While reflective roofs, or “cool roof” systems, can save energy by reducing cooling loads, a planted roof can provide additional benefits, such as managing stormwater and providing greenspace and habitat. Plant selection should require no or minimal supplemental water. If supplemental water is required, consider alternative water sources for irrigation. While making changes to the roof, consider installing a solar thermal hot water system, which can yield significant energy savings. Save more on water heating costs by heating less water: high-efficiency plumbing fixtures, like low-flow showerheads, toilets and urinals, and high-efficiency faucets with sensor controls, save both energy and water. The reduced demand at the fixture paired with the free heat from the sun may enable the installation of a smaller boiler and pumps, saving on both first costs and operating costs.

More than eight percent of total building energy consumption typically goes to heating, treating, and pumping water. Save on water heating costs by heating less water: high-efficiency plumbing fixtures, like low-flow showerheads and high-efficiency faucets with sensor controls, save both energy and water. A well-insulated and properly sized piping system (with minimal turns and direct paths) minimizes the loss of heat and energy during delivery. Together these strategies may enable the installation of a smaller boiler and pumps, saving on both first costs and operating costs.

For system and fixture upgrades, consider an Energy Savings Performance Contract (ESPC). Learn more about how to use ESPCs to mitigate the costs of energy-saving upgrades.

Bundling water-efficient plumbing fixtures and landscaping with alternative water sources can lead to significant savings. First, reduce overall water consumption with high-efficiency plumbing fixtures, like low-flow showerheads and high-efficiency faucets with sensor controls, and landscaping that requires no or minimal irrigation. Next, further reduce the demand for potable water by replacing potable water in systems such as irrigation and cooling towers with alternative water sources such as captured rainwater or condensate. See DOE's Best Management Practices for more examples.

Vegetation that has minimal demand for water (xeriscaping), as appropriate for site conditions and climate, as well as reduced need for fertilizers and pesticides, can simultaneously reduce the amount of landscape organic waste generated. Recovering landscape trimmings, for use as compost or mulch, also reduces the need for irrigation and conserves water.

Sustainable Sites Initiative. The Sustainable Sites Initiative: Guidelines and Performance Benchmarks 2009.

Guidance for Federal Agencies on Sustainable Practices for Designed Landscapes

SFTool Water Whole Building System - Resources Impact

Human behavior can contribute to system efficiencies and implementing an ongoing occupant education program can be the most cost-effective means of reducing water consumption. Green Teams can advance these efforts by educating fellow occupants and promoting sustainable practices. Obtaining the active participation of building occupants coupled with high efficiency plumbing fixtures, like low-flow showerheads, toilets and urinals, and high-efficiency faucets with sensor controls, can save both energy and water. Clearly communicate water consumption goals, meter water use, and share water consumption data with occupants. Provide a means for occupants to report leaks and other issues so corrective action can be taken.

Building automation consists of a computer-based system with integrated measurement sensors and control devices for components such as HVAC equipment, lighting, and renewable energy systems. Building Automation Systems (BAS) are a common form of energy management and information system (EMIS). Monitoring and controlling building systems allows building owners to identify opportunities for improved performance by tracking energy and water use, ventilation and other elements of IEQ, security and other operations. Investing in a BAS can realize significant savings:

• Consider synergies among building systems.
• Employ ongoing commissioning practices to ensure building systems are properly calibrated and maintained over their lifespan.
• Use data to address areas of concern.

Building automation is interrelated with energy efficiency, water efficiency, ongoing commissioning, systems level metering and lighting control. Consider these strategies and other cost-effective upgrades:

• Smart sensors and valves can automate water usage, detect issues such as leaks, and prevent damage from overflows and leaks by restricting the flow of water when issues are detected.
• Automated irrigation systems use sensors and weather data to determine soil moisture levels and, when water is needed, the appropriate time to irrigate and the appropriate amount of water to deliver. This can significantly reduce the amount of water used to maintain a healthy landscape.