Roof ventilation turrets use external wind and temperature to improve indoor air quality (IAQ) as part of a sustainable ventilation system. Unlike mechanical ventilation systems, natural ventilation uses a minimal amount of energy and is subsequently cost-efficient.

Natural ventilation systems are becoming increasingly popular in schools and offices, as the fresh air circulation helps to improve concentration and reduce absenteeism.

Often designed to be in keeping with the architectural aesthetic of the building, the roof-mounted ventilation terminals are typically constructed using aluminium, GRP or ABS. They are suitable for installation on both flat and pitched roofs.

Passive stack terminals make use of passive stack ventilation (PSV), which is the most common type of natural ventilation. PSV combines cross ventilation, buoyancy (rising, warm air), and the venturi effect (suction caused by wind passing over the ventilation terminal).

Displacement terminals utilise displacement ventilation, which is especially suitable for night cooling applications and for large spaces, such as sports halls and auditoriums. The turret typically features at least two separate chambers: one for cool incoming air, and the other for warm, outgoing air.

The ventilation terminals can feature integrated fans, for assisted ventilation, as well as integrated light pipes, to make use of natural daylight and to further reduce energy costs.