Expanded polystyrene cladding more commonly referred to as EPS cladding, is a type of cladding that is a combination of thermal performance, design flexibility, light weight and cost effective, making it a practical and popular choice for builders and developers working across a broad range of project types and building classifications.
What EPS Cladding Actually Is
EPS cladding is an external wall system built around an expanded polystyrene board that is mechanically fixed to the structural wall substrate. Once fixed, the board is reinforced with a fibreglass mesh embedded in a base coat render, followed by a decorative texture finish coat applied over the top. The result is a complete external wall system that provides both thermal insulation and a finished façade surface in a single installation scope.
The polystyrene board itself is a rigid, lightweight thermoplastic material with strong compressive strength and dimensional stability. It is manufactured in a range of thicknesses to suit different thermal performance requirements and substrate conditions, and can be shaped and cut on site to accommodate a wide range of building forms and architectural details.
Why It Is So Widely Specified
Thermal performance is a significant reason. As the requirements of the National Construction Code around energy efficiency have become more stringent, the ability of EPS cladding to contribute meaningfully to a building’s thermal envelope has made it an attractive specification choice. The insulation value of the polystyrene board reduces heat transfer through the external wall, contributing to lower energy loads and improved internal comfort.
Weight is another factor. EPS boards are significantly lighter than masonry and many other cladding alternatives, which reduces structural loads and simplifies the installation process.
Design flexibility is also a strength of the system. The finish is applied as a render and texture coating over the top of the board, the range of colours, textures and surface profiles available is as broad. EPS can also be moulded or cut in different shapes and styles to compliment the architectural character making it a prime choice.
Compliance Considerations
EPS cladding systems require careful attention when it comes to fire performance compliance. The polystyrene board is a combustible material and the suitability of any given EPS system for use on a particular building depends on the building classification, the number of storeys and the specific certification attached to the system being specified.
A number of EPS cladding systems used across Australian construction carry CodeMark certification and have been independently tested and assessed for compliance with the National Construction Code. Systems such as NRG Greenboard and Exsulite carry BAL ratings for use in bushfire prone areas, and their certification documentation outlines the specific conditions under which they can be used on different building types. Understanding the certification attached to the system being specified is essential before installation commences.
Installation and Quality
Like all external cladding systems, the performance of EPS cladding depends heavily on how it is installed. Correct fixing patterns, appropriate expansion and starter channels, screws and weatherproofing details, and adherence to manufacturer specifications all play a critical role in how the system performs over the long term.
The base coat and texture finish application also requires skill and experience to execute correctly. An uneven base coat or poorly applied texture finish will affect both the appearance and the durability of the completed system. Also installers must be aware of what base coat and finish texture is suitable for EPS substrates, one wrong coat of product can be a costly crack to rectify or reverse.
At Crowntex Australia, we install EPS cladding systems including NRG Greenboard and Exsulite across residential and commercial projects in Queensland, New South Wales and Victoria. Our teams work to manufacturer specifications and current National Construction Code requirements on every project. If you have a project coming up, contact our team to discuss your cladding requirements.