Natural Ventilation Systems

One of the major challenges faced by the modern building designer in recent years has been the search for new ways to significantly reduce energy consumption and the avoidance of what was once labelled sick building syndrome. 

Faced with rising energy costs, ever increasing environmental damage and the resultant politically-driven legislation, many businesses have now become critically aware of their building’s energy consumption, carbon emissions and the working environment. The collective result of which has been to find new ways to encompass a universal solution.  Welcome to Windvent and Natural Ventilation Systems.

Why Choose Windvent?

Windvent systems are logical and suitable strategies for many buildings, from low rise dwellings and schools to small or medium sized offices, recreational or public buildings. They are highly cost-effective once installed, when compared with the maintenance and operational costs of conventional air conditioning or mechanical ventilation systems. Natural ventilation has been proven to improve staff and pupil productivity and our systems have been successfully installed in many commercial and industrial premises across the UK. 

Midtherm Windvents operate on aerodynamic principles. They are driven by the provision of an air thermal effect with the corresponding extraction rate flow and a natural function of balance and equilibrium. To activate the process, the only energy required is for a low voltage controller unit that drives the dampers, modulating the input of natural air. 

Schools and commercial buildings where Windvents have been installed have gained from reduced CO2 emissions, energy savings and occupants’ wellbeing. A fresh cool air supply delivered via natural ventilation has been proven to reduce staff sickness, reduce energy waste and increase occupants’ productivity compared to offices that have no provision to ventilate automatically. 

Windvents have acoustic lining as standard, the thickness of which can be increased up to 50mm should required noise levels dictate, thus providing efficient, economical and aesthetic acoustic solutions to ventilating buildings. 

How A Windvent Works?

The natural ventilation system operates on well-established aerodynamic principles. As air flows around a terminal, positive and negative pressure areas are generated. On the positive side air enters the louvres of the terminal and is directed down through the internal vanes into the room below. This action is brought into equilibrium by the negative pressure on the leeward side of the terminal, which induces air to leave the terminal drawing the stale hot air from the room below. This process is aided by the thermal stack effect, resulting in a flow of air in and out of the room.

Windvent in Practice

How does the Windvent compensate for changes in weather?

Automatically adjusting dampers are provided within the system to allow for differing temperatures, wind conditions or air quality requirements.

These dampers are linked to a programmable control system which allows for the ventilation rate to be controlled by internal and external sensors. Night purging can be achieved when the dampers are set to fully open during warm nights when a building is unoccupied. Conversely, in the colder months, the controller will reduce the flow of air to trickle ventilation rates as specified in the CIBSE guide and hence retain the boiler heated air in the occupied space.

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