Recycled soundproof insulation

NBS Source NBS National BIM Library RIBA CPD Providers Network

Celbar - Environmentally friendly acoustic cavity fill

Request Celbar quotation

Celbar is one of the few insulation materials that cater for both soundproofing and the transfer of heat. In today’s energy climate, keeping buildings warm is a necessary element when designing and creating homes, hotels and restaurants. Celbar gives you the best of both worlds, quieten unwanted sounds whilst your buildings warm with Celbar soundproof insulation.

How soundproof insulation works

Our soundproof insulation works by spraying the Celbar insulation into the ceiling or wall cavity before the void or gap is closed. Alternatively, if the wall has already been completely sealed, a small hole can be drilled and the Celbar soundproofing insulation can be sprayed through the hole with a hose. 

Person filling a ceiling cavity with Celbar Soundproof insulation.

Installer filling a ceiling cavity with Celbar Soundproof insulation.

Both of these methods will improve the sound insulation of your walls or ceilings. The latter procedure will seal holes or cracks around the wall, as well as electrical outlets, removing those hard to reach areas you wouldn’t previously be able to fill.

For best results, use in conjunction with our Oscar Iso-Mount, acoustic hanger systems.

Celbar vs. man-made mineral wool

When designing our Celbar soundproof insulation, we had a plan to create a product that was both acoustically and thermally more effective than other man-made mineral wools. 

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. Lofts, ceilings, walls and floors are insulated quickly and efficiently with Celbar thermal sound insulation.

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

Celbar - Environmentally friendly acoustic cavity fill

Thermal Soundproof Insulation Testing

When developing soundproof thermal insulation for walls and ceilings, we wanted to get the correct results, so testing was necessary. 

We created a simple wall construction of 63 mm thick metal studs lined with 12 mm plasterboard on each side. Here were the results;

[a] with no sound control material used - Result 31 STC (Sound Transmission Class)

[b] with mineral wool sound barrier batt - Result 33 STC (Sound Transmission)

[c] with 38 mm of sprayed Celbar - Result 49 STC (Sound Transmission Class)

Celbar acoustic sound insulation provides superior sound transfer control demanded by designers, owners and occupants.

Fire-rated soundproof insulation

As mentioned above, our Celbar soundproof insulation is created from recycled, natural, paper-based materials and fibres that have been treated with the highest quality fire retardants. 

Celbar has been certified with a UL rating for flame spread and smoke-developed, giving the product the highest available rating possible. In addition to our UL rating, Celbar also boasts a Class 1 fire rating. Full fire test reports are available on request.

How is our soundproof insulation recycled?

Celbar is a naturally safe and recycled cellulose fibre. The fibre in Celbar acoustic, thermal, sound insulation is organic cellulose derived entirely from recycled macerated paper and treated with a borax compound to protect against fungus, insects and rodents. 

Its recycled material and low manufacturing energy requirements combine to produce one of the most environmentally friendly materials used in building construction.

We are proud to announce  that our Celbar soundproof insulation is:

  • Low embodied energy

  • Good for the environment

  • Easy disposal

  • Recyclable

Contact us

Get in touch with one of our soundproof insulation experts to find out more.

Contact us


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

Technical specification

Technical specification

NBS Source    Download product specification by NBS

Health & safety

There are no known serious risks to health associated with Celbar.  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 soundproof insulation is not subject to legislation applicable to mineral or vitrified fibre.  

As an added bonus, Celbar soundproof insulation is non-itchy!

KIER Group
Twickenham Stadium
Harvey Nichols
Grand Designs
Jaguar Land Rover
Mercedes AMG
Hilton Hotels and Resorts
Willmott Dixon
Network Rail
Rolls Royce