Guidance on Membranes and Insulation for Steel Roofing, Wall Cladding and Framing

Practical guides to selecting and installing insulation and membranes when building with steel

Two new guidance documents developed through extensive industry collaboration led by BlueScope and published by the Australian Steel Institute (ASI), provide practical direction on the selection and installation of membrane and insulation products for use with steel roofing, wall cladding, and light-gauge steel framing.

The publications include:

The publications respond to growing industry confusion stemming from the expanding range of insulation and membrane products now available and the inconsistent terminology often used to describe them.

Together, they provide clear guidance to help designers, builders, and installers understand what the different products do, and how to select and install them correctly to support steel building performance.

As building performance requirements continue to evolve under the National Construction Code (NCC) – particularly in relation to energy efficiency, condensation and weather resistance – selecting and installing the right insulation and membranes has become increasingly important in delivering compliant, durable, and high-performing steel building systems. For practitioners working with steel roofing, wall cladding, and light-gauge steel framing, understanding how these materials function within the overall system is essential.

Industry guidance and why it matters

With a growing range of insulation and membrane products on the market, terminology and product claims can be inconsistent, making it difficult to determine the right product for a specific roof or wall system. In many cases, multiple terms have been used to describe similar or identical products, with interpretations varying across the industry.

Together, these documents provide practical guidance and outline:

Common insulation and membrane terminology
Product categories commonly used with steel roofing, cladding, and framing systems
The function of different insulation and membrane types, such as thermal, vapour, air and water control
How to select the right product based on performance requirements and system design
How membranes and insulation interact with building systems, regulations, and environmental conditions
Practical installation guidance for common steel roofing applications

BlueScope collaboration

BlueScope’s Building Applications team played a leading role in developing the documents with the ASI, engaging broadly with industry stakeholders to ensure the guidance reflects practical, compliant and widely accepted practice.

The industry engagement included consultation with rollformers, metal cladding installer associations, housing industry and membrane and insulation industry representatives. This collaboration helped align the guidance with NCC requirements, relevant Australian Standards, manufacturing considerations, and common application approaches, supporting a more consistent understanding across the supply chain from design through to installation.

Relevance for COLORBOND® steel and TRUECORE® steel

For projects using roofing and wall cladding made from COLORBOND® steel, or framing made from TRUECORE® steel, the guidance is directly relevant and complements established building practices. It supports effective steel building system performance across thermal performance, condensation management, and weather resistance, and includes considerations for construction in bushfire-prone areas, in alignment with the NCC.

Who should use these guides?

The resources are designed to support a wide range of industry professionals, including:

Designers and specifiers
Residential and low-rise builders
Roofing and cladding installers
Certifiers

Whether reviewing a design, preparing a specification, or installing on site, these guides (read in conjunction with relevant manufacturer installation literature) provide a valuable reference grounded in industry standards and good practice.

BlueScope is pleased to support the publication of these industry resources, reinforcing best practice across the steel building sector and helping the supply chain make informed decisions when selecting and installing insulation and membrane products.