The test house is located in the Institute's laboratory hall. This new facility (see above) will mainly be used for the study of alternative ventilation strategies in tight houses. However it will also be used for basic air infiltration research. The main reason for building thehouse indoors, is to obtain a controlled environment both with regard to the ambient temperature and the flow rate of outdoor air supplied. Therefore the house is well suited for use in connection with the development of different measuring methods and in particular the determination of their accuracy (the accuracy of methods for measuringthe infiltration rate is more or less unknown at present).