The inside air and the mean radiant temperatures of two buildings, one built of brick having a flat roof and the other built of lightweight adobe and having a domed roof, were estimated through a thermal network analysis. The analysis was repeated for both buildings when their ceilings and inside wall surfaces were kept moist and evaporatively cooled. A design day for a hot, arid region was considered for the analysis. It is shown that the temperature of the moist surfaces is reduced appreciably and the floor and the air temperatures are also reduced by their heat transfer to the moist surfaces. When natural ventilation rate is high, the room air does not become uncomfortably humid. With low mean radiant temperature in the moist buildings, thermal comfort can be maintained for the occupants. The total area and the duration when the surfaces are kept moist, along with the natural ventilation rate, can be controlled by the occupants to provide thermal comfort when it is otherwise uncomfortable. The use of a domed roof with a hole in its crown can ensure high ventilation rates at low wind velocities and in buildings which cannot otherwise be sufficiently vented.
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