StyroTherm^® XPS

High-Performance XPS Insulation for Foundations and Green Roofs

installing Foamex StyroTherm XPS Insulation Boards

Made from our Styroboard® XPS, StyroTherm® by Foamex is a premium extruded polystyrene (XPS) sheet insulation solution, engineered for long-term performance in construction and architectural applications. With its high compressive strength and closed-cell structure, StyroTherm® offers outstanding thermal performance and water resistance—ideal for slab insulation, edge detailing, and below-ground protection. Manufactured in Australia from high-quality XPS using a process free from ozone-depleting gases, StyroTherm® delivers stable, high R-values across a range of building types.

Whether insulating a concrete slab or designing a sustainable green roof with StyroRoof® – our specialised XPS board for rooftop applications – Foamex provides high-performance insulation with proven durability, moisture resistance, and environmental integrity. As part of our circular production model, StyroTherm® also incorporates up to 90% recycled polystyrene, helping builders meet sustainability goals without compromising on performance.

Benefits of Extruded Polystyrene
(XPS) Sheets

Superior compressive strength ideal for load-bearing and structural applications
Long-term retained R-values for consistent thermal efficiency
Closed-cell XPS structure makes it practically impervious to water
Lightweight and easy to handle, cut, shape or sand
Manufactured in Australia to meet all local building codes
Free from CFCs, HCFCs, and ozone-depleting substances
Suitable for under slab, slab edge, perimeter, wall and green roof insulation
Contains up to 90% recycled polystyrene as part of Foamex’s closed-loop system

StyroTherm^® Product Details

StyroTherm^® XPS Technical Summary

Thickness (mm)	R-Value	K-Value (λ)	Compressive Stress 2% (kPa)	Compressive Stress 10% (kPa)
30	0.94	0.031	>90	>250
40	1.29	0.031	>150	>350
50	1.55	0.033	>230	>350
60	1.82	0.033	>240	>350
75	2.15	0.034	>280	>350

XPS Sheet length is 2400mm x 600mm wide. Thermal test method – AS-4859.1 / ASTM C518; Compression test method – AS-2498.3 / ASTM D1621

Framework for Sustainability Guide

Explore how extruded polystyrene (XPS) insulation transforms building envelopes to meet today’s energy-efficiency and carbon-reduction targets. This guide reveals the science behind closed-cell XPS production, its superior long-term R-values, moisture resistance and compressive strength, and practical strategies for specifying XPS in slab edges, under-slab systems and green roofs. Learn how up to 90% recycled content and a closed-loop recycling model make XPS a truly sustainable choice—and why high-performance insulation is central to designing low-carbon, comfortable buildings.

Product Brochure

Technical Specifications

Material Safety Data

PRODUCT WARRANTY

Product Handling

CERTIFICATION

FAQ's

Frequently Asked Questions About XPS Sheets

What is extruded polystyrene (XPS) used for?

Styroboard® XPS is a high-performance insulation material made in Australia and used across a wide range of building applications. StyroTherm® is the flagship XPS product for under slab, edge, wall, and perimeter insulation—delivering long-term thermal performance, durability, and moisture resistance. For niche applications like green roofs, StyroRoof® offers the same reliable XPS performance, tailored for rooftop environments. Whether you’re insulating below ground or above it, Styroboard® XPS provides a trusted, compliant solution with strong sustainability credentials.

Can XPS be used underground or in wet conditions?

Yes. Thanks to its closed-cell structure, Foamex XPS is highly water-resistant and retains its R-value and dimensional stability even in damp or below-ground applications, such as under slabs, slab-edge and around retaining walls.

Is Foamex XPS recyclable?

Yes. Foamex XPS is 100% recyclable. In fact, the StyroTherm® range contains up to 90% recycled EPS, sourced from construction offcuts and post-consumer polystyrene packaging. Foamex also accepts clean offcuts from building sites through its take-back service.

How long does XPS insulation last?

With correct installation, XPS insulation lasts 50 years or more. It maintains its thermal performance, structural integrity, and moisture resistance throughout the building’s lifespan.

Where can I get StyroTherm® or StyroRoof®?

Contact your nearest Foamex branch for expert advice and supply. We can help determine the right Styroboard XPS product for your insulation requirements and recycling goals.

StyroTherm® XPS