The Limes, Jersey

Project overview

The Limes is a large-scale mixed-use development comprising refurbished and new-build residential accommodation alongside a specialist care facility. The project was delivered as a landmark regeneration scheme, combining modern construction methods with a strong architectural identity informed by the site’s historical context.

The development was designed and constructed using lightweight steel framing and required an external wall solution capable of delivering high levels of fire performance, thermal efficiency and architectural flexibility.

The challenge

The scale and complexity of the development presented a number of technical challenges:

• Use of lightweight steel frame construction across a large multi-storey building
• A requirement for a drained cavity solution compliant with new-build warranty requirements
• High fire performance standards suitable for multi-occupancy residential use
• A façade design incorporating multiple materials, colours and finishes
• Extensive façade detailing, including recessed openings, parapets and balconies

The façade system also needed to achieve very low U-values while maintaining durability and impact resistance.

The solution

A Wetherby cavity rail external wall insulation system was specified for the steel frame construction. The system incorporates a partially ventilated drainage cavity between the sheathing board and insulation, providing effective moisture management while maintaining strong thermal performance.

Non-combustible ROCKWOOL stone wool insulation was installed within the system, delivering both high thermal efficiency and an A1 fire classification in accordance with BS EN 13501-1.

The system was finished using a combination of real clay brick slips and silicone thin-coat render, allowing the façade to replicate traditional masonry while achieving the performance benefits of a modern lightweight construction.

Installation

The façade system was installed by Fox Contracts under the coordination of the main contractor. The use of Wetherby RagRails simplified installation while allowing precise control over cavity depth and façade alignment.

Due to the complexity of the building geometry, bespoke detailing was developed for areas such as splayed embrasures and parapet junctions. In locations where brick slips were not suitable, a render finish was specified to maintain both performance and visual clarity.

Close coordination between the façade contractor, system designer and roofing contractor ensured robust junction detailing and continuity of insulation across the entire building envelope.

Finishes and detailing

Brick slip finishes were used extensively across the façades to provide a robust, impact-resistant surface with the appearance of traditional masonry. Multiple brick colours were specified to articulate the building mass and reflect the architect’s design intent.

Rendered areas were finished using Wetherby Silicone 4S Render, selected for its durability, water resistance and suitability for installation across varying weather conditions. Four different render colours were used to define architectural zones and create visual rhythm across the elevations.

The result

The completed façade system delivered exceptional thermal performance, with external wall U-values ranging from approximately 0.10 to 0.16 W/(m²K), significantly exceeding typical regulatory requirements.

The project demonstrates how cavity rail external wall insulation systems can be successfully applied to large-scale steel frame developments, delivering high fire performance, excellent thermal efficiency and architectural flexibility.

Key facts

• System: Cavity rail external wall insulation
• Substrate: Lightweight steel frame
• Insulation: Non-combustible stone wool
• Finish: Brick slips and silicone render
• Fire performance: A1-rated system
• U-values achieved: Approximately 0.10–0.16 W/(m²K)