HVAC (Heating, ventilating air conditioning)system is used to keep indoor air quality. Thepurpose of the traditional HAVC system isproviding a comfortable environment andventilating the indoor air pollutants. Recently,with the quality of life increasing, people havemore requests for indoor air quality. However,we found that the HVAC system still stressindoor ventilation, and temperature andhumidity adjusting.

Thermal building simulations (TRNSYS) werelinked to nodal airflow network simulations(COMIS) for a detailed ventilated double-skinfacade calculation of performance. Thevalidated simulation model can be used tooptimize the ventilated facade design in respectto reducing the solar heat gains during thesummer period by controlling the exhaustairflow. This may result in significant energysavings and a reduction in systems cooling size.This work evaluates two different controlstrategies of ventilated faqade designs in respectto cooling load reductions.

Double-skin facade (DSF) is an architectural/ engineering solution developed from the need to increase comfort in buildings with full glazed facades. The actual concept of holistic approaches to the building energy system considers DSF as an element of an Advanced Integrated Facade. DSF were developed for colder climates and uncertainty remains on their applicability to warmer areas due to higher probability of overheating.

Thermal mass can be used in buildings toreduce the need for and dependence onmechanical heating and cooling systems whilstmaintaining environmental comfort. Activethermal mass strategies further enhance theperformance of thermal mass throughintegration with the Heating, Ventilation andAir Conditioning (HVAC) systems. For thedesign of new buildings to include activethermal mass strategies, experience fromoperational projects and design guidelines arenormally used by engineers.

Thermal mass activation (TMA) can assure, incertain cases, thermal comfort conditionswithout the need of air conditioning systems.Even if other cooling systems have to be used,night ventilation significantly reduces theduration of the working time of additionalcooling systems.The desired night ventilation rate (NVR),could be achieved using either mechanicalventilation, natural ventilation or a combinationof these two methods (hybrid ventilationsystem).In this paper, we will investigate thefeasibility of night cooling using naturalventilation for a residential building in a hotregion of Fran

Subtask B of the IEA-ECBS Annex 44"Integrating Environmentally ResponsiveElements in Buildings" deals with thedevelopment and the optimisation of integratedbuilding elements. The results of two modelbuildings exemplify the impact of buildingconcepts and user behaviour on the operation ofthe building. The analysis shows that innovativebuilding concepts and elements, which to someextent are being realised at the moment, need totake into account system integration andintelligent planning in order to achievesatisfactory results.

Misawa Homes have developed a homeaiming a zero annual energy balance, definedas the energy consumption over production byusing solar energy, in 1997. According to oursurvey, energy balances of what we call ZeroEnergy Hoines built in Tokyo or southern areaof Japan were actually zero but it was not thecase in those homes built in northern areaAs one of the top housing distributors, werealize that it is our responsibility to developand provide environmentally friendly homesto prevent global warming.

Building services create customised, user-oriented and controlled conditions for thevarious activities taking place on real estatesand related premises.This paper presents an outlool< of buildingservices trends in Finland. The outlook of thefuture development of building services ispresented in the form of technology roadmaps.Overall, the building services roadmap consistsof six separate roadmaps.

Tall buildings have traditionally been sealed andmechanical ventilated. In recent years advanceshave been made allowing the natural ventilationof tall buildings for a part of the year. Themotivation has been both energy savings andoccupant comfort. The projects realized thus farwork on the mixed mode principle. Naturalventilation is employed for a proportion of theannual period. However under certain wind andexternal temperature conditions mechanicalsystems take over.

There is an obvious and indisputable need for anincrease in the efficiency of energy utilization inbuildings. Heating, cooling and lightingappliances in buildings account for more thanone third of the world's primary energy demand.In turn, building stock is a major contributor toenergy-related environmental problems.