New window gets top marks for ventilation

Tests undertaken on a new ventilating window have shown that the window allows for natural ventilation and improved air quality and reduces the need for mechanical plant for ventilation and cooling in classrooms.

Called Rapidvent, the window has been launched by leading UK design and manufacturing company, Britplas, who are best known for their specialist healthcare windows. The window’s design includes a super-tough stainless steel perforated mesh which allows for the flow of fresh air whilst assuring the safety of the classroom’s occupants.

Leading global design, engineering and management consultancy, WSP, were commissioned by Britplas to undertake a Technical Performance Study of the new Rapidvent window.

WSP devised a series of tests to demonstrate Rapidvent’s performance in a school, comparing the resultant environmental conditions within a test model against an identical building with a standard top-hung window on 100mm restrictors, as typically installed in school buildings.

The tests were designed to explore internal temperature, ventilation rate, air quality and daylight. Additionally, the properties of the window’s mesh were examined using computational fluid dynamics (CFD) allowing the behaviour of air streams within the classroom to be analysed.

The test results were overwhelmingly positive and showed that compared with standard or restricted top hung windows, the Rapidvent could deliver a 10°C reduction in peak and average internal temperature, improve the natural ventilation and deliver a 50% lower carbon dioxide concentration.

The CFD results also showed that the fresh air delivered to the classrooms by the Rapidvent penetrates significantly further into the back of the room, reducing the potential for stagnation.

These results mean that the Rapidvent window system addresses the key criteria associated with regulatory standards BB101.

Further analysis of energy and economics demonstrated a potential £5,300 saving on build costs, in addition to a £120 per year reduction in energy costs per classroom.

Commenting on the new window, Kevin Gorman of Britplas, said, “The results of the desk top studies confirm the ability of Rapidvent windows to provide naturally ventilated buildings that are both comfortable and stimulating for its occupants and users, at a cost that is positive both environmentally and in monetary terms.”