Ian Rogers, Sales Director @ Gilberts Blackpool, diffuses his perspective on how to influence the impact of architectural design

Ambience: it’s at the root of how well a space works, whether work or play. How the occupants feel has a major impact on how successful you as an architect have been in the design. Yet there is one element that massively impacts the atmosphere of a space, that- more often than not- doesn’t even feature on your blueprints- the ventilation, and specifically, its delivery.

How ventilation diffusers deliver the air itself is a science, which influences occupant comfort. Locating them in the right location is important in itself. You need to balance flow of fresh air into the space (Building Regulations recommend an average in most commercial spaces of at least 10 air changes per hour but the precise number depends on occupancy and usage to maintain the IAQ ). 

However it needs to be delivered in such a way that the people below are not subjected to draughts or ‘cold dumping’, so that, ideally, it doesn’t even register on their conscience that they are too hot or cold. 

Energy efficiency and beyond…

So many of today’s building designs are influenced by BREEAM, LEED etc. It’s about reducing energy usage, creating sustainable environments. 

In an ideal world, all spaces would be naturally ventilated. That is not viable in every building- the changes in air pressure in a high rise block generated in ventilation exhaust shafts would be impossible to accommodate cost-effectively, even if one could design the air paths appropriately whilst optimising the use of the diverse spaces/zones within. 

Hybrid ventilation- which predominantly uses natural ventilation and switches to low-energy mechanical power only as and when necessary to maintain the air temperature and quality- could be an option, especially as currently most options available are stand-alone units that ventilate each individual zone. And the units can be concealed above ceilings.

Even when using mechanical ventilation, it is possible to manage the energy efficiency, via strategic positioning of the air delivery units (ADUs) throughout, and utilisation of developments in technology. To highlight one example, thermally-sensitive diffusers use temperature-reactive components i.e. no electricity to automatically adjust the direction of airflow to maintain the preset ambient.

The size, usage and design of the space will influence the style of diffuser chosen. 

An atrium for example will need the air to cover a long distance at height so a jet nozzle would be a suitable choice. 

In an open office with exposed ceiling, swirl diffusers achieve rapid intermixing if properly specified e.g. with a Coanda plate to encourage airflow horizontally and avoid cold spots. Their swirl dispersal of air also makes them great in offices with ceilings, often coupled with a square perforated face to integrate into the ceiling grid.  Whether exposed or integrated into the ceiling, they facilitate different layouts and use of the space in these days of agile working. Where precise direction of air is a criterium, multi nozzle diffusers provide the flexibility to set each nozzle exactly where needed, or you could choose square faced louvre diffusers which give you the flexibility to circulate the air in one, two, three or four directions. 

External facades with expanses of glass are subjected to temperature differentials and possible condensation- linear diffusers above can deliver a vertical curtain of air to minimise the effect. The latest evolution of linear diffusers (Gilberts ThermAcute™) feature thermally reactive components to adjust the airflow within seconds of detecting any variation from the preset. With their high airthrow- 5m- ambient temperature is maintained and  potential for condensate forming on the glazing is nullified. As the units activate thermally, there is no electricity/energy required- all positive for sustainability, carbon reduction and the carbon footprint.

Large spaces such as leisure venues often need spot cooling or heating: a drum louvre provides a stream of air horizontally or vertically with the rise and fall of the drum addressing temperature variations within the internal air (from basic physics we all know that hot air rises). Again, the advent of thermally-activated ADUs in such an environment can play a part, maintaining the occupant comfort without them even realising/ acknowledging consciously or subconsciously that they have become too hot or too cold…That is the secret of a good ventilation strategy.

An auditorium requires low level ventilation- often sited under the seats. …the list goes on. 

Diffusers = architectural design

Increasingly, architects are realising that the diffuser can be part of the aesthetic whether it discreetly blends into the design or stands out. Historically, innocuous colours have been chosen for the finish so that the diffusers blend into the ductwork or ceiling. Today, we are seeing greater experimentation- red, blue, yellow, matt, gloss, metallic and stone effects. It’s possible to specify your own faceplate design- to feature a brand logo or message screen-printed or perforated into the face plate. 

It is even possible with the Coanda plate on a swirl diffuser to have the plate made from almost any material, even back-light it!

Whilst as architects you often leave such minutiae to the specialists- the building services consultants, engineers and manufacturers, the choice of ventilation will inevitably impact on the interior design. Is it time to give it a little more thought? If so, turn to the experts to support: they can not only advise, but, if chosen with care, should be capable of developing a bespoke answer that compliments your blueprint.