Celbar - acoustic thermal insulation

Acoustic cavity fill


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Recycled paper acoustic thermal insulation

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Fire rated
Celbar is recycled environmentally friendly acoustic and thermal cavity fill insulation/void fill insulation made from paper based materials treated for fire retardancy.  Celbar is UL rated for flame spread and smoke developed with the highest available rating.  A specially formulated borate compound gives Celbar fire resistant insulation a Class 1 fire rating.  Additionally, Celbar provides a barrier that resists penetration by fire.

Tests have shown that when packed together, this natural cellulose insulation material is acoustically and thermally more effective than man-made mineral wool.

How it works
Celbar is used as a cavity filler in walls or between floors either in conventional rigid construction or with isolated systems e.g. combined with one of our Oscar Iso-Mounts range for ultimate soundproofing performance.

View Oscar Iso-Mount range

Ceilings and walls are insulated quickly and efficiently with Celbar cavity insulation

Celbar cavity fill insulation can either be sprayed into the cavity before the void is closed OR where a void is already closed it is blown by a hose through holes to improve the acoustic insulation of walls and/or ceilings.  This seals any holes and cracks in the wallboard, around electrical outlets, plumbing and other irregularities so there are no compressed areas or voids to allow sound leaks or air infiltration.  When two layers of plasterboard are used, the Celbar cavity fill insulation is blown in before the second layer is fitted.

Loose fill cavity insulation
  • Recycled, fire resistant, low embodied, natural material
  • Machine blown for fast, economical, large installations

Superior sound transfer control

Celbar cavity fill insulation provides superior sound transfer control demanded by designers, owners & occupants.

Older properties with ornate ceilings benefit with Celbar cavity fill insulation blown into the ceiling void reducing noise from rooms above.  It is blown into the void through small holes cut into flat areas of the ceiling and repaired afterwards or if major refurbishment is taking place it is filled from above by lifting floorboards.

*Acoustic performance guide filling floor void space, typical overall improvement better than - 9dB*

A simple wall construction of 63mm thick metal studs lined with 12mm plasterboard on each side was tested:

[a] with no sound control material used - Result 31 STC
[b] with mineral wool sound barrier batt - Result 33 STC
[c] with 38mm of sprayed Celbar - Result 49 STC 

For the ultimate soundproofing solution use in conjunction with one of our Oscar Iso-Mount space saving acoustic hanger range

View Oscar Iso-Mount range


Thermal acoustic insulation

Consider a wooden rod versus a glass rod over a heat source.  The glass rod conducts heat readily, the wooden rod doesn’t.  Traditional mineral wool insulation is a mass of small glass rods, additional insulating power is lost when it is compressed and it is uncomfortable to work with.

Thermal performance guide filling floor void space, typical < U = 0.25 W/m2K.

A green product

Naturally safe recycled cellulose fibre.  Reconstruction of a building may necessitate removal of Celbar cavity fill insulation fibre.  It can be recycled or disposed of as a non-special waste to landfill.  Your local authority waste disposal will give advice on recycling. 

  • Low embodied energy
  • Good for the environment
  • Easy disposal
  • Recyclable

The fibre is organic cellulose derived entirely from recycled macerated paper and treated with a borax compound to protect against fungus, insects and rodents.  It also has fire protection built in.  Celbar cavity fill insulation has excellent thermal resistance and provides a high degree of thermal insulation.  Recycled material and a low manufacturing energy requirement combine to produce probably the most environmentally friendly material used in building construction, low CO2.  Incredible!

Celbar - acoustic thermal insulation Installations

Environmentally friendly insulation

Environmentally friendly insulation

Celbar is recycled environmentally friendly acoustic and thermal cavity fill insulation/void fill insulation made from paper based materials treated for fire retardancy. 

Celbar - acoustic thermal insulation Technical Specification

Health & safety

There are no known serious risks to health associated with Celbar recycled acoustic thermal insulation.  It is non-carcinogenic and any small release of fibre during installation or subsequent maintenance work is not hazardous or considered a ‘Health and Safety’ risk.  Celbar cavity fill insulation is not subject to legislation applicable to mineral or vitrified fibre.  As an added bonus, Celbar cavity fill insulation is non-itchy!


Celbar is manufactured by ICC, Houston, Tx 
ISO 9001: 2000 certification