Home > Companies > Siderise Group > SIDERISE CW-FS Perimeter Barriers and Firestops for Curtain Walling (formerly Lamatherm CW-FS)

Cavity barriers and fire stops to maintain continuity of fire resistance by sealing the gap between the compartment floors or walls and the external curtain wall both horizontally and vertically. The method of manufacture provides a resilient lateral compression property which assists installation, ensures the requisite tight fit and thereby enhances fire integrity. The materials comprise a one-piece product having a pre-compressed non-combustible rock fibre core. The products also have integral aluminium foil facings to provide a Class 'O' rating and excellent resistance to smoke. Lamatherm CW-FS SIDERISE Perimeter Barriers & Firestops for Curtain Walling is manufactured and designed to accommodate full façade movement, due to normal use loads, wind seismic and fire conditions Can be used in conjunction with SIDERISE CW-AB Acoustic Barrier Overlay - Facades (formerly Lamatherm CW-AB acoustic barriers).


  • Certifire approved. CF563.
  • Economical and easy to install.
  • Provides a smoke and fire seal.
  • Provides up to 300 minutes fire integrity and insulation.
  • Qualified acoustic performance.
  • Quality assured to BS EN ISO 9001.
  • Suitable for both horizontal and vertical applications.
  • Suitable for use in cavities/ voids up to 1200 mm wide.
  • Supplied in full sheets or pre-cut in strips to suit specific void dimensions.
  • Tested to EN1364 Part 4 in accordance with ETAG026 for up to 210 minutes.

Standard product features


1200 x1200 mm. Pre-cut products are available in 1 mm increments of width so as to provide a tight compressive fit within the cavity; contact manufacturer for more information.


1200 mm.

Thermal conductivity:

0.039 W/mK.

NBS Specification

NBS Create logo
This product is associated with the following NBS Create clause:
45-45-70/427 Mineral wool fire stopping

NBS Specification

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This product is associated with the following NBS clauses:

Product specification

An important note about specifying



Siderise Group


+44 (0)1656 730833

Product reference

[CW-FS 30]
75 mm thickness, 21 dB (Rw).
[CW-FS 60]
90 mm thickness, 22 dB (Rw).
[CW-FS 120]
120 mm thickness, 25 dB (Rw).
[CW-FS 300]
175 mm thickness, 27 dB (Rw).

Fixing brackets

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Manufacturer details

Forge Industrial Estate,
Mid Glamorgan, CF34 0AY
Tel +44 (0)1656 730833
Fax +44 (0)1656 812509
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