Structural Glass Facades vs Curtain Walling
IQ’s complete guide to the main differences between structural glass facades and curtain walling solutions.
Structural glass Facades and Curtain walling solutions may seem similar by appearance, but the structural properties and specifications of these systems are very similar.
There are many façade systems available on the market, each varies greatly in terms of frame size, material, and design. Two glazing solutions that are most sought after are structural glass facades and curtain walling, these offer the opportunity to create large highly glazed elevations which can be seen on large commercial buildings.
But when it comes to specifying your glass elevation what is going to be the best solution for you and your project design? Here we explore the most identifiable differences between a structural glass façade and a glass elevation made with a slim framed façade system.
What is a Structural Glass Facade?
Structural glass facades are frameless glass facades that are designed individually for each project using structural glazing.
Structural glass can be used as a modern alternative to a traditional façade system and comes with fewer restrictions as well as a more minimal design. IQ has developed bespoke fixing details for structural glass to allow for entire elevations of glass with completely hidden frames and fixing details. This is achieved by a technique whereby the glass is stepped over each floor, creating a seamless finish.
The structural facade system is a more technologically advanced solution which was designed to create large elevations of glazing where glazing is at the forefront of the design; resulting in highly glazed elements with virtually no framing.
When considering structural glass there is great freedom with glass specification. You do not have to create glass units to a certain weight restriction or depth, you are free to include
entirely bespoke glass units into the façade with little consequence to the design details.
What is Curtain Walling?
In the simplest terms, curtain walling glazing solutions are non-load-bearing glazing which sits on the exterior and is typically attached to the building’s flooring solution. This glazing solution does not support any of the weight created by the building and therefore only needs to support its own weight. Curtain Walls can be seen on large, glazed elevations, especially on high rises, as this glazing solution is designed to resist air and water infiltration. Predominantly the specification of this glazing is designed on a project-specific basis allowing for the performance values and glass spec to work in accordance with the requirements of the project. Curtain walling systems consist of a lightweight aluminium frame which is fixed on top of the structure of the building, and then the glazing is fixed to this structure.
What Is the Difference Between Structural Glazing and Curtain Wall?
Due to the simplicity of both glazing systems, there is a common misconception that the two solutions are the same, there is multiple difference between the two solutions. Structural glass facades create much more opportunity to have creative interpretation with the design of your glass façade, whereas curtain walling is a lot more restrictive.
There are various differences between these two façade solutions, to see the main difference see below.
The key design element of structural glass is that there is no frame. The glass units are fixed to the building structure using channels or angles that are designed to be hidden, regardless of the design. This means that with IQ’s expertise and experience, a completely frameless aesthetic is achieved. In comparison, Curtain Walling works in the opposite way as the glazing solutions offer no weight-bearing attributes compared to structural glass facades by IQ. This solution is not designed to support roofing or flooring but instead protect against wind resistance transfer from the glazed surface to the building’s floor.
The fixing details of these two solutions are very different due to the weight-bearing amounts for both, curtain walling solutions are fixed on top of an aluminium framing which is connected to the fabric of the building whereas, structural glass facades are fixed using details which are personal to the building’s makeup; to provide structural support.
Structural glass facades have many design benefits but when it comes to bespoke or unusual glass façade designs it really outshines the alternative options. As there are no framing systems involved with the creation of a structural glass façade you can engineer a structural glass wall to any specification. This could include simple alterations like angled or shaped facades to more complex 3D structures. Some façade systems will allow some variation on the design for a more bespoke finish, this may include the ability to create shaped or angled glass installations. It is much easier to create bespoke designs using a structural glass installation as there are no limitations. The flexibility of structural glass facades creates further opportunities to achieve the desired design proposal, there are vast limitations with a curtain walling system due to the fact it does not have structural integrity.
As there are vast options available for facade solutions, with this in mind, costs can vary dramatically. If you are using very large glass units, specialist electrical glass finishes or many layers of glass the cost of the glass package will increase. However, when looking at a structural glass facade you should normally look to budget for at least £1000 per m2. The costs of a curtain walling system will change depending on the system you choose. As an example, the average cost of curtain walling starts at £750 per m2 and structural glazing is approx. £1000 per m2.
If you are interested in comparing a structural glass façade to a slim framed façade package for your project, contact the experts at IQ Glass who will be happy to answer any questions. You can call us on 01494 722 880 or email email@example.com.
Tontine street features a large structural glass façade which was specified to mimic the wave movement of the sea, this combination uses both curved and straight panes of structural glazing. The fixed structural glass façade made for the four-storey face were made up of flat and curved structural glass panels to create a ‘wave’ effect across the front of the building. The capabilities of a structural glass façade is a lot more flexible with sizing and opportunities to add bespoke elements.
Find out more about the high-specification glazing used in this project Get in touch with us to talk to the team about specifying modern glazing in a commercial project.