Structural Glazing

What is 'Up and Over' Glass?

Up and over glass extension

Up and Over Glass is a phrase used to describe glass designs that do just that; go 'up' and then 'over. 

These types of glass designs are typically created using structural glass due to the bespoke and 3D nature of the glass designs. 

Claremont Square glazed extension with 'up and over' glass

Up and over glass is most often used to create a contemporary roof glazing that connects with a vertical glass element. These glazed elements can be fixed for a fully frameless design or opening (such as a sliding or pivoting door) to create a more functional glass design. 

Where is 'up and over' glass used?

'Up and over' glass designs are used wherever this type of 3D shaped glass design is required. These glass designs are very popular in areas such as; 

The combination of vertical glass with horizontal glass allows these types of structural glass designs to be versatile and utilised across the architectural scope. 

What is the maximum size for an 'up and over' extension?

One of the most prominent advantages of up and over glass is it is often created from structural glass to create a frameless design. The advantage of structural glass designs is that they have little to no restriction on their maximum size. 

Therefore, when creating an up and over glass design with structural glass the answer is that the maximum size is unlimited. Insulated toughened glass is available in sizes up to 20m long to ensure that design flexibility is maintained.  

an up and over glass link to a cotswolds cottage

There are obvious implications for cost and access when using extremely large glass panels so the design can be engineered to suit the project.  The roof element of the ‘up and over’ glass will be governed by the same rules of thumb as normal structural glass roof designs.  

You might want to read the article ‘How can I Cost Engineer my Architectural Glazing Project?’ for more insight into ways that structural glass designs can be maximised whilst managing costs.  


What are the glass options for 'up and over' glazing?

Due to the bespoke nature of 'up and over' glass designs, almost any glass specification can be used. Typically, double glazing will be used to create an insulated glass design, however triple glazing or single glazing can also be used depending on the use of the space and performance required. 

Additional functionality can be found from the glass through coatings such as solar control coatings

three slim up and over windows to a rear extension

Electronic glass technologies can be integrated into the structural glass design with heated glass, privacy glass or electro chromic glass. 

There are also laminated glass options for additional functions such as acoustic dampening, strengthening interlayers, bird protection and more.  

Design ideas for 'up and over' glass

Eaves windows follow the structural form of the roof creating frameless ‘up and over’ glass using strengthening interlayers within the vertical glass to support the weight of the horizontal boxed rooflight glass.  

Oriel structural windows offer a great solution as a light filled internal seating area that brings in light from many angles and is a form of ‘up and over glass’ with glass to glass frameless connections.  

Strip rooflights are long runs of structural glass that can be connected to vertical structural glass to complete an ‘up and over’ design using silicone joints.  

Up and over Invisio glazing systems are bespoke to suit specific daylighting needs. This means that architects and designers can adapt the glazing to optimise the entry of natural light while addressing privacy concerns or excessive heat gain through the use of solar control glass options. 

How are 'up and over' glass structures fixed? 

The fixing design for up and over glass designs vary from project to project. 

For insulated glass designs, we would typically use our Invisio structural glazing fixing method to ensure that the glass fixing detail had a full thermal break and was full tested. More bespoke fixing solutions may be required for listed buildings or other historical applications. 

up and over glass link to a listed church


At IQ, we specify fixing solutions for loadings and structural requirements to suit the overall design often combining additional mechanical and chemical anchor fixings for 'up and over' glass. 

Roman Park House is a fine example of an up and over structural glass roof silicone bonded to the expansive elevations of glass creating an elegant focal point and majestic atrium from the sunken lounge right up to the first floor and over.


Great George Street had an all- glazed atrium installed by IQ Projects to enhance views out of the Bristol based offices whilst optimising light ingress throughout the expansive building.   

Equally, the glass elements can serve as a ‘window’ to a focal point like an exposed brick wall or simply framing picturesque views.


Can I incorporate opening elements into 'up and over' glass? 

For the most frameless design possible, up and over glass is often all fixed. This allows the design to be created with no frame and with glass to glass junctions at all joins. 

If you would like to include an opening element into the up and over glass design, this is possible but often requires the inclusion of frames or steel to support the opening. 

This narrow extension on Warwick Gardens was an 'up and over' glass design which included slim sliding doors in the vertical elements to form an up and over glass extension. A steel post was included above the slim sliding doors to create an opening in the structural glass. 


Energy Efficiency and Sustainability

The advantages of up and over glass go beyond aesthetics and natural light. When designed with energy efficiency in mind, IQ’s Invisio systems can contribute to sustainability goals. Modern glazing technologies allow for excellent thermal insulation, reducing heating and cooling costs, and making buildings more energy-efficient and adhere to Part L of Building Regulations. Furthermore, the abundant natural light they provide can help reduce the need for artificial lighting during the day, saving both energy and money. 

What Next? 

Up and over glass is likely to remain at the forefront of modern architectural design due to its thermal performance and elegance, transforming structures into bright, inviting, and memorable spaces. 


Contact our friendly team today to discuss your glass extension project!