Expol Slab & Foundation Solutions
A concrete floor slab offers strength and long-term durability — but without proper insulation and design, it can leak valuable heat, lowering comfort and energy efficiency. Expol's slab insulation and structural floor solutions combine cutting-edge polystyrene technology, expert engineering and New Zealand-specific compliance to deliver foundations that perform.
Insulating your concrete slab is one of the most important decisions you can make in a new build — and it's the only part of the thermal envelope you can't upgrade later. Our EXPOL Modelling and Research Findings reveal that you can save up to $4,400 by optimising an insulation mix. This includes reducing roof insulation while increasing slab insulation — a more cost-effective thermal improvement that delivers performance where it matters most.
Standard Slab-on-Ground Floors
Under-Slab & Slab Edge Insulation
EXPOL's concrete slab insulation systems are manufactured to improve comfort, energy efficiency and long-term performance in residential and commercial buildings. By adding insulation beneath the slab, at the perimeter — or both — designers can achieve energy-efficient buildings.
EXPOL offers a full range of insulation products to suit varying load and performance requirements:
High-compressive EPS designed to support thermal and structural slab performance
High-density EPS, commonly used for heavier commercial loads
Cost-effective thermal performance for most residential floors
Graphite-infused EPS achieving superior R-value at reduced thickness
Lightweight, rigid insulation with superior strength and water resistance
High-Performance Retrofit Slab Edge Insulation
By combining the appropriate EXPOL products, specifiers can tailor insulation to the needs of each project.
Click here to view Masterspec document
Waffle Pod / Pod Floor Slabs
Engineered Efficiency with Thermal Benefits Built In
Pod floor systems continue to grow in popularity for their construction efficiency and reduced concrete usage. EXPOL Tuff Pods, manufactured with recycled content are lightweight, durable, moisture resistant and deliver thermal insulation for the life of the building.
Thermal performance of pod slabs can be elevated further by integrating additional EXPOL insulation where required:
High-compressive EPS designed to support thermal and structural slab performance
Edge insulation for perimeter thermal control
Lightweight, rigid insulation with superior strength and water resistance
This flexible approach enables designers to meet a variety of performance expectations — from standard residential builds through to developments requiring higher energy efficiency.
EXPOL also partners with MAXRaft where continuous insulation is required across the slab system.
High-Performance Slabs
Maximum Thermal Control from the Ground Up
For projects where enhanced thermal performance, long-term energy efficiency and year-round comfort are priorities, EXPOL manufactures and supplies insulation that encases the entire slab in insulation which provides superior thermal performance.
These systems create a continuous layer of insulation beneath and around the concrete slab, significantly reducing thermal transfer and stabilising indoor temperatures. EXPOL supplies a range of insulation products that enable high-performance slab outcomes:
High-compressive EPS designed to support thermal and structural slab performance
Graphite-infused EPS achieving superior R-value at reduced thickness
Lightweight, rigid insulation with superior strength and water resistance
High performance slab edge insulation system
High-Performance Retrofit Slab Edge Insulation
Concrete Floor Insulation - Product Range
Click a product below to view full technical details and installation information
ThermaSlab
EPS Expanded Polystyrene for residential applications
Platinum Board
Graphite infused EPS for premium performance
SLABX200
Expanded Polystyrene Board for high-load applications
EXPOL-X (XPS)
Extruded Polystyrene for maximum performance
Tuff Pods
Extremely strong EPS blocks for concrete slab floors
ThermaSlab Edge
Slab edge insulation for Building Code compliance
Insulation Requirements by Slab Type
Click on each section to view detailed R-value specification tables
Slab-On-Grade (3604)
Insulation Solutions with Expol SLABX200 & Edge Insulation
| Area to Perimeter Ratio | SLABX200 50mm Under Slab Insulation | SLABX200 85mm Under Slab Insulation | SLABX200 120mm Under Slab Insulation | SLABX200 150mm Under Slab Insulation | 50mm SLABX200 + Edge ThermaSlab Edge/MaxEdge R 1.0 Edge Insulation | 75mm SLABX200 + Edge ThermaSlab Edge/MaxEdge R 1.0 Edge Insulation | 100mm SLABX200 + Edge ThermaSlab Edge/MaxEdge R 1.0 Edge Insulation | 120mm SLABX200 + Edge ThermaSlab Edge/MaxEdge R 1.0 Edge Insulation |
|---|---|---|---|---|---|---|---|---|
| 1 | 0.9 | 1 | 1.1 | 1.2 | 1.23 | 1.39 | 1.50 | 1.65 |
| 1.2 | 1 | 1.1 | 1.2 | 1.3 | 1.37 | 1.50 | 1.69 | 1.84 |
| 1.4 | 1.1 | 1.2 | 1.3 | 1.4 | 1.50 | 1.63 | 1.88 | 2.03 |
Waffle Pod Raft Slab (Brick Veneer)
R-value specifications for brick veneer construction
| Area to Perimeter Ratio | 220mm or 300mm EXPOL "Tuff Pods" | with ThermaSlab Edge or MaxEdge | with 50mm SLABX200 Under Slab | with 75mm SLABX200 Under Slab | with 100mm SLABX200 Under Slab | with 120mm SLABX200 Under Slab | with 150mm SLABX200 Under Slab | 50mm SLABX200 + ThermaSlab Edge or MaxEdge | 75mm SLABX200 + ThermaSlab Edge or MaxEdge | 100mm SLABX200 + ThermaSlab Edge or MaxEdge |
|---|---|---|---|---|---|---|---|---|---|---|
| 1 | 1.01 | 1.23 | 1.29 | 1.33 | 1.37 | 1.40 | 1.33 | 1.39 | 1.43 | |
| 1.2 | 1.10 | 1.36 | 1.44 | 1.50 | 1.55 | 1.60 | 1.50 | 1.54 | 1.60 | |
| 1.4 | 1.20 | 1.50 | 1.59 | 1.67 | 1.73 | 1.80 | 1.65 | 1.69 | 1.77 |
Waffle Pod Raft Slab (Lightweight Cladding)
R-value specifications for lightweight cladding construction
| Area to Perimeter Ratio | 220mm or 300mm EXPOL "Tuff Pods" | with ThermaSlab Edge or MaxEdge | with 50mm SLABX200 Under Slab | with 75mm SLABX200 Under Slab | with 100mm SLABX200 Under Slab | 50mm SLABX200 + ThermaSlab Edge or MaxEdge | 75mm SLABX200 + ThermaSlab Edge or MaxEdge | 100mm SLABX200 + ThermaSlab Edge or MaxEdge |
|---|---|---|---|---|---|---|---|---|
| 1 | 0.80 | 1.00 | 0.93 | 0.96 | 0.99 | 1.69 | 1.78 | 1.86 |
| 1.2 | 0.85 | 1.10 | 1.05 | 1.09 | 1.12 | 1.84 | 1.94 | 2.02 |
| 1.4 | 0.90 | 1.20 | 1.17 | 1.22 | 1.26 | 1.99 | 2.10 | 2.19 |
Installation & System Components
The installation process of EXPOL concrete floor insulation is quick and easy. Simply butt the sheets together on top of the DPC (polythene). It is important that the polystyrene sheets are not placed under any footings or thickenings for load bearing walls unless SLABX200 has been specified, in this case it can go under footings and thickenings for load bearing walls as per the engineers design.
The sheets can be taped together however this is not absolutely necessary. Once the sheets have been laid, place the reinforcing mesh on top using the required mesh chairs. See our Masterspec document for further information.
Key Benefits
Why choose EXPOL Concrete Floor Insulation for your project
Thermal Protection
Up to 10% of building heat loss is through concrete slab
Moisture Resistance
EPS shows less than 1% water content after 30 years
Durability
Won't degrade over time, performance maintained for building life
Compressive Strength
Provides thermal insulation and structural strength
Tested to Perform
BRANZ-tested to deliver proven, high-performance slab insulation
FURTHER INFORMATION
MANUFACTURING STANDARD
All products and grades of Expanded Polystyrene supplied by EXPOL for concrete floors comply with manufacturing standard AS 1366 Part 3 1992.
Find EXPOL products on these specification platforms:
