Brick Slip Systems vs Mechanically Fixed Facades: What Architects Need to Know

Two systems, one look: very different engineering

Brick slip facades have been growing in specification across Australian commercial projects. But "brick slip" is increasingly used as a generic term that covers two fundamentally different fixing methods: adhesive-based systems and mechanically fixed systems. The difference matters significantly for specification, NCC compliance, structural performance, and long-term maintenance.

This guide is for architects and specifiers evaluating brick slip facade systems for commercial projects in Australia.

What is a brick slip system?

A brick slip is a thin brick facing (typically 20–25mm) used to achieve the appearance of full-depth brick without the weight or construction method of traditional brickwork. Brick slips are applied to a carrier system fixed to the building's structural substrate.

The carrier system is where adhesive and mechanically fixed systems diverge.

Adhesive brick slip systems

Adhesive systems bond brick slips to a backing panel (typically a fibre cement or composite panel) using mortar, adhesive, or grout. The panel is then fixed to the substrate.

These systems work well in protected environments and low-rise residential applications. In commercial applications, particularly above three storeys, adhesive systems raise questions that specifiers should address early:

• Thermal movement: Adhesive bonds can be stressed by differential thermal movement between the brick slip and the backing panel over time.
• Waterproofing: Grout joints in adhesive systems require ongoing maintenance to prevent water ingress behind the panel.
• NCC compliance: The fire performance of adhesive and backing materials requires careful review under NCC Volume One Section C for buildings above 3 storeys.

Mechanically fixed brick facade systems

Mechanically fixed systems attach each brick slip to a structural rail through a physical mechanical connection, with no adhesive required for the brick-to-rail bond. The rail is fixed to the substrate.

Nexbrick™ uses a dual-engagement steel rail system where 25mm real brick slips clip into the rail from two contact points. The mechanical connection carries the structural load of each brick slip independently, without relying on adhesive bond strength.

Key performance differences:

• Structural redundancy: Each brick is independently fixed. Adhesive bond failure does not affect adjacent bricks.
• Thermal movement: The rail system accommodates thermal movement through the mechanical connection rather than stressing an adhesive bond.
• Fire performance: Real brick (non-combustible) on a steel rail system. No combustible adhesive or backing materials in the facade assembly.
• Wind and seismic loads: Mechanically fixed systems can be engineered to specific wind and seismic load requirements, which is critical for high-rise and exposed sites.

NCC 2025 compliance

Under NCC 2025, facade systems on buildings above 3 storeys are subject to requirements covering fire resistance, structural connections, waterproofing, and energy efficiency. Mechanically fixed systems using real brick generally have a clearer compliance pathway for non-combustibility under Section C than adhesive systems with composite backing panels.

Nexbrick™ meets NCC 2025 requirements for mechanically fixed facade systems. Full compliance documentation is available on request. See the Nexbrick NCC compliance page for a summary.

Design freedom

Both system types can achieve flat wall applications. Mechanically fixed systems generally offer more flexibility for complex geometry: Nexbrick™ handles soffits, curved facades, complex corners, and custom angles in any brick orientation, capabilities that are difficult or impossible with adhesive panel systems.

Nexbrick™ is also supplier-agnostic: any 25mm brick slip from any supplier can be used in the system. Architects are not locked into a proprietary brick range.

Specifying the right system

For low-rise residential and interior applications, adhesive brick slip systems can be appropriate and cost-effective. For commercial projects above three storeys, or any project with complex geometry, exposed conditions, or strict NCC compliance requirements, a mechanically fixed system warrants specification consideration.

For technical specification support on Nexbrick™, including CAD details and NCC compliance documentation, contact Modular Masonry Group or view the full Nexbrick™ system specifications.