tested sliding pane 8.5m² up to 4m high and 500kg; glass thickness 26–32mm; typical Uw >1.1 W/m²K; Air Class 4 / Driving Rain Class 7A / Wind Class C4/B5; sound insulation up to 39dB; PAS 24 security; three sets installed with flush thresholds
• Structural glass walls: thermally broken fixing system; 63mm profile depth; max glass thickness 41.5mm; expected Uw 1.1 W/m²K; minimum fixing setback 55mm; profile height 60mm; structure deflection allowance 5mm; connected with the sliding doors to form the glass box elevations
• Fixed structural rooflights: thermally broken fixing section; max glass thickness 37.5mm; expected Uw 1.2 W/m²K; 95mm profile height; 150mm minimum upstand; installed intermittently within a recessed roof section to create a lightwell effect
• Automated opening rooflight: opening roof glazing with concealed actuators; specified to provide high-level natural ventilation while maintaining a minimal roof profile
• Solar control glazing: specified across the rooflights and large glazed elevations to reduce solar heat gain and glare while maintaining natural daylight
• Aluminium casement windows: slim aluminium profiles coordinated with the wider glazing package to provide additional daylight and local ventilation

Architectural glazing for highly glazed rear extensions

Warren Hill demonstrates how sliding doors, structural glass walls, opening rooflights and solar control glazing can be coordinated as one architectural package.

This approach is suited to architects and specifiers designing highly glazed rear extensions where daylight, garden access, natural ventilation and solar performance must be considered together.

To discuss a similar glass extension in Leicester, contact IQ Glass Midlands for technical advice on structural glass walls, sliding door configurations, automated rooflights and performance glazing.