The paper presents some of the findings from a broader investigation aimed at determining thermal comfort design conditions for combined chilled ceiling/ displacement ventilation environments. A typical chilled ceiling/ displacement ventilation office has been created within a laboratory test room, in which the ceiling temperature can be varied over a range of typical operating values; the thermal comfort of eight female test subjects was then measured in the test room over the range of ceiling temperatures.

A new ventilated cooledbeam system concept with free cooling has been installed and monitored in a retrofitted office building in the Wartsila NSD Finland complex in Vaasa, Finland. Good indoor air quality and individual room temperature control has been achieved using ventilated cooled beams. Both cooling- and supplyair distribution functions were integrated in the same room unit. No extra costs were incurred for the low-energy system's freecooling loop.

An overview is given of the current position regarding the use of wind tunnel modelling and envelope flow theory for determining natural ventilation through large openings. The overview is, to a large extent, a personal one and is illustrated primarily by recent research carried out in Nottingham, some of which has yet to be published in full.