Passive and Low Impact Cooling and Ventilation Systems

Passive and low impact cooling systems vary slightly depending upon the climate zone for a building. However some concepts remain constant including the following:

1 Keeping a building narrow with ventilation openings minimum of front and back of a room permits good flow through ventilation;

2 Openings on more than front and back are even better, eg openings on 3 sides of a room;

3 Allowing the cool, fresh air to come in low and the hot exhaust air to expell high due to the convection currents of heated air;

4 Incoming cool air, particularly in a humid climate can be forced with small low cost fans. This creates a positive pressure in a building and forces hot draughts out of a space. In a hot dry climate the incoming air can pass over a cooling agent, eg water (pond, wet cloth, wet wall, etc) to naturally cool the air.;

5 Ventilation and glazing can be separated to allow view and air to be independantly;

6 A heat chimney which goes above the highest point of a building expels hot air and creates a healthy air flow. The process can be reversed with a fan in winter to send warmed air down to lower levels;

7 Planting around a building can cool breezes as well as providing shade to the structure and glazing. Deciduous plants can allow sun in winter and exclude it in winter. Deciduous trees are particularly useful on the North to the North West sides of buildings.