Passivent natural ventilation is helping car showroom design to realise the dream of reducing carbon footprint, whilst simultaneously achieving a much reduced energy demand
As part of its market strategy, Honda (UK) is building a new 600m2 car showroom on a brownfield site in Romford, Essex. Not only has the showcase building had to comply with Honda’s own environmental commitment, but with the local council’s requirement that a minimum ten per cent of energy needs are produced using on-site renewable energy.
A services solution, developed by building services design specialists Cunnington Clark, has been found largely by utilisation of Passivent natural ventilation technology. As a result, conventional air conditioning cassettes for the showroom and customer service areas have been replaced with Passivent Aircool inlet louvres at low and high-level and Passivent Airstract roof terminals. This has brought about an energy demand reduction of over 80 per cent, a ‘very good’ BREEAM rating and a ‘good to best’ sustainability appraisal.
In all, some 36 modulating wall and ceiling Aircool units draw fresh air into the space on demand, maintaining internal air temperature and CO2 at preset levels. Natural air movement principles, in which warm air rises, are harnessed to exhaust the warm, ‘used’ internal air through the six roof-mounted Airstract terminals.
Passivent’s system functions 24/7, allowing night air to be drawn in when the building is unoccupied to provide ‘free’ cooling. Underfloor heating powered by a ground source heat pump ensures the showroom remains comfortable in the cold winter months, with the heat pump providing chilled water through the pipework in peak summer temperatures to maintain the space temperature at below 28degC.
Predictive modelling
This combination, coupled with the building’s increased thermal mass, is predicted via thermal modelling to reduce energy demand from 61551 kg/CO2 to just 11058kg/CO2 - a saving of 82 per cent compared with traditional showroom design. A BREEAM (Building Research Establishment Environmental Assessment Method) Retail Design & Procurement Pre-Assessment classified the building as thus achieving a ‘very good’ rating, and a regional sustainability appraisal using the SEEDA (South East England Development Agency) checklist concluded a sustainability practice level of ‘good to best’ for the project.
Dean Barker of Cunnington Clark observed: “We aimed to create a benchmark energy model for Honda. The design brief was to design the services for an environmentally friendly building in accordance with the planning requirement to achieve at least Building Regulations Part L and the Greater London Assembly’s energy standards, and to show Honda’s commitment to reducing its environmental impact. The showroom is also to be a showcase for Honda’s new corporate image.
“We modelled the building using Passivent motorised louvres at both high and low level and roof-mounted terminals. The concept has been used to great effect in office and school environments and we felt the same technology would work in a showroom environment.”
Passivent is part of the Building Product Design Group.
