Principle: The residential site should conform to the regional context.

Every geographic location has its own unique ecology collectively established by cli­mate, topography, geology, soil, vegetation, and fauna. These interdependent natural factors along with human-imposed territories such as municipalities, townships, or counties define a region. The size of a region varies from one location to another, though it is typically accessible within a one – to two-hour drive. However large, each region is distinguished by its own particular physical character and environment. Sustainable design recognizes the special qualities of each region and adapts site or­ganization, materials, construction techniques, and overall visual quality to fit them.

Regional Climate Fit

Each region is distinguished by a set of climatic factors, including temperature ranges and cycles, precipitation amount and patterns, wind direction and strength, seasonal sun angles, the number of sunny days, and humidity. These factors should affect the size, location, and orientation of all outdoor spaces and use areas on the residential site. What is appropriate in one region is often not suitable in another. For example, an outdoor sitting space is best placed on the south side of a residence in New England to benefit from the warmth of the sun, and on the east or north side of a house in New Mexico to take advantage of the shade (also see “Study Sun and Shadow Patterns” in “Natural Events and Cycles” in this chapter).

The regional climate should affect what construction materials and techniques are employed (also see “Use Regional Materials” in this section). Wood, for example, works well as an exterior material in temperate climates but is not practical in hot, arid climates where intense sun rapidly deteriorates it. How materials are joined, are finished, or extend into the ground should similarly be determined by regional cli­mate conditions. All structures and pavement areas must be detailed with frost in mind in cold regions, whereas there is no need for this in warm climatic regions.

How much water is used and where on the residential site should also be deter­mined by the region’s climate. Ideally, a landscape should be designed to use only as much water as is available from natural precipitation and augmented, if at all, with ir­rigation in selected areas (also see “Conserve Water” in “Natural Events and Cycles” in this chapter). In addition, plants should be selected based on temperature ranges (har­diness zones), precipitation amounts, and precipitation cycles.