Designers are being encouraged towards passive cooling and natural ventilation in buildings. This will promote heavyweight buildings which utilise both fabric thermal storage and night venting techniques. In terms of energy consumption and carbon dioxide emissions, the new build sector is of relatively minor importance compared with the existing stock of high energy consumption buildings, many of which already contain air conditioning. This paper describes a new technique whereby new and existing buildings can be fitted with a low energy air movement system, which significantly increases the fabric thermal storage capacity of the building. This should eliminate the need for air conditioning whilst still enabling occupants to remain comfortable in summer.