Improved levels of thermal insulation for dwellings in W.Germany have substantially reduced thermal transmission losses, so that ventilation heat loss has become much more important component of total building heat demand. Amount of heat appears important enough to justify considering heat recovery from ventilation air residential buildings. Describes 3 examples of exhaust air recovery from flats in an apartment building. Provides details of air change rates.
Discusses minimum ventilation necessary for occupied buildings and finds that occupiers minimum needs are based on dilution of body odours and that in Britain a high ventilation rate is necessary to reduce humidity. Describes two electrical solutions to the ventilation problem. The first is a combined ozone and ultra violet irradiation to oxidize the malodours. The second is the application of a heat pump dehumidifier to remove excess moisture in mild weather.