Landscaping for Energy Efficiency
Mike Sperber of Nature’s Guardian Inc.
Did you know that proper landscape design can lower your energy bills?
Solar heat absorbed through windows and roofs can increase cooling costs, and incorporating shade from landscaping elements can help reduce this solar heat gain.
Trees are available in the appropriate sizes, densities, and shapes for almost any shade application. To block solar heat in the summer but let much of it in during the winter, use deciduous trees. To provide continuous shade or to block heavy winds, use dense evergreen trees or shrubs.
Deciduous trees with high, spreading crowns (i.e., leaves and branches) can be planted to the south of your home to provide maximum summertime roof shading. Trees with crowns lower to the ground are more appropriate to the west, where shade is needed from lower afternoon sun angles. Trees should not be planted on the southern sides of solar-heated homes in cold climates, because the branches of these deciduous trees will block some winter sun.
Although a slow-growing tree may require many years of growth before it shades your roof, it will generally live longer than a fast-growing tree. Also, because slow-growing trees often have deeper roots and stronger branches, they are less prone to breakage by windstorms or heavy snow loads. Slow-growing trees can also be more drought resistant than fast-growing trees.
Plant trees far enough away from the home so that when they mature, their root systems do not damage the foundation and branches do not damage the roof.
Trees, shrubs, and groundcover plants can also shade the ground and pavement around the home. This reduces heat radiation and cools the air before it reaches your home’s walls and windows. Use a large bush or row of shrubs to shade a patio or driveway. Plant a hedge to shade a sidewalk. Build a trellis for climbing vines to shade a patio area.
Vines can also shade walls during their first growing season. A lattice or trellis with climbing vines, or a planter box with trailing vines, shades the home’s perimeter while admitting cooling breezes to the shaded area.
Shrubs planted close to the house will fill in rapidly and begin shading walls and windows within a few years. However, avoid allowing dense foliage to grow immediately next to a home where wetness and continual humidity could cause problems. Well-landscaped homes in wet areas allow winds to flow around the home, keeping the home and its surrounding soil reasonably dry.
Information above obtained from www.energy.gov