Thermal Insulation

For engineers and maintenance teams working in industrial, manufacturing, and high-temperature environments, thermal insulation materials reduce heat transfer to protect equipment, control surface temperatures, and improve energy efficiency. RS New Zealand provides a broad range of heat insulation products including thermal insulation sheets, boards, bulk fibre, and rods and bars.

Our insulating sheets are also available across various materials, including calcium-magnesium silicate, non-ceramic millboard, mineral wool, and fibreglass. These materials also offer operating temperatures extending up to 1200°C.

How Thermal Insulation Works

Thermal insulation materials work by interrupting each of these pathways through low thermal conductivity:

• Conduction: Heat transfers through direct contact between solid molecules. Insulation addresses this using low-conductivity materials or by trapping air within a fibrous or porous structure.
• Convection: Heat transfers through the movement of air or gas. Dense insulation limits this by restricting fluid motion within its mass.
• Radiation: Heat carries as infrared energy between surfaces. Higher-density or reflective materials reduce this mode, particularly at elevated temperatures.

The choice of material type, thickness, and density determines how well a heat-resistant insulation performs across a given temperature range and application environment.

Types of Thermal Insulation

Insulating sheets are materials or a mix of materials supplied in rigid board form, or a roll of material that can be cut and shaped to a specific size to suit your application. Insulation sheet is supplied in various lengths, widths and thicknesses.

Thermal Insulating Boards and Sheets

• Rigid Boards: These thermal boards can be used to help insulate and be found inside cavity walls, ceilings and under floors.
• Sheets: Insulating sheets are used in a wide range of industrial applications. Thinner than it's board alternative, sheets are used for gasket fabrication, insulating inside furnaces, or insulating inside equipment and appliances.

Bulk Fibre

Bulk fibre insulation is a mass of fibres that are used as a general infill or packing material for roofs and walls for high-temperature applications such as kilns and furnaces. Bulk fibre insulation is similar in appearance to cotton wool.

Rods & Bars

Thermal insulation rods and bars are made up of a mixture of thermal cement blended with mineral clays and several fibre-based materials and then are fully cured.

Thermal Insulation Materials

The material composition of a thermal insulating sheet or board determines its suitability for a given temperature range, environment, and handling requirement:

• Calcium-Magnesium Silicate (AES Wool): Rated for continuous use up to 1200°C, this bio-soluble fibre material is excluded from carcinogenic classifications. As such, it’s a safer high-temp insulation choice for furnaces, kilns, and continuously operating industrial equipment.
• Non-Ceramic Millboard: This fibre-free insulating sheet is suited to high-temperature applications where PPE-free handling is preferred. It also offers low shrinkage and is easy to cut and machine.
• Mineral Wool: Made from molten basalt, recycled glass, or steel slag, mineral wool suits industrial furnace lining, foundry, and building cavity applications.
• Fibreglass: Woven from fine strands of silicon, glass powder, and glass fragments, fibreglass delivers reliable thermal performance across a broad range of applications. PPE must be worn when handling this material.
• Cellulose: Made from recycled paper and cardboard, this offers a compact, eco-friendly format with good fire resistance for building applications.

Features & Benefits of Heat Insulation

Top-quality thermal insulation materials are designed to perform reliably across demanding industrial and high-temperature environments. Their features and benefits include:

• Flame Retardancy: All RS PRO thermal insulation sheets are flame retardant, supporting passive fire protection and safe use in high-temperature enclosures and equipment.
• High-Temperature Performance: Calcium-magnesium silicate bulk fibre and sheets operate continuously up to 1150°C. They can withstand short-term exposure up to 1300°C.
• Thermal Shock Resistance: Rods, bars, and select sheet types are thermal shock resistant, maintaining structural integrity when subjected to rapid temperature changes in industrial processes.
• Low Thermal Conductivity: The RS PRO range offers thermal conductivity as low as 0.04 W/mK, providing efficient heat containment with minimal material thickness.
• Flexible Sheet Formats: Calcium-magnesium silicate and AES wool sheets are flexible and easily cut and shaped on site, reducing installation time and material waste.
• Fibre-Free Millboard: Non-ceramic millboard is free from harmful fibres including asbestos, allowing safe handling and machining without PPE requirements.
• Quality Assurance: Every RS PRO product is rigorously tested against demanding industry standards and only approved when exceptional quality is confirmed.

Choosing the Right Thermal Insulation

To match the right thermal insulation to your needs, consider these factors:

• Maximum Operating Temperature: Confirm the material's rated temperature ceiling exceeds your application's peak. For example, non-ceramic millboard suits applications up to 1000°C while calcium-magnesium silicate AES sheets handle continuous use up to 1150°C. For demands of up to 1200°C, opt for bulk fibre.
• Form Factor: Thermal insulation sheets and boards suit defined flat surfaces, heat shields, and gasket fabrication. For cavity infill and furnace or kiln packing, choose bulk fibre. Rods and bars suit structural heat transfer and high-temperature support applications.
• Material Safety: Where PPE-free handling is required, fibre-free non-ceramic millboard is the appropriate choice. AES wool is bio-soluble and excluded from carcinogenic classifications under EU Directive 97/69/EC.
• Flexibility vs Rigidity: Flexible AES wool rolls suit curved surfaces and on-site cutting. Rigid boards suit fixed installation where structural support is needed.
• Thickness and Conductivity: Specify insulation against thermal conductivity in W/m·K rather than thickness alone. A thinner material with lower conductivity can outperform a thicker material with higher conductivity at the same operating temperature.

Applications of Thermal Insulation

Thermal insulation is often used alongside complementary seals, gaskets and thermal insulating films. Its common applications include:

• Industrial Furnaces and Kilns: Bulk fibre lining and insulating sheets maintain high processing temperatures while protecting structural components in ceramic, metal, and glass production facilities.
• Boilers and Heat Exchangers: Insulation reduces heat loss and improves energy efficiency in boiler systems and heat transfer equipment across industrial plants.
• Gasket Fabrication and Expansion Joints: Flexible AES wool sheets and calcium-magnesium silicate heat insulation sheet materials are cut on site for gaskets, expansion joints, and thermal breaks in pipework and flanged connections.
• Heat Shields in Automotive and Manufacturing: Insulating sheets are used as heat-resistant materials in engine bays, exhaust systems, and manufacturing machinery where component protection from radiant heat is needed.
• Appliance and Oven Insulation: Thermal insulation sheets line domestic ovens, storage heaters, and commercial catering equipment to maintain operating temperatures and protect external surfaces.
• Electrical Enclosures: Thermal sheets support heat management in electrical enclosures where component temperatures must be controlled.
• HVAC and Building: Rigid boards insulate cavity walls, ceilings, and floors in commercial and residential building applications.

Browse Heat Insulation Sheets & Materials Online

RS New Zealand is a trusted supplier and distributor of thermal insulation materials, stocking a comprehensive range of heat insulation sheets, boards, bulk fibre, and rods and bars from reliable brands including RS PRO, Goodfellow, and Sindanyo H91. Whether you’re sourcing a high-temp insulation sheet for furnace lining, a fibre-free millboard for on-site fabrication, or bulk fibre for kiln packing, browse the full range online.

Ordering & Delivery Information for New Zealand

It’s easy to get thermal insulation materials from RS New Zealand. You can browse the full range online, add the products to your basket, or go straight to the basket and enter the RS stock number.

You can also contact our team on 0800 888 780 to complete your purchase. Make the most of your order by adding other products such as insulation foam tapes, safety gloves, and thermal sensors in a single transaction.

Order today and enjoy fast delivery across New Zealand. For full information on delivery services and fees, please refer to our Delivery page.