This study examines the performance of a novel air-to-air heat/mass exchanger using a fibre paper coated with a solid desiccant material. Theoretical analysis and experimental testing were carried out to determine the ability of the heat and mass transfer across the heat exchanger (i.e., between fresh air entering the room and exhaust air out of the room). Two sets of operating conditions, representing summer and winter operations, were examined and for each of these a range of airflow rates was used. Results showed that the efficiency of the heat exchanger could be as high as 87% in winter condition and 86.83% in summer. The efficiency was found to decrease with decreasing enthalpy difference between the two airstreams, and increased with increasing flow rates of both airstreams. Under the condition of equal fresh/exhaust airflow rates of 905m³/h, about 3.4kW of energy in winter and 2.5kW in summer can be recovered through use of the exchanger. The investigation indicates that the fibre heat exchanger has the advantages of being cheaper and more efficient than with conventional heat exchangers.