Ceramic Fiber Bulk

Loose ceramic fiber bulk for filling, vacuum-formed shapes manufacturing, and custom insulation applications.

Form: Loose cotton / Bulk fiber
Temperature: 1100-1430℃
Fiber Diameter: 2-4 μm
Asbestos: 100% Non-Asbestos

Overview

✦ Excellent thermal insulation
✦ Low thermal conductivity
✦ Good thermal shock resistance
✦ Multiple temperature grades

Raw form of ceramic fiber produced through melting and fiberizing. Used as base material for manufacturing other ceramic fiber products and as loose-fill insulation for complex spaces and cavities.

What Is Ceramic Fiber Bulk (Loose Wool)?

Ceramic fiber bulk is the loose, un-bonded fibre form of ceramic fibre — the raw material for modules, vacuum-formed shapes and castable reinforcement, and a practical fill for cavities and complex voids.

Key Technical Specifications

Property	Value
Maximum service temperature	classification 1260°C; service up to 1100°C
Density	60–200 kg/m³ (loose, as packed)
Thermal conductivity	0.05–0.12 W/(m·K) (as loose fill)
Standard thickness	loose / chopped fibre
Standard dimensions	compressed bales or bags
Fire classification	Non-combustible (ceramic fibre, asbestos-free)
Composition	high-purity alumino-silicate (Al₂O₃ + SiO₂) blown fibre, no organic binder
Standards	ASTM C892, ASTM C1086, ISO 10635, EN 10964

Properties & Advantages

Conforms to irregular cavities and voids
Low thermal conductivity as a fill
Base material for modules and shapes
Reinforces castables and coatings
Asbestos-free, low shot content

Typical Applications

Cavity and complex-void filling
Feedstock for modules and special shapes
Castable and mortar reinforcement
Filtration and high-temp packing

Installation & Handling

Place loosely without over-compression to keep the insulating air fraction; for casting, blend the chopped fibre evenly into the matrix.

Standards & Compliance

Manufactured to ASTM C892, ASTM C1086, ISO 10635, EN 10964 and controlled under a documented quality system. Supplied by a manufacturer holding ISO 9001, CE and SGS certifications, exporting high-temperature insulation to 60+ countries since 1982.

Why Specify This Product

Combines stable high-temperature performance with straightforward on-site fabrication. The material is asbestos-free, chemically stable in neutral and oxidising atmospheres, and supplied with full technical data sheets to support specification and inspection. Supplied by a manufacturer holding ISO 9001, CE and SGS certifications, exporting high-temperature insulation to 60+ countries since 1982.

Manufacturer & Supplier

Rosetexwool is a ceramic fiber bulk (loose wool) manufacturer and supplier serving more than 60 countries since 1982. Every ceramic fiber bulk (loose wool) is produced under a documented quality system certified to ISO 9001, CE and SGS, with batch-level traceability from raw material to finished product.

What our manufacturing capability covers:

In-house melting, fibre-forming and finishing lines for consistent grade and density
Dimensional, density and thermal checks against ASTM C892, ASTM C1086, EN 10964
Asbestos-free, low-impurity formulations verified by incoming and outgoing inspection
Standard and custom sizes, OEM/ODM grades, and cut-to-size supply for project quantities

For quotations, lead times or technical data sheets, contact our team with your specification and target service temperature. Explore the ceramic fiber insulation hub for the full range, or read the ceramic fiber insulation buying guide for selection support.

Related Ceramic Fiber Products & Alternatives

ceramic fiber blanket — Needled refractory blanket rated 1100–1430 °C with very low thermal conductivity and the thermal shock resistance that rapid furnace cycling demands.

ceramic fiber board — Rigid refractory board to 1430 °C in several densities and grades, cuttable with ordinary tools and stable enough to hold tight tolerances in place.

calcium silicate pipe sections — Built for industrial steam and high-temperature process piping where the insulation has to survive thermal cycling and still be removable for inspection.

For the full ceramic fiber range, temperature grades and density options, see our ceramic fiber insulation guide.

For adjacent material options across temperature and application ranges, explore our rock wool insulation hub.

Part of the Ceramic Fiber product family.

Key features

✓ Excellent thermal insulation
✓ Low thermal conductivity
✓ Good thermal shock resistance
✓ Multiple temperature grades
✓ 100% inorganic, non-combustible
✓ Easy to pack irregular spaces

Typical applications

Raw material for vacuum-formed products
Loose fill furnace insulation
Expansion joint filling
Ceramic fiber textile manufacturing

Technical specs

Form: Loose cotton / Bulk fiber
Temperature: 1100-1430℃
Fiber Diameter: 2-4 μm
Asbestos: 100% Non-Asbestos

Last updated: September 19, 2026

Frequently asked

What temperature can ceramic fiber insulation withstand? +

Ceramic fiber insulation withstands temperatures from 1100°C to 1430°C, depending on the grade. Standard (ST) and High-Purity (HP) grades are rated for 1260°C, while High-Alumina (HA) handles 1360°C and Zirconia (HZ) reaches 1430°C. Always match the grade to your specific operating temperature.

What are the differences between COM, ST, HP, HA, and HZ grades? +

The grades differ mainly in alumina (Al₂O₃) content and temperature rating. COM (1100°C) is the economy grade. ST (1260°C) is the standard industrial grade. HP (1260°C) offers higher purity with lower shot content. HA (1360°C) has higher alumina for superior thermal stability. HZ (1430°C) contains zirconia for the highest temperature resistance.

Is ceramic fiber insulation safe? +

Yes. Our ceramic fiber products are 100% asbestos-free and manufactured to international safety standards. They are classified as non-carcinogenic under EU Directive 97/69/EC. We recommend standard PPE (gloves, dust mask) during handling, as with any fibrous insulation material.

How is ceramic fiber blanket installed? +

Ceramic fiber blanket can be cut to size with a utility knife and secured using high-temperature anchors, pins, or stud welding. For furnace linings, a layered installation is recommended. For pipe insulation, wrap and secure with stainless steel bands. Full installation guidance and technical support are provided with every order.

What are the typical applications for ceramic fiber products? +

Ceramic fiber is widely used in industrial furnaces, kilns, boilers, petrochemical heaters, power generation equipment, incinerators, and building fire protection systems. It is ideal for backup insulation, expansion joints, door seals, and high-temperature gaskets.

Still deciding? Send your specs — we'll quote within 24 hours.

Get pricing

Request a quote for Ceramic Fiber Bulk

Fill out the form below with your requirements — our team responds within one business day.