Awareness of the deterioration of indoor air quality in energy efficient buildings is growing. Apprehensions of the effect of airtight envelopes, reduction of ventilation rates, increased insulation and reliance on technological systems is promoting emerging new research in this field. This paper discusses recent findings and presents preliminary results of an indoor air quality investigation in energy efficient homes in the UK. A case study approach was adopted; the case study buildings consisted of a row of six new build homes in Northern Ireland which utilize MVHR, are built to an airtightness of below 2m3/m2/hr @ 50 Pascal's, and constructed without a central heating system.

Measurement parameters include temperature, relative humidity, and carbon dioxide. Occupant interviews were also conducted to gain information on occupant activities, perception of the interior environment, building related health and building use. Indoor air quality data of this nature is essentially lacking, particularly in the UK context. The findings will provide relevant data on the applicability of air-tight, mechanically ventilated homes in a UK climate, with particular reference to indoor air quality. This information can then be disseminated to aid the development of effective sustainable building design that is appropriate to localized climatic conditions and sensitive to the health of building occupants.