Page 229 - Green Building Through Integrated Design

WATER EFFICIENCY QUESTIONS 205

Water Efficiency Questions

As we pointed out in the previous chapter, water conservation in buildings will undoubt-
edly assume even greater importance in the years ahead. As a result, during design devel-
opment, we need to plan for a detailed systems approach to water efficiency.

1 Will ultra-water-conserving plumbing fixtures be acceptable to local officials (and
possibly local plumbing unions)? Can we reuse gray water or other nonpotable
water generated in the building?
2 Are there still other ways to reduce the water demand for landscaping, for exam-
ple, by changing the aesthetic experience of the plantings?
3 Will landscaping provide shade for at least 50 percent of all impervious surfaces
within 5 years, measured at solar noon at the summer solstice?
4 Will landscaping provide food and shelter for indigenous wildlife, by using native
or adapted plantings?
5 If landscaping needs time for irrigation to get established, can we provide for a
temporary (dry season) irrigation system that can be removed within 1 year?
6 If we need irrigation for this project, have we used high-efficiency irrigation con-
trols to reduce such use by at least 50 percent over conventional means?
7 For the hardscape areas, have we provided high-albedo reflective surfaces such as
light-colored concrete, so that there is less heat buildup in the local microclimate?
8 For parking lots, have we investigated the use of pervious paving systems (such
as open-grid pavement systems) to reduce runoff? Would there be any time of
maintenance that could reduce the effectiveness of pervious pavement, such as
sanding of parking lots during winter?
9 Can we store rainwater or graywater cost-effectively on the site? Will the costs for
site work for underground vaults or tanks increase significantly?
10 Have we discussed our water recycling or reuse systems with local code officials
to get their feedback at an early stage?
11 If we’re using rainwater storage, have we found a good location for the tank(s) or
storage vaults?
12 Has equipment for treating harvested rainwater been sized and selected (possibili-
ties include UV treatment, prefilters, piping connection to domestic water system)?

PLATINUM PROJECT PROFILE
The Ranch House at Del Sur, San Diego, California
The Ranch House at Del Sur is a 3000-square-feet welcome center for San
Diego’s Del Sur neighborhood. Completed in June of 2006, it serves as a com-
munity center and sales office. The Ranch House was designed to reduce energy
use by 45 percent (excluding office equipment). A 5.7-kW roof-integrated solar
electric system supplies more than one-third the facility’s energy demand; overall
energy savings are nearly 65 percent. Efficient plumbing fixtures have reduced