Page 153 - The Engineering Guide to LEED-New Construction Sustainable Construction for Engineers

LEED W ater Ef ficiency 133

Exercises
2
1. You plan to plant 24,000 ft of area with vegetation on a site in Columbia, S.C.
A. You plan to use a typical sprinkler system. What is your expected TPWA for the following
combination of plantings?
2
- 8000 ft will be north of the planned building and will be mixed tree and shrub species
with average water needs, densely planted.
2
- 8000 ft will be average density, low-water-use lawn on a sloped area west of the building.
- The remaining will be a shrubbed landscape bed, with species of average water needs
and spaced around normally.
B. You then decide to try to get two points for LEED 2009 WE credit 1 by keeping all the
areas natural with the existing woods that require no irrigation except for the lawned area
mentioned. Will you meet the credit requirement with only these changes? You can assume
that the design in part A is a typical practice.
C. Is this also eligible for an RP point? (See Chap. 7.)
2
2. You plan to plant 24,000ft of area with vegetation on a site in East Hampton on Long Island, N.Y.

A. You plan to use a typical sprinkler system. What is your expected TPWA for the following
combination of plantings?
2
- 7000 ft will be north of the planned building and will be mixed tree and shrub species
with average water needs, densely planted.
2
- 9000 ft will be average density, low-water-use lawn on a sloped area west of the building.
- The remaining will be a shrubbed landscape bed, with species of average water needs
and spaced around normally.
B. You then decide to try to get two points for LEED 2009 WE credit 1 by keeping all the
areas natural with the existing woods that require no irrigation except for the lawned area
mentioned. Will you meet the credit requirement with only these changes? You can assume
that the design in part A is a typical practice.
C. Is this also eligible for an RP point? (See Chap. 7.)
3. You plan to plant 20,000 ft of area with vegetation on a site in San Francisco.
2
A. You plan to use a typical sprinkler system. What is your expected TPWA for the following
plantings?
2
- 7000 ft will be north of the planned building and will be mixed tree and shrub species
with average water needs, densely planted.
- 5000 ft will be average density, low-water-use lawn on a sloped area west of the
2
building.
- The remaining will be a shrubbed landscape bed, with species of high water needs and
the plants spaced around normally.
B. You then decide to try to get two points for LEED 2009 WE credit 1 by using low-water-need
plants and a drip irrigation system in the landscape bed. You can also extend the modified
landscape bed into the lawn area. How much of the lawn area would need to be converted
to obtain this credit? You can assume that the design in part A is a typical practice.
C. Is this also eligible for an RP point? (See Chap. 7.)
4. Your client really would like an expansive, thick lawn in front of her new office building and
would like to obtain at least two WEc1 points by using rainwater harvesting. The building is in
Austin, TX. The building could be oriented with the front façade facing either north or west. You
are deciding between a low-water and an average water-need lawn. Determine how much water
is needed to irrigate the lawn with a sprinkler system per square foot for the four possible options
for the month of July.