Editing Energy-efficient landscaping (section)

==== Benefits ====
Reducing building energy consumption by increasing the roof insulation: In total energy consumption reduction, green roof would have the best performance relative to a bare roof in a colder climate, which require nighttime heating. The reduction in heating load of the building increase as the soil depth of the green roof increase, though an increased soil depth would mean heavier roof. On the other hand, if a building is cooling-dominated, [[leaf area index]] is more important. In peak energy consumption reduction, green roof also has a notable effect, and the leaf area index and soil depth are both positively related to its performance.<ref>{{Cite journal|last1=Sailor|first1=David J.|last2=Elley|first2=Timothy B.|last3=Gibson|first3=Max|date=2011-09-13|title=Exploring the building energy impacts of green roof design decisions – a modeling study of buildings in four distinct climates|url=http://dx.doi.org/10.1177/1744259111420076|journal=Journal of Building Physics|volume=35|issue=4|pages=372–391|doi=10.1177/1744259111420076|s2cid=108512300|issn=1744-2591}}</ref>

Rainwater retention and [[evapotranspiration]]: 3-4 inches of soil can retain about 1 inch of rainwater. That is about 75% of [[precipitation]] in most areas in United States.<ref>{{Cite web|last=Johnson|first=Peter|date=Sep 2008|title=Green Roof Performance Measures|url=https://doee.dc.gov/sites/default/files/dc/sites/ddoe/service_content/attachments/D.%20Green_Roof_Performance-05-04-2009.pdf}}</ref> By retaining the rainwater in soil, the water would not become runoff, instead they would result in evapotranspiration.