**3.3 Removal**

Removing, as a passive cooling action, refers to the removal of undesirable gained heat in interior or exterior spaces in a building. Natural ventilation normally is the main strategy used to take unwanted heat out of the buildings. It depends mostly on pressure differences to circulate air between inner and outer spaces, allowing air to enter or escape from buildings. Devices like windows, openings,


**45**

*Advances in Passive Cooling Design: An Integrated Design Approach*

wind towers, sunspaces, earth tunnels, and roof openings are used to move air

*The effects of trees on surface and air temperatures in identical spaces (author).*

Natural ventilation follows three main principles that designers should understand well in order to induce passive ventilation into any building's design, which includes stack ventilation, Bernoulli's effect, and the Venturi effect. These three principles uses air pressure differences due to height, air temperature, or wind speed, to pull air to or from buildings. Therefore, the main concept of passive ventilation design is achieved by maximizing the use of one or more of the three principles in

Stack effect depends on temperature differences to circulate air, as hot air rises up and cool air sinks down (**Figure 6**). The design for ventilation that depends on stack principles is achieved by letting hot air rise up within spaces or specific devices and exhausting it from upper openings, which allows it to be replaced by cooler air from lower openings. The designer's role in the process is represented in designing air movement and its exhaustion and penetration, which includes the

1.Accelerating the rising of hot air by designing a long vertical space that crosses through the building section, like atriums, double-skin facades, solar chim-

2.Designing inlet openings for cold air to enter the building from a well-planned and controlled cold space like shaded courtyards or urban spaces, basements, etc.

3.Increasing warm air to activate the stack effect and accelerate the ventilation process using devices like sunspaces, solar chimneys, and skylights in the

*DOI: http://dx.doi.org/10.5772/intechopen.87123*

through a building.

**Figure 5.**

*3.3.1 Stack effect*

following methods:

neys, or wind towers

building's design

order to induce natural ventilation.

**Table 4.** *Landscape variables (author).* *Advances in Passive Cooling Design: An Integrated Design Approach DOI: http://dx.doi.org/10.5772/intechopen.87123*

**Figure 5.** *The effects of trees on surface and air temperatures in identical spaces (author).*

wind towers, sunspaces, earth tunnels, and roof openings are used to move air through a building.

Natural ventilation follows three main principles that designers should understand well in order to induce passive ventilation into any building's design, which includes stack ventilation, Bernoulli's effect, and the Venturi effect. These three principles uses air pressure differences due to height, air temperature, or wind speed, to pull air to or from buildings. Therefore, the main concept of passive ventilation design is achieved by maximizing the use of one or more of the three principles in order to induce natural ventilation.
