Trees and vegetation shade buildings and surfaces, while water evaporating through their leaves lowers nearby air temperatures.

Shaded walls and surfaces may be 11–25°C (20–45°F) cooler than unshaded surfaces. Temperatures under a canopy of shade trees may be reduced 1–5°C (2–9°F) compared to open terrain, and 11–17°C (20–30°F) compared to parking lots.

Locate:

  • Trees on the east, west, southeast, and southwest sides of a building (east, west, northeast, and northwest in southern latitudes).
  • Ground cover and shrubs around buildings to lower air temperatures and reduce reflected sunlight.
  • Trees in courtyards, parking areas, and adjacent to walkways.

Vegetated pergolas and trees with a high canopy provide shade and allow in beneficial winds. In climates with cold winters, locate trees away from the wall facing the equator a minimum distance of twice the height of tree.