Passive chilled beams systems are rapidly being recognised as the air conditioning technology of the future, and a key component to achieving an Australian Building Greenhouse 5 SEDA Star Rating.

Utilising around 20-30 per cent less energy consumption than a traditional variable air volume (VAV) system, chilled beams operate by pumping chilled water through radiator like cooling elements located above a perforated tile or open grid ceiling.

Within an office, people and computers heat the air, which rises through the perforated ceiling. This air is in turn cooled by the radiant chilled beams. This cooled air is returned to the Office space by natural convection movement (through the perforated ceiling) back to the occupants. Simultaneously, fresh external air is continuously provided to the workplace and exhausted out without being recirculated.

As hot air is rising and chilled air and fresh air is falling continually through the perforated tiled ceiling, it is imperative that the ceiling offers low or zero resistance to the air flow.

Hence the requirement to install all acoustic treatment to the concrete soffit.

To maintain a sensible and quiet workplace environment, it is important that an area equal to at least 70 per cent of the ceiling space be of an absorbing nature with a noise reduction coefficient greater than 0.75. This will achieve a respectable reverberation time within an open plan office, allowing for subdued conversations that do not encroach upon others.

Envirospray 300, from Enviro-Acoustic has been adopted by the chilled beam system as the only absorptive product that can be installed on the underside of the concrete slab for the following reasons:

* Excellent visual appearance. As the ceiling grid has a large “open area” the slab above can be seen by the public and Envirospray 300 in steel grey has a neat flat finish that is architecturally acceptable.

* Fast installation time. One crew can install 200m² per day thus ensuring no hold up for following trades or Builders Program of Works.

* Envirospray 300 can be applied after hanger rods, mechanical services, sprinkler pipes and other slab fixed brackets have been installed.

* Being a 100 per cent recycled product, non toxic with low embodied energy, Envirospray 300 has premium acceptance in Greenhouse Rated buildings.

* Where no perforated ceiling is installed, Envirospray 300 may be installed with an extra flat finish in a range of lighter colours.

* Commercially competitive pricing.

* Envirospray 300 has an excellent low thermal conductivity of 0.0384 W/m.oK