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Treated, organic cellulose fibre insulation blown into party wall and floor voids to increase the acoustic barrier performance of existing structures.

Insulation is blown into the voids via a hose inserted through 100 mm diameter holes cut in wall panels and/ or ceilings. Alternatively, Celbar can be blown into floors if lifting some floor boards is an option.

Unlike panel or batt installations, loose fill takes up all the void space and acts as a compression spring on the wall or ceiling panels. A damping effect, additional to the normal acoustic absorption, reduces panel resonance which causes noise transmission aberrations at low frequency. There is a smooth transition from stiffness controlled absorption to mass controlled absorption.

The work can be completed with no disturbance to adjoining properties. Celbar manufacture has ISO 9001 Accreditation.

Quality Assurance:

  • Materials and equipment to be provided by ICC licensee. No substitutions permitted.
  • Installer must be trained and licensed by ICC.

Related Work:

Client is responsible for reinstatement of:

  • Fire integrity of panels.
  • Services disturbed during carrying out of the work.
  • Celbar is an excellent thermal insulator, therefore any electrical work should be carried out by a competent electrician using appropriately sized cables and protective covers for downlighters. Protective covers should be fitted after the Celbar installation to avoid the Celbar hose from dislodging them during the fill process.

Manufactured by the International Cellulose Corporation.

Related literature

The following content references this product:

Standard product features


The Celbar fibres are designed to pack the void at up to 45 kg/m³.


Oscar Iso-Mounts:

For improved acoustic performance for domestic ceilings, Oscar Iso-Mounts can be used to isolate ceiling boards from the joists, thereby breaking the path of vibration which is also a path for sound transfer through a rigid structure of ceiling, joists and floorboards. Oscar Iso-Mounts achieve an acoustically isolated ceiling with the minimum ceiling height loss (typically 6 mm), and all of the work can be carried out from the room below.

NBS Specification

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This product is associated with the following NBS Create clause:
45-55-45/360 Cellulose fibres

NBS Specification

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This product is associated with the following NBS clauses:

Product specification

An important note about specifying



Oscar Acoustics


+44 (0)1474 854902

Product reference

Celbar Loosefill


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Manufacturer details

Crowhurst Barn,
Crowhurst Lane,
West Kingsdown,
Kent, TN15 6JE
Tel +44 (0)1474 854902
Fax +44 (0)1474 853337
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