Champions of Best Practice
Designed for Life
Posted on 20 Feb 2023
Read Keyfix Managing Director, John Duffin’s latest blog on the importance of designing products to last the lifecycle of the building and why using an enduring Cavity Tray can guarantee you peace of mind.
“Although often overlooked, the importance of designing products to last the lifecycle of the building cannot be overstated. Brick clad buildings are meant to last for hundreds of years and this should be a key consideration when installing materials and components in a building’s brick façade. However, all too often cavity trays are installed that include tapes and mastics – materials which are not maintainable, repairable, or replaceable. Therefore, this practice of using products whose longevity does not compare with the lifespan of the building is contradictory. Here’s why using a cavity tray system that is designed to last for the life of the building is the solution that guarantees you peace of mind.
Tapes and mastics don’t last
Unfortunately, no-one can guarantee the performance of mastic or tape in 100 years’ time. However, we have ample proof of stainless steel’s excellent performance.
For example, look at the iconic Chrysler Building. Built in 1928 in New York City’s industrial and coastal environment, it still remains in pristine condition today due to its durable stainless steel composition. Likewise, Keyfix’s Non-Combustible Cavity Tray (NCCT) system is composed entirely of stainless steel with no tapes or mastics, and when positioned within a masonry wall would not be exposed to industrial conditions, therefore will last even longer than stainless steel buildings in harsh environments.
Why cavity trays should be designed to last
Although it may seem convenient to opt for a cavity tray that contains tapes or mastics, using a product that isn’t designed to last for the lifespan of the building comes with implications which are at best inconvenient.
Mastics and tapes are products which can deteriorate over time may require maintenance, whi could make buildings that use them susceptible to leaks, failures and other disasters. Opening up a wall of a building to replace or maintain a cavity tray which relies on tapes or mastics, causes disruption, incurs expenses, and also causes health and safety issues for building occupants.
For stakeholders that have invested in the building, this is costly and impractical. For homeowners, they are faced with the threat of water ingress (i.e. damp), which is not only dangerous, but incredibly costly to fix. As a result, investors also face the possibility of having to pay huge remediation costs.
Using cavity trays which include tapes and mastics may seem acceptable, but may eventually incur costs later on when the materials potentially deteriorate. A well-informed designer or contractor should avoid using tapes or mastics where they cannot be replaced or maintained within the brickwork façade of a building.
ESG plays a part
With sustainability a pressing issue, whether products support Environmental, Social and Governance (ESG) agendas is a concern for housebuilders. Investors will take on additional risk where they use materials that do not last the life span of the building and create the issues of health and safety, disruption, security and financial issues. Therefore, using long-lasting products are seen as risk-averse, and may appeal more to investors.
The stress-free solution: the Keyfix Non-Combustible Cavity Tray
When it came to the development of Keyfix’s Non-combustible Cavity Tray (NCCT) system, we held many industry conversations with leading architects and brickwork contractors and in conjunction with the BRE, BBA, NHBC and Premier Guarantee. These conversations identified a number of key concerns that needed to be addressed in order to meet and exceed the expectations of the above stakeholders as well as ADB fire regulations. Following this, we went on to develop and patent a unique system to offer the industry a solution that addresses the commonplace issues found with jointing, DPCs and cavity trays using tapes and mastics.
The Keyfix NCCT is manufactured using Class A1 Non-combustible Grade 304 austenitic stainless steel, making the Keyfix NCCT the most enduring, cost-effective and maintenance-free solution.
As mentioned, the unique design of the Keyfix NCCT means that it requires no sealants or mastics. The Keyfix NCCT is the only Cavity Tray of its type on the market with a mechanical dry seal at joints. This means that it is not only designed to last, but the patented ribbed joint overlap eliminates the use of any sealants at joints which also removes the possibility of installation errors caused by onsite conditions.
Additionally, the Keyfix NCCT with its Integral Stop Ends on each tray ensures water is trapped and channelled outwards via the Keyfix NCW (Non-combustible Weep). These Integral Stop Ends enable the stainless steel tray to be self-supporting across the cavity and therefore requiring no support from the internal structure. This avoids clashes with other components, eliminates any cold bridging and removes the risks associated with differential movement.
As well as being designed for low-maintenance, the Keyfix NCCT has also been designed for onsite simplicity, making it a truly hassle-free cavity tray solution. The modular system incorporates integral Stop Ends, Non-combustible Weeps, and prefabricated external and internal corner trays with ribbed joints to provide a watertight seal and bond/coursing adjustability. This also removes the need for onsite fabrication, saving the bricklayer’s valuable time.
To prevent health and safety issues, costly and disruptive maintenance and/or repairs associated with using tapes and mastics, housebuilders, architects and specifiers should select a cavity tray solution that is designed to last the lifespan of the building, such as the Keyfix Non-combustible Cavity Tray system.