Building envelope fastening systems manufacturer EJOT has developed an all-stainless steel façade substructure system which can play an instrumental role in the delivery of higher performing, more sustainable and stronger rear ventilated or rainscreen facades.
EJOT CROSSFIX is a complete framing system, backed with a comprehensive European Technical Assessment (ETA) to independently confirm its performance, and it is compatible with all types of building substrates, insulation materials and cladding. It is supplied as a package including all the brackets, rails, anchors and fasteners required to assemble a robust sub-frame.
By utilising stainless steel and the optional ‘Powerkey’, which ensures the best possible load distribution between anchors, the system achieves significantly higher load-bearing capacities than other substructures. Its innovative design offers more than simply structural strength and stability, however. When the system is specified, enhanced performance and sustainability targets can be achieved that offer major benefits to the building as a whole.
Discover CROSSFIX at Zak World of Facades
Attendees at the Zak World of Facades event in Manchester in June will be able to find out more about the contribution that CROSSFIX could make to their façade projects. The EJOT UK team will be exhibiting to give architects and façade designers the opportunity to discuss the technical characteristics of the system and its design features in depth.
Despite being a relatively new inception, CROSSFIX has been used widely in façade projects globally. When it was first developed in 2021, the bracket which is central to its performance capabilities – the Konsole – won a coveted German Innovation Award, reflecting the potential it offered to raise the bar on façade performance and ease of installation. And, now with a five-year record of successful installations behind it, the system is delivering on its promise.
One of the major advantages offered by CROSSFIX is its stainless steel composition. The majority of façade substructure systems available in the UK are aluminium. And whilst aluminium has the advantage of being lightweight and easily recyclable, it does have a number of disadvantages versus stainless steel, particularly in respect of its strength, thermal conductivity and embodied carbon.
As a result, stainless steel substructures like CROSSFIX are better aligned with today’s building design goals, especially in respect of creating highly insulated walls and maximising façade durability.
Reduced thermal bridging + greater strength = less material use
Stainless steel’s low thermal conductivity compared to aluminium has far-reaching benefits in the construction of rear-ventilated facades. Each bracket in the substructure provides the potential for a thermal bridge to develop, transferring heat from within the building to the exterior and vice versa. So, by reducing the amount of heat that can transfer through the bracket, heat loss can be cut.
With stainless steel brackets, however, there is an added benefit resulting from the material’s increased strength. Compared to a substructure created using a standard aluminium system, fewer brackets are required for CROSSFIX – that means fewer structural connections from the building substrate to the outer sheet and a further reduction in thermal bridging.
Such is the effect of this thermal bridge reduction when using CROSSFIX, which has the added benefit of a polyamide thermal stop to further reduce heat transmission, is that the depth of insulation can actually be decreased in a façade without compromising U-values. That makes it possible to either achieve higher levels of thermal insulation without increasing the wall depth, or reduce the overall wall thickness to increase the amount of floor space within the building – a potentially significant commercial benefit for the building owners or occupiers.
By opting for a reduced wall thickness, resource-use can be cut because less insulation will be required. And with fewer brackets and rails to connect, substructure assembly time and cost can also be reduced.
All these efficiencies, plus the fact that stainless steel is easy to recover and recycle at the end of the façade’s lifespan, mean CROSSFIX is well-suited to projects where the client is seeking the highest degree of sustainability. Its compatibility for meeting demanding standards for lower carbon construction is demonstrated through the system’s environmental product declarations (EPDs).
This means CROSSFIX is suitable for projects being constructed in line with internationally recognised schemes such as BREEAM and LEED, as well as Passivhaus schemes through its certification in Germany.
Innovative design for vertical and horizontal rails
One of the most innovative aspects of CROSSFIX is that the Konsole bracket is engineered in a way that means it can be used with both vertical and horizontal rails. This provides a number of practical benefits compared with substructure brackets that can only accept a rail in one direction, including offering greater design flexibility.
By enabling both vertical and horizontal rails in a single bracket, designers and façade engineers have the freedom to match the rail orientation to the cladding format and optimise fixing locations for aesthetic joint alignment. It also makes adapting to complex geometries, façade setbacks and mixed cladding systems on the same building more straightforward, providing flexibility that can be especially useful on projects where façade materials may change late in the design process.
Another important benefit of this dual orientation is that CROSSFIX allows the most efficient load path to be chosen rather than redesigning the bracket layout or switching substructure systems. In addition, the brackets have greater tolerance compensation for uneven substrates and enable easier vertical and horizontal alignment on site for faster installation, cleaner façade lines and reduced need for shimming or rework.
Compatible with more demanding fire safety standards
CROSSFIX’s stainless steel composition is also ideally suited to construction’s new building safety regime, particularly in respect of its ability to withstand high temperatures. It offers useful long-term oxidation resistance at temperatures of more than 800 °C and has a starting melting point at temperatures no lower than 1375 °C. Importantly, stainless steel retains a high degree of mechanical strength durability at high temperatures – for example, at 700 °C the substructure retains 55% of its strength.
As a result, the system is classified with an A1 fire rating according to EN 13501-1, the highest possible classification for non-combustible materials, signifying that it does not contribute to the spread of fire. For this reason, CROSSFIX may be preferable to substructure systems manufactured from aluminium or hybrid materials including plastic.
What all these advantages help to demonstrate is the importance of choosing the right substructure for a rear ventilated or rainscreen façade. Specify a system like EJOT CROSSFIX and more ambitious goals in respect of the façade’s performance, whole life cost and sustainability may be much easier to achieve.
Find out more about CROSSFIX at www.ejot.co.uk/CROSSFIX.