Home > Companies > Knauf > Fire Protection to Floor or Roof Cavity: Knauf C-Form Soffit Lining CF2/13

The Knauf C-Form Suspended Ceiling system uses the minimum number of different components and is extremely easy and quick to install. The system is strong, and suitable for larger ceiling areas.

The Knauf C-Form Suspended Ceiling system can provide up to two hours fire protection and easily accommodates changes in level.

Features and benefits:

  • Recommended for large ceiling areas and long spans.
  • Recommended when creating deep voids.
  • Strong, and resistant to movement.

To be installed in accordance with Knauf’s recommendations and British Standards BS 8212-1995 and BS 8000-8:1994.

The C Form Ceiling system has been designed based on ‘self-weight’ only basis, confirmation of any additional loadings would be required to ensure system performance.

The fire resistance performances are for imperforate ceilings incorporating boards with all joints taped and filled, or skimmed according to Knauf recommendations.

Standard product features

Fire resistance (BS 476: Part 22):

60 minutes.

Suspension hangers:

900 mm.

Upper channels:

900 mm.

Lower channels:

450 mm.

System weight:

27.4 kg/m².

Fixings into substrates:

Fixings are used to meet performance constraint [confirmation is required from supplier to meet ceiling specification and any additional loading].

NBS Specification

NBS Create logo
This product is associated with the following NBS Create clause:
20-10-10/110 Gypsum board suspended ceiling system

NBS Specification

NBS Buliding logo
This product is associated with the following NBS clauses:

Product specification

An important note about specifying





+44 (0)1795 424499

Product reference

Fire Protection to Floor or Roof Cavity: Knauf C-Form Soffit Lining CF2/13

Suspension system

 - Suspension hangers:
[Knauf Soffit Cleats fixed to Knauf Strap Hangers]
[Knauf 25 x 25 mm Angle Sections]
[Knauf Soffit Cleats with Knauf 25 x 25 mm Angle Sections]
[Knauf Universal Brackets]


[600 mm]
[900 mm]
[1000 mm]
[1200 mm]
 - Upper support channel:

Knauf ‘C’ Channels



[600 mm]
[900 mm]
[1000 mm]
[1200 mm]
 - Ceiling channels:

Knauf ‘C’ Ceiling Channels



[400 mm]
[450 mm]
[600 mm]
 - Connecting clips:

Knauf ‘C’ Connecting Clips - To be fixed at intersection between upper support Knauf ‘C’ Channel and lower ceiling Knauf ‘C’ Channels.



 - Type:

Two layers of 15 mm Knauf Fire Panel

 - Horizontal board joints:

To be picked up Knauf Ceiling Channels

 - Fixings:

Knauf Drywall screws at 230 mm centres, reduced to 150 mm at the ceiling perimeter

 - Perimeter Sealing:

As per required interface detail to material abutment



30 mm Knauf Universal Slab RS45


[Taped and Jointed for a Seamless finish using Knauf Jointing Products]
[Taped and skimmed with Knauf Finishing Plaster]
[Knauf RMF [Ready Mixed Finishing] in accordance with General clauses]

Manufacturer details

Kemsley Fields Business Park,
Kent, ME9 8SR
Tel +44 (0)1795 424499
Fax +44 (0)1795 416261
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