Many houses in Japan have crawl space between the lowest floor and the earth ground which is about 50 cm in height. This is considered as protection against corrosion of wood materials in the floor. Japanese building codes recommend ventilation with outdoor air in this space. In our field research, we found condensation in the crawl space in summer. This is due to low temperature of the ground and high humidity of the outdoor air which is typical of the Asian climate.
There is a substantial gap between truly energy-efficient construction and what is currently being built. The problems range from lack of training to carelessness. But there are ways to cure the problems and bring best practices into widespread use.
Fungal spore content in dust accumulated in air ducts was investigated in 24 mechanically ventilated single-family houses of which 15 had also a central air heating system. Dust was collected from the ducts simultaneously with cleaning of the ventilation systems. Besides spore concentrations and flora of culturable fungi, total fungal spore concentrations were determined in dust samples by the aqueous two phase technique and spore counting with epifluorescence microscopy.
Draughtproofing the doors, windows and other sources of excessive air leakage of a dwelling can be an effective and relatively inexpensive means of improving comfort and reducing heat loss by natural ventilation. The doors and windows considered in this digest are existing components not originally designed for draughtproofing. Products for general use on these components have to fill a wide range of gap sizes, be durable and retain the ease of opening and closing.
Remodeling is the perfect time to improve daylighting, direct gain heating, and shading with passive solar techniques. It can also provide the best opportunity to add solar water heating or even photovoltaics to a home.