Study Wind Patterns

• The north and west sides of a house are most exposed to the cooling effects of winds following the passage of a cold front; this outcome is most negative during the winter season. Topography, vegetation, and other buildings both on and off a particular site frequently modify these general conditions. However, wind blows most commonly from a westerly direction throughout the United States. Unlike sun, wind is not as precisely predictable. In the summer, the prevailing wind is from the south and southwest, and during the cool season it shifts more to the west and northwest (Figure 3-26). Wind carries away the heat of the house and affects the amount of energy required for heating and cooling. In broad terms, wind blows from all compass directions throughout the year. On the other hand, wind exposure is not desired when air temperatures drop below 70°F. It is best to refer to weather records kept by the National Weather Service to obtain more precise readings of wind direction in any given geographic setting. Wind cools the body by increasing the amount of moisture evaporated at the skin’s surface. Some broad patterns of wind are evident during the four seasons of the year for an open, level site surrounding a two-story house located in the temperate zone:
• All sides of the house are exposed to wind at some time during the course of the year. These general patterns are further modified by the presence of mountain ranges and large water bodies. Wind is more variable on a daily basis than sun but does hold to some generalized patterns based on season and weather fronts. For example, Figure 3—27 illustrates how different locations of houses and vegetation on adjoining properties influence where wind is either concentrated or screened from a site. For example, wind originates mostly from the south and southwest during a warm front but shifts to the northwest following the passage of a cold front. The wind direction also responds to weather fronts. Figure 3-26
^ Typical wind patterns in the
і temperate zone. This is desired when air temperatures exceed the comfort range of 70 to 80°F. Wind accentuates the perception of cold air at these temperatures and creates what is commonly called “wind chill.” Similar phe­nomena occur for the house itself. These objectives apply both for outdoor spaces and for the house itself.