Glass and Plaster
Natural ventilation is energy efficient and also ensures healthy indoor
air quality. The proper alignment of windows, doors, and landscaping
can improve cross ventilation and air movement. Ceiling fans are
much cheaper to operate than air conditioners.
In hot, dry climates, there is the thermal chimney, a design used in the Middle East for thousands of years. Two metal or wooden chimneys or ‘towers’ are incorporated into the building. The downdraft tower pulls air in over a moist pad as hot air is pulled out through an updraft tower at the building’s opposite end. Adding a wind scoop to the downdraft tower enables it to catch the prevailing breeze. In a hot, dry climate, evaporative coolers are most effective. In a humid climate, like Montréal, a dehumidifier coupled with an efficient absorption, evaporative, or refrigerative air conditioner may be a better choice than a conventional air conditioning system.
Using the natural air pressure differential between two different elevations by creating towers is called the stack or chimney effect. This causes automatic air movement up and through the chimney which creates a natural air flow. If the air intake is passed through sun-warmed material or naturally cooled material, the air temperature of the incoming air can be regulated and used to offset the costs of using mechanical heating and cooling mechanisms.
Although mechanical ventilation systems may still have to be used to heat and cool a building, using environmental design techniques can reduce their size and operating costs.