Fire-Rated Fiber Cement Board: E120, EI90, EW120 Tested Wall Systems

Why fire resistance classification matters in European construction

Under the EU Construction Products Regulation (CPR), load-bearing and separating elements in buildings must meet defined fire resistance requirements. Fiber cement board is increasingly used in fire-rated wall assemblies — but the board alone does not carry a fire rating. The rating belongs to the tested wall system.

Terasun TSM has been independently tested in a wall assembly configuration and achieves:

The tested wall assembly

The fire test was conducted on a wall system with the following configuration:

• Facing boards: Terasun TSM 12 mm, CE marked, EN 12467
• Frame: Steel stud or timber stud (per test documentation)
• Insulation: As specified in test report FIRES-CR-284-25-AUPE
• Fasteners: As specified in the test report

When specifying this system, the full assembly must replicate the tested configuration. Substituting components — including the board itself — invalidates the tested performance unless supported by field of application rules or additional testing.

Terasun TSM fire-rated wall assembly cross-section diagram

Fiber cement vs gypsum board for fire partitions

Both fiber cement and gypsum board can be used in fire-rated wall assemblies. The choice depends on the environment and performance requirements:

For escape corridors, stairwells, and fire compartments in humid or exterior-adjacent locations, fiber cement offers superior long-term performance because it does not absorb moisture and degrade over time.

Specifying fire-rated assemblies with TSM board

Step 1: Determine the required fire resistance

Consult the national building regulations for the country of construction and the project fire strategy. Common requirements:

• Residential buildings (≥4 storeys): REI 60–90 for separating elements
• Commercial / industrial: REI 60–120 depending on occupancy and sprinkler provision
• Escape routes: EI 30–60 minimum in most European codes

Step 2: Confirm assembly compatibility

The wall assembly must match the tested configuration in test report FIRES-CR-284-25-AUPE. Key parameters:

• Board thickness: 12 mm (CE-documented specification)
• Fixing method: as specified in DoP TRS-20250610F
• Frame centres: per test report
• Insulation type and thickness: per test report

Step 3: CE documentation package

For each project, the following documentation should be available:

• DoP (Declaration of Performance) — TRS-20250610F
• CE mark certificate — 1023-CPR-1565 P
• ETA — European Technical Assessment 24/0895
• Fire test report — FIRES-CR-284-25-AUPE

All documents are available from Terasun Europe on request.

Reaction to fire: Class A2

In addition to fire resistance (system performance), Terasun TSM has a reaction to fire classification. Fiber cement board is a mineral-based product — it does not contribute to fire growth.

Terasun TSM is an inorganic, asbestos-free cement board. It does not contain combustible polymers or organic fibres. This supports use in applications requiring non-combustible cladding.

For projects requiring detailed reaction-to-fire documentation, contact Terasun Europe for the full EPD (EPD-IES-0018268) which includes material composition data.

Applications where fire-rated TSM systems are specified

• Timber frame residential — fire separation between units and to escape routes
• Steel frame commercial — fire-rated shafts, plant rooms, escape stairs
• Refurbishment — upgrading existing partitions to meet current fire codes
• Industrial buildings — compartmentation between storage areas
• Schools and healthcare — EI 60/90 requirements for corridors

Summary: what to specify

• Board: Terasun TSM 12 mm, CE 1023-CPR-1565 P, ETA 24/0895
• Assembly: per fire test report FIRES-CR-284-25-AUPE
• Performance: E 120 / EI 90 / EW 120
• Documentation: DoP, CE certificate, ETA, fire test report — all available on request