Product overview
Glass extensions create bright, frameless living spaces with structural glass walls, glass roofs and minimal visible support. Using the Invisio structural glazing system, Sieger can design and install glass box extensions that feel completely clear, open and connected to the surrounding garden or landscape.
By using strong laminated structural glass beams and fins, the entire extension can be created almost entirely from glass. Building connections are made using the thermally broken Invisio section, helping the extension maintain a frameless appearance while supporting strong insulation and tested performance.
Sieger Systems supplies and installs frameless glass extensions and structural glass systems across London, Buckinghamshire, Berkshire, Oxfordshire, Hertfordshire, Surrey, Bath, Bristol and Somerset.
Premium performance
Bespoke made to order
Designed & made in the UK
PRODUCT FEATURES
Product features
Frameless glass box design
Thermally broken Invisio system
Structural glass beams and fins
Tested performance
To learn more about additional features:
Technical performance
| System type | Frameless glass box extension using the Invisio structural glazing system |
| Profile depth | 63mm Invisio | 72mm Invisio+ |
| Maximum glass thickness | 41.5mm Invisio | 62mm Invisio+ |
| Thermal performance | Expected Uw from 1.1 W/m²K Invisio | 0.6 W/m²K Invisio+ |
| Tested scenario | SC7 / SC6 / SC5 / SC4 structural glass scenarios |
| Typical Uw value | 1.2 W/m²K* |
GLASS OPTIONS
| System type | Frameless glass box extension using the Invisio structural glazing system |
| Profile depth | 63mm Invisio | 72mm Invisio+ |
| Maximum glass thickness | 41.5mm Invisio | 62mm Invisio+ |
| Thermal performance | Expected Uw from 1.1 W/m²K Invisio | 0.6 W/m²K Invisio+ |
| Tested scenario | SC7 / SC6 / SC5 / SC4 structural glass scenarios |
| Typical Uw value | 1.2 W/m²K* |
