Climate change has put air distribution back in the spotlight as users look for more energy-efficient methods of moving air around. Joe Wieckowski, general sales manager of Colman Moducel, reports
OUR industry has a profound effect on the world's population, particularly those living in hot climates. Occupants of buildings across the globe benefit from comfortable and healthy environments thanks to improvements in plant, systems and designs.
Policies regarding climate change are directly influencing our industry, further encouraging the development of environmentally friendly products. And, with the demands of Part L and F shaping environmental controls, air distribution manufacturers are one of the major beneficiaries.
Grilles, louvres and diffusers can be found in most buildings in one form or another. Once regarded as peripheral, grilles and diffusers are now being viewed in a new light.
As a rule louvres are used for exterior applications, such as protecting external plant. They also add to the aesthetics of buildings, and are designed to cope with all that the weather can throw at them.
Grilles can can be sited virtually anywhere, even in doors, to enable air to pass from room to room. As most grilles fit the aperture of a standard ceiling tile, when walls are moved they can be repositioned.
The same applies to floor grilles, particularly in computer suites and data centres, where there is a constant need for flexibility to cater for increased racking and processing capabilities.
Apart from door-mounted grilles, the majority of applications require ductwork along with dampers and plenum boxes to act as an equalising chamber and the grille itself to transfer the air. Grilles deliver air for a wide range of applications, from small rooms to large exhibition halls and auditoriums. Aesthetics is often a key concern, hence the array of designs, materials and colours used.
High-profile examples of applications include the Ebor Stand at York Racecourse and the toll-booths on the M6.
Diffusers are just as flexible. The most common designs are nozzle and jet diffuser, often seen in aircraft cabins and coaches.
Proper selection is necessary to ensure adequate ventilation is provided. Diffusers are engineered with specific performance parameters inherent in their design, and they should not be specified simply on appearance alone.
Underfloor air distribution is often associated with computer rooms and data centres. But it is also becoming popular because raised flooring systems are cost-effective when designing open area office space.
Instead of installing an overhead system with ductwork and VAV controls, the underfloor system uses the floor module as a plenum. Air is then introduced at floor level. As it rises and mixes, it increases in temperature. Warm stale air is ducted out through the ceiling.
A major benefit of this approach is that, because air is introduced at a warmer temperature, outside air can be used more frequently for free cooling, and any indoor contaminants are lifted away as the air rises.
Displacement ventilation is most suitable for environments requiring high levels of ventilation, such as airports, atria, retail, food service areas, concert halls and lecture theatres.
Methods and locations of supply air entry and extraction can be discreet and compatible with the design of the building and any noise level requirements. Examples include decorative panels doubling as a support beneath tables in airport lounges, and in-stair applications with air being supplied between each tread.
With climate change becoming a driving force across our industry, there has never been a better time to take advantage of the benefits of air distribution systems that can ultimately determine and maximise the overall efficiency of air conditioning systems.