I am working on a residential redevelopment in a mature inner suburb. Previously the site was a low density residential neighbourhood.
In the explanation of GIB c4 the Reference Guide notes that "projects with no new or existing landscape irrigation requirements automatically meet the credit requirements."
Previously the landscape of the project was mainly lawn and some trees (as would be typical of a low density suburb). We are proposing a slightly higher density of development, a mix of single detached houses and semi-detached townhouses.
At this point there is no way to know what the landscaping will be for the single detached lots (people can do with them whatever they want when they buy them). However we know the landscape will generally be similar to the pre-existing condition in terms of landscape irrigation requirements - a mix of trees and lawn. In fact, there will be less irrigation required as we have more hard surface. We will not be providing any irrigation infrastructure such as sprinklers in the public park or townhouses.
Am I correct in my understanding of the intent of the credit? The documentation requirements seem to want an imaginary baseline condition, rather than the pre-existing condition. We propose to use the pre-existing condition as the baseline. Is that a correct interpretation?
Eliot Allen
LEED AP-ND, PrincipalCriterion Planners
LEEDuser Expert
303 thumbs up
August 6, 2012 - 10:31 am
Tyler, you're correct that the credit wants an 'imgainery' or good faith estimate of a baseline from which the percent water savings is calculated. But you shouldn't use your pre-existing condition because you describe the new project as having landscape design changes, including less irrigated area. So your baseline should be an estimate of the new design's water needs using reasonable assumptions for landscaping, and other variables itemized in the ND reference guide.
Eliot