Envello siding gets an upgrade with Shadow Line+
After years in development, Envello now includes a fire-rated option: Shadow Line+.
Designed to replicate timber, Shadow Line+ keeps the authentic grain detail and natural variation that define the Envello range, while offering certified fire performance when installed in line with the guidance.
Blending a premium look with straightforward fitting and low maintenance, Shadow Line+ is built for projects where you want the warmth of timber styling with added reassurance on performance.
Thorough testing
Shadow Line+ uses the same core construction as the wider Envello range, with the addition of specially developed fire-retardant components, including a harder elastomer surface layer to increase fire resistance.
Our Shadow Line+ siding boards have been tested to ASTM E84 and have a flame spread index of less than 25. They are also certified for use in WUI zones when install in accordance with our installation guide, as per CalFire – link here.
For specifiers, that combination of test standard, accredited certification, and installation-led performance provides confidence when selecting Shadow Line+ for real-world applications.
Ease of installation
Like the rest of the Envello range, Shadow Line+ is designed to be quick, clean, and easy to fit. Boards lock together using a tongue-and-groove system to increase rigidity and speed up installation.
To support a complete finish, the Shadow Line+ system includes fire-rated accessories, such as reveal boards, corner profiles, and fixings. Where visible fixings are required, color-headed screws are available to match each siding color.
The harder surface layer also adds rigidity, allowing batten spacing up to 600 mm centres (project conditions and loading considerations still apply).
Durable and low maintenance
Shadow Line+ is 100% wood-free, so cut ends do not require sealing to prevent moisture ingress, and the boards do not warp or rot like timber. The profile geometry also helps manage water run-off, supporting clean lines and long-term appearance.
With no need for painting, staining, or sealing, it is an easy-care solution for exterior design that still demands a refined finish.
Wide design choice with Shadow Line+
Shadow Line+ expands design options with an additional color: Limed Oak. Popular in the Millboard decking range, it delivers the look of sun-drenched timber with a bright, modern feel.
With five color finishes and boards suitable for horizontal or vertical installation, Shadow Line+ makes it easy to achieve a range of aesthetics, from traditional and rustic to crisp and contemporary.
Learn more about Shadow Line+ and order free samples
Explore the Shadow Line+ range, review the installation guidance, and order free samples to see the grain detail and color variation in person.
