Displacement Ventilation Diffusers


Displacement Ventilation Diffusers

Key Features

4 Standard Models



Semi ? Circular


Steel and Aluminium Construction

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All model types are available in 6 standard nominal sizes;
400, 600, 800,1000, 1500 and 2000

and 6 standard heights;
750, 1000, 1250, 1500, 2000 and 2500.


Displacement ventilation systems, as the name implies, rely on a displacement process of the supply air into the occupied zone. Typically the supply air is introduced at low level and at a low velocity to displace the room air and provide layers of cool fresh air in the occupied zone while the extract removes stale air at high level. Supply air temperature differentials are normally low and offer the opportunity to take advantage of using fresh air based on (free cooling) for much of the year.

The SD range of displacement diffusers are ideally suited for use in areas with high heat loads requiring air volumes up to 2800 l/s. By using the effects of convection to lift the supply air from heat sources, whilst at the same time removing any pollutants, the air is then extracted at high level, thus creating an even temperature, draught free, clean environment.


The diffusers are constructed from steel and aluminium with the active area constructed from 5.5mm circular perforated aluminium giving a 37% free area or 10mm square perforated aluminium giving a 69% free area, the remainder of the unit is from sheet steel. A complete range of accessories is available including, spigot dampers, peripheral or bag filters, dividing rings and air direction vanes. 

The standard colour is White RAL9010 30% gloss although other colours and finishes are available on special request.


Four conventional shapes are available, Corner, Semi-Circular, Circular and Rectangular. More unconventional Trapezoidal and Hexagonal shapes are also available, on request. 

Model SD-1 Corner
Model SD-2 Semi Circular
Model SD-3 Circular
Model SD-6 Rectangular