What Are the Benefits of a Two-Piece Cavity Tray?


Designed in conjunction with the major steel framing system (SFS) manufacturers and leading insulation providers, G–Tray™ became the first A1 non-combustible cavity tray system available in the UK. Unsurprisingly, since being released to the market, it has become the number one specified solution in Great Britain.

What is a Two-Piece Cavity Tray?

One of the main benefits of using the ACS G–Tray™ is that it is a two-piece system. But what does that mean in practice?

Thermal Break

As a two-part system, G–Tray™ creates a natural break within the cavity, minimising the potential of a thermal bridge forming between the inner and outer leaves of a cavity wall. In comparison, single-piece alternatives allow heat to move freely from one side to the other.

But don’t take our word for it. The Building Research Establishment (BRE) independently modelled G-Tray™ and determined that our cavity tray system has a calculated ψ-value of 0.009W/mK. Needless to say, that’s much lower than other available cavity trays.

Differential Movement

The natural gap between the upper and lower parts of the G–Tray™ allows these separate components to move in different directions without undermining the system’s waterproofing function.

The top GT2 tray follows the vibrations, small movements, deflections, and thermal expansions of the main structure, whereas the bottom GT1 tray follows the brickwork behaviour. This negates the system failing over time due to the natural movement of the building or subsidence, as it is subjected to far less stress than single-piece options.


The G–Tray™ is also manufactured off-site, delivered in two consistent parts and supplied in manageable lengths. All this makes it a far easier system to transport, move and install – especially long-rolled alternatives.

System Adjustments

The G–Tray™ was designed to accommodate bi-directional movement. This allows for the system to be adjusted on-site, before final install, without compromising the product’s performance or function.

These alterations are easy to make. Lateral adjustments are made by either increasing or decreasing the overlap of the two components. While cavity adjustments of up to ±13mm are possible due to the G–Tray’s design.

As an A1 non-combustible cavity tray, G-Tray is fully compliant with regulations surrounding materials within cavities and the use of steel framing system (SFS). It is also suitable for use in buildings of any height and is fully warrantied and indemnified.

For more information on G-Tray™, please visit this link.

Further Reading



Article originally published on 28th January 2021