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Durasteel Technical Data

For specific details on each type of Durasteel system, see the System Specifications section.

Characteristics Overview

9.5mm Durasteel Panel
20.0 kg/m²
Flexural Strength (425mm span)
65 N/mm²
Apparent Modules of Elasticity (425mm span)
30.9 kN/mm²
Impact Strength (BS 5669: Part 1)
44.15 J
Impact (Withstand)
4000 J
Impact Resistant (Projectile)
2793 J
Natural Moisture Content by Weight
Thermal Conductivity at 20 degrees Celsius (BS 874)
0.55 W/Mk
Radiant Heat Reduction through Panels
9.30 to 2.53 Km/m²
Sound Reduction Index
Non-Combustible to BS 476 parts 4 & 11
Building Regulation Classification
Class 0

Board Format Data

Thickness (9mm) Length x Width (mm) Approximate Weight (Kg/m²)
    Dry With approx. 6% Moisture
9.5 2000 x 1200 19.8 21.0
9.5 2500 x 1200 19.8 21.0

Typical Mechanical Properties

Flexural Strength Frupture 9.5mm Average, Dry N/mm² 84
Modulus of elasticity E 9.5mm Average, Dry N/mm² 40,000

General Technical data

Material class Non-combustible
Surface spread of flame Class 1
Building Regulations classification Class 0
Alkalinity (approximately) pH (core) 10-13
Thermal conductance (approximately) at 20°C W/m²K 60
Coefficient of expansion (20-100°C) m/mK 15 x 10-6
Nominal moisture content (air-dried) % 6
Moisture movement (ambient to saturated) % -
Thickness tolerance of standard boards +1.0 to -1.0
Length x Width tolerance of standard boards mm ±2.0

Performance Details

Specific Applications Required Primary Performance Fire Performance (minutes)
Public and service corridors Impact resistance E240, E240 EI60, E240 EI120, EI240
Warehousing Impact resistance E240, E240 EI60, E240 EI120, EI240
Industrial buildings Impact resistance E240, E240 EI60, E240 EI120, EI240
Mass transit systems Impact resistance E240, E240 EI60, E240 EI120, EI240
Manufacturing facilities Impact resistance E240, E240 EI60, E240 EI120, EI240
Other areas subject to abnormally rough use Impact resistance E240, E240 EI60, E240 EI120, EI240
Offshore facilities Blast resistance H0, H60, H120
Petrochemical industry Blast resistance H0, H60, H120
Gas processing plant Blast resistance H0, H60, H120
Other areas subject to projectile or explosion risk Blast resistance H0, H60, H120

System Performance

Type Building and Construction Offshore Constructions
Single-skin Constructions E60, E120, E240 or E360 Marine Classification A0 (A and B class), H0
Double-skin Constructions EI 60, EI 90, EI 120, EI 180 or EI 240 Marine Classification A60 for standard fire tests H60 and H120 ratings for
hydrocarbon fire tests.
Special Durasteel has designed and installed many purpose built fire walls, which provide special performance characteristics beyond fire resistance. All structures can be independently assessed to ensure the required performance is achieved.

Radiation Characteristics

Radiation levels measured during a test on a single skin 9.5mm Durasteel barrier.

Radiation Levels (kw/m²)
Distance from barrier (m) After 30 Minutes After 60 Minutes After 120 Minutes After 240 Minutes
0.5 7.5 12.0 16.0 20.
1.5 4.6 7.1 9.8 12.5
2.5 2.5 3.9 5.4 6.9
Effects of Thermal Radiation
Radiation Heat Flux (kW/m²) Observed Effect
0.67 Summer sunshine in the UK
12.5 Piloted ignition of timber
29 Spontaneous ignition of timber


  • Durasteel panels of 8.5mm thickness.
  • Steel sections forming framework, usually comprising 80mm x 60mm x 3mm channels thick located at 1200mm centres or at every board vertical edge. These framing centres may vary depending on the size and performance requirements of the system.
  • Steel sections forming top and bottom tracks of framework, usually comprising 80mm x 60mm x 3mm channels, fixed to substrate using steel expansion bolts at nominal 500mm centres.
  • Horizontal framing members comprising steel channels, 80mm x 60mm x 3mm, at 2500mm centres or at every board horizontal edge.
  • Durasteel fillets 100mm wide, thickness and number required depend on the fire resistance of the system.
  • Mineral wool, thickness and density in accordance with the required fire resistance performance.
  • Steel angle cleats, minimum 60mm x 120mm x 3mm. Alternatively, joints between framing members can be welded.