Passivent

Minimising energy consumption and carbon emissions in commercial, industrial and domestic buildings is being achieved through new developments from Passivent Ltd, the UK’s leading supplier of natural ventilation systems.

Passivent ‘commercial’ natural ventilation systems are proven in real life to be one of the strategies to attain up to an A rating under the new Energy Performance Certificate. Their performance enables their qualification for credits under the BREEAM verification system (often helping buildings to achieve at least a ‘very good’ rating) and towards achievement of Building Regulations Approved Document L(Conservation of Fuel & Power). Further, they reduce energy consumption over air conditioned buildings by up to 50%, yield 15% savings on capital costs, 75% savings on maintenance costs, and eliminate the need for a separate plant room: in one installation* the Passivent system is being calculated at reducing energy demand by up to 80%!

In a domestic environment, independent testing using SAP software on a three-bedroomed house with four ‘wet’ rooms (kitchen, utility, bathroom, en-suite) showed that there was no better solution to achieve the Code for Sustainable Homes’ Level 3 or better than Passivent Passive Stack Ventilation. In a similar three bedroomed, four wet room apartment, the Passive Stack option attained almost 10% improvement on the TER.

The savings are achieved by harnessing the physics of natural air movement, of pressure and temperature, similar to how a chimney functions. Warm internal air rises naturally; higher external air pressure moving across the roof draws the ‘used’ internal air out of the building through strategically placed terminals.

As air movement is constant, the Passivent system functions 24/7. This also provides effective night cooling as internal and external temperatures have a higher variance at night, increasing convection and removal of surplus heat gain within the building, minimizing energy consumption to bring the building down to the required temperature, helping ensure a pleasant, fresh environment within the next day and reducing incidence of ‘sick building syndrome’. Research shows people’s performance-be it worker output, student learning or health- is improved in naturally ventilated buildings.

Passivent is a founder member of the NatVent EC-EU-funded project co-ordinated by the Building Research Establishment to develop practical natural ventilation solutions for the commercial sector, and is developing “smart” solutions to promote adoption of natural ventilation. The company is the UK’s leading designer and supplier of natural ventilation systems for both domestic and commercial applications. The company has contributed to the BISRIA guide BG2/2005 Wind Driven Natural Ventilation Systems, as well as being members of the DfES steering committee on ventilation guidance for schools, Building Bulletin 101