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Siderise CW-AB | Acoustic Barrier Overlay for Façades – Technical Data

Version: 1.01 - Release Date: January 2023


The Siderise AB10 is a flexible acoustic membrane for use as a mass-barrier above Siderise CW-FS fire stops in curtain walls. Using this acoustic upgrade can offer a significant improvement to the acoustic performance of the firestop. Incorporating mass barriers such as the Siderise AB10 into slab-edge details is often crucial for controlling floor-to-floor sound transmission.
Siderise AB10 is quick and easily to install, and is suitable for use in all curtain walls. The product is thin and flexible, and is designed to accommodate façade movement, unlike traditional mass-barrier materials such as steel or plasterboard.


  • Reduces floor to floor sound transmission

  • Ideal for remedial treatment after installation of firestops

  • Accommodates façade movement

  • Deforms to contours

  • Quality assured to BS EN 9001

Product Description

Siderise AB10 comprises a high mass limp elastomeric membrane applied to a dense acoustic foam layer. The upper surface is faced with reinforced aluminium foil. The entire product is 12 mm thick.

Acoustic Considerations 

The fire stop between the floor slab and façade represents a point of significant potential weakness in vertical sound transmission between floors.

Our facades technical team can provide guidance around using this acoustic upgrade to meet the project's acoustic performance requirements.

Acoustic Performance

As the AB10 is sold as an acoustic upgrade for our CWFS firestops, we have not tested its standalone performance, however for the purposes of assessment by project acoustic consultants, the Weighted Sound Reduction index (dB Rw) of the mass barrier layer alone is presented below in Table 1. See ‘acoustic improvement’ below for the sound reduction index of this product in combination with the CWFS fire stop.
Additional acoustic performance increases can be achieved by combining the AB10 and CWFS with the Siderise CVB/C-10 cavity barrier. Contact our facades technical team at for performance guidance or 1/3rd octave test data.

Table 1 - Barrier grades & Weighted Sound reduction index

Element Thickness
Surface Mass
Acoustic Performance
(dB Rw) 
AB10 (mass barrier layer only) 5.5 10.5 32 

Acoustic improvement to the firestop zone

The Siderise AB10 has been developed for use with our Siderise CW range of perimeter barriers and fire stops for curtain walling.

Siderise fire stops already offer a good level of sound insulation performance (typically 22-25 dB Rw). This can be increased to 37 dB Rw by the addition of a Siderise AB10 overlay.
If further performance increases are required, our CVB/C-10 cavity barrier can be used in addition to achieve up to 51 dB Rw.

Technical Specification

Form supplied (mm) 2000 x 1200 sheet or cut strip available 
Colour Silver face 
Finish Aluminium foil facing to top side 
Thickness (mm) 12 
Surface mass (kg/m210.5 
Central mass membrane Polymeric barrier 
Fire performance B-s2 d0 


Siderise CW-AB acoustic product environmental properties:

  • They contain no Volatile Organic Compounds (VOCs) and no very Volatile Organic Compounds (vVOCs). 
  • Zero Ozone Depleting Potential 
  • Zero Global Warming Potential 
  • Recyclable

Additional Information

The following information is available upon request or via download from the website:

  • Safety Data Sheet

  • Standard Details

  • NBS Specification Clause

Technical Support

For technical advice or support please contact:

For Installation Training or Site Inspections please contact:


The information in this datasheet is believed to be accurate at the date of publication. Siderise has a policy of continuous product improvement and reserves the right to alter or amend the specifications of products without prior notice. Siderise does not accept responsibility for the consequences of using the products described outside of the recommendations within this datasheet. Expert advice should be sought where there is any doubt about the correct specification or installation of Siderise products.

Published Version: CW-AB_v1_01_2023013_1546