Natural ventilation of buildings has the potential to significantly save cooling and fan electrical energy.
However, it is still not widely applied, because only limited information is available on the thermal
comfort and indoor air quality of office buildings without air conditioning. Steady state ventilation air
flow rates were therefore systematically simulated using both analytical and airflow network methods for
different boundary conditions such as temperature and pressure differences across openings for different
opening types. Coupled airflow network and dynamic building simulations were carried outto determine
the annual thermal comfort and energy savings. The results for the three moderate climate locations
Germany, Italy and Turkey show that while indoor air quality can be easily maintained for all opening
typologies,the summer coolingpotential andthermal comfort stronglydepends onthenatural ventilation
strategy. Control over the openings is crucial for all cases, as otherwise the office rooms tend to cool down
too much even in summer conditions.