Interlocking Panel


Expression™ Interlocking panels take the art of wall cladding to new levels. With an enormous variety of shadow lines, panel reveal widths, and application possibilities, steel Expression™ Interlocking Panels deliver a world of wall cladding excellence.

You could say that steel Expression™ Interlocking panels offer the ultimate contemporary take on the traditional Australian timber weatherboards.

The interlocking grooved flange design with the recessed joint allows designers to play with vertical, horizontal, and diagonal layouts along with variable length and lateral curving applications.

Expression™ Interlocking panels deliver refined elegance and modern sophistication and yet exhibit a playful exuberance that designers and clients alike will love. This is a profile that both defies as well as embraces the Australian climate whilst reflecting a modern Australian landscape.


Expression™ Interlocking Panels are only suitable for wall cladding and facade applications including curved and non-vertical.

The possibilities of horizontal, vertical or diagonal layout plus variable panel widths and lengths and shadow sizes offer a world of creative inspiration.

A range of panel reveal widths and lengths provide the opportunity for interesting mosaic type wall designs.

It’s a great way to create intense contrasts with roof lines and other building materials such as stone, timber, and glass. A range of recessed joint shadow widths up to 25mm wide adds to the creative possibilities.

Standard panel widths include:

  • 200mm
  • 250mm
  • 300mm

Custom panel reveal widths are also available ranging from range from 185mm to 385mm. Standard panel lengths range from 0.5 metres up to 6 metres with 4 metres being the recommended.

Various options for material types and colour choices expands the architectural design possibilities of Expression™ Interlocking Panels.

Liberate your imaginative vision with Colorbond, Zincalume, zinc, copper, aluminium, and Corten weathered steel options.

And, of course, the inspired richness of the Colorbond colour range can add even more multi-hued layers to your next project.

Materials and sheet thicknesses include:

  • Colorbond - 0.55mm BMT COLORBOND® / COLORBOND® Ultra / COLORBOND® Metallic / COLORBOND® Matt and ZINCALUME® Steel
  • Copper - 0.7mm BMT Copper
  • Aluminium - 0.7mm BMT Aluminium
  • Corten - 0.55mm
  • Zinc - VM Zinc, Rhine Zinc, Jarden Zinc (1.0 mm BMT)
Rustic Interlocking panels


Expression™ Interlocking Panels boast an enormous feast of colours to enhance any creative vision.

Imagine the possibilities of simple colours such as copper and Zincalume, or the rich warmth of Corten weathered steel.

Add in the more subtle hues and exciting possibilities of the Colorbond range and you’ll begin to appreciate the truly extraordinary potential of Expression™ Interlocking Panels.

The Colorbond selection of 22 colours from earthy tones to marine inspired shades reflects the powerful forces that have shaped the Australian landscape and environment.

Youthful exuberance, contemporary sophistication, classical charm; Interlocking Panels can fulfil your design brief with exciting possibilities.

Whether you’re designing for residential and commercial projects you can be adventurous with a bold statement or blend in with the environment; the choice is yours.


Expression™ Interlocking Panels are suited to walling and facade applications, but non-vertical walls will require the installation of a waterproof membrane behind the ventilation gap.

Expression™ Interlocking panels can be installed over load bearing main structures such as concrete walls, masonry walls or steel and require a continuous ventilation gap.

Timber or metal battens are installed at right angles to the Expression™ Interlocking Panels and the panels are then fastened directly to the battens. Maximum batten spans are as follows:

Panel width Batten span
200mm 800mm
250mm 700mm
300mm 600mm

Expression™ Interlocking panels promise incredibly easy and fast installation for significant cost savings. Fasten the grooved female flange to the batten using the correct flat-top screws. Slide the male flange firmly into the groove for a superb watertight fit.

As for any steel product, you must identify any potential material compatibility issues and design around those. Align sheets precisely when installing. Incorrect alignment can cause possible tension issues with panel movement due to thermal contraction and expansion.


Expression™ Interlocking Panels offer more than clean lines and sharply defined good looks. As a superior cladding product Expression™ Interlocking Panels only require low-maintenance care throughout the life of the product.

The precision engineered recesses promote a natural self-cleaning action with heavy rain washing away most dirt and debris.

There may be a slight tendency for horizontally laid panels to collect more dust but cleaning is straightforward - simply washing down with water will usually be sufficient.

Some regular maintenance is essential for all steel cladding types. Remove leaf matter, dirt and other organic material build-up once or twice a year. If the building is surrounded by trees you may need to remove leaf material more often.

Organic matter can build up and block guttering and cause water to back up. Such pools of water can potentially seep into roof or wall cavities.

Dirt and organic material build-up also significantly increases the rate of corrosion as well as damages the paint finish.

You can expect Expression™ Interlocking Panels to maintain their sharp good looks and exceptional performance for many years with a minimal maintenance schedule.


No1. Architectural Panel Systems proudly use superior Australian-made steel as part of our range of materials for our Expression™ Interlocking Panel products.

Industry leading best practices and the latest hi-tech production equipment ensures you get the best steel products available in Australia.

No1 Architectural Panel Systems and Expression™ Interlocking Panels—you can’t separate a great team.


Haymarket - Interlocking Panel


All roof, architectural panels, and wall cladding types manufactured by No.1 Roofing & Building Supplies are tested and fully certified to the new AS 1562.1:2018 standard.

This gives you real peace of mind for your next building project.




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