Moisture transfer and vapor condensation in roof of large space buildings in hot humid areas

In view of the water dripping problem in a large sport centre in Hong Kong, conducts a theoretical study and a field study. The results show that moisture transfers in the porous thermal insulation material of roof leading to water vapor condensation in the hot humid area in summer. The accumulated condensate water would corrode and destroy the building envelope. Moisture transfer would deteriorate the thermal insulation performance of the building envelope leading to additional air conditioning load of the building. To solve the problem, suggests that the porous thermal insulation material should not be used in hot humid areas, and that the rational installing position and tightness of the vapor barrier is required.