The Siderise CBX Flexible Acoustic Void Barrier is a high-performance, flexible foil faced glass fibre composite quilt designed for free-hanging installation in suspended ceiling voids, directly above partition lines.

It significantly improves airborne sound insulation by reducing flanking noise between adjacent rooms.

The CBX quilt consists of a central heavy mass-loaded membrane with an anti-creep layer, flanked by foil-faced glass fibre insulation for thermal and acoustic performance.

Despite its thin 40mm profile, it delivers a tested sound reduction of 33 dB Rw (to BS EN ISO 140-3:1995), making it an ideal solution for both new build and refurbishment projects where minimal disruption is critical.

It is fully compliant with UK Building Regulations, offering a reaction to fire classification of B-s1, d0 (EN 13501-1), suitable for wall and ceiling linings.

Specification:

Thickness: 40mm

Width: 1200mm

Length: 2000mm

Dimensions: 2.00m (W) x 1.20m (L) x 40mm (T)

Reaction to Fire: B‑s1, d0 (EN 13501‑1)

Acoustic performance: 33 dB Rw (BS EN ISO 140‑3:1995)

Composition: Central mass-loaded membrane, anti-creep layer, foil-faced glass fibre insulation

Installation: Free-hanging via mild steel angles to soffit

Overlap requirement: Minimum 75 mm at vertical joints

Weight: Approx. 5–7 kg/m² (est., typical composite quilt)

CBX Acoustic Foil Faced Glass Fibre Ceiling Quilt Features:

 · High acoustic performance: Achieves 33 dB Rw sound reduction (tested to BS EN ISO 140-3:1995)

 · Thin & flexible: Only 40 mm thick – ideal for tight ceiling voids or retrofit applications

 · Fire rated: B-s1, d0 reaction to fire – meets UK Building Regulations (Approved Document B)

 · Quick installation: Easily hung using mild steel angles and standard fixings

 · Improves room-to-room separation: Reduces flanking noise via shared ceiling voids

 · Low disruption: Perfect for occupied buildings and remedial acoustic upgrades

 · Durable construction: Multi-layered composite with central membrane and glass fibre layers

CBX Acoustic Foil Faced Glass Fibre Ceiling Quilt Applications:

 · Suspended ceiling voids above partition walls

 · Office fit-outs and acoustic upgrades

 · Commercial, healthcare, and education buildings

 · Refurbishment projects requiring minimal ceiling access

 · Enhancing acoustic performance between rooms sharing a plenum

 · New build or remedial treatment in multi-occupancy spaces

CBX Acoustic Foil Faced Glass Fibre Ceiling Quilt Installation Guide:

 · Prepare the void:

Ensure the soffit and partition line are clean and accessible.

Measure the space and pre-cut CBX quilts if necessary.

 · Fix top edge to soffit:

Use mild steel angles to clamp the quilt to the soffit.

Allow the quilt to hang freely above the suspended ceiling grid.

 · Ensure vertical overlap:

At all vertical joints, overlap adjacent quilts by at least 75 mm.

Secure with insulation pins and seal with foil tape for airtightness.

 · Accommodate services:

For penetrations (pipes, cables), make star or slit cuts.

Fold back flaps and seal around services with additional quilt strips.

 · Secure base:

Return excess quilt 150 mm above the suspended ceiling, or fix base using clamping method similar to top fixing.

 · Inspect and seal:

Check for any gaps or loose areas.

Reseal or re-fix as necessary to maintain acoustic continuity.

*Further information may be found in our Downloads section.

Fairly easy access to all PDF files.

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