Describes the background to residential ventilation in the UK and its origin in the character of the housing stock. Notes the traditional leakiness of UK housing. Points to the major problem of condensation (35% of dwellings) and mould (17%). Compares fuel costs and indoor air temperatures in the UK with those of a number of other countries and considers the consequences for the choice of residential ventilation systems. Describes recent changes in UK building regulations concerning ventilation, insulation and airtightness. Notes increasing concern about NO2, CO and dust mites. Examines future problems and developments.

KEYWORDS: year 1997, Ventilation, housing, UK