Sustainable Facilities Tool General Services Administration

Planted roofs have synergistic benefits that result in energy saving and stormwater management; they are an attractive alternative to traditional roofing surfaces.  Planted roofs provide excellent insulation that reduce heat loss/gain from the building, filter and slow down stormwater from the site, and can beautify the workspace for occupants.  When selecting plants for planted roofs, make sure that there will be little requirement for supplemental water.  If supplemental water is required, consider collecting alternate water for irrigation.

While making changes to the roof, consider installing a solar hot water heating system. Solar hot water heaters, common in both commercial and residential settings, can save significantly on energy bills and frequently have a quicker payback period than photovoltaic panels. An even better way to save on water heating costs is to heat less water: high efficiency showerheads and faucets save both energy and water. The reduced demand at the fixture paired with the free heat from the sun may allow you to buy a smaller boiler and pumps, saving on both first costs and operating costs.

Retrofitting all components at once can be cost prohibitive, but bundling water-efficient fixtures with alternate water harvesting systems and landscape redesign can lead to significant savings. Optimizing the water system as a whole leads to the greatest reduction in potable water consumption and lead to synergies that can help reduce project scope. The first goal when optimizing the system is to reduce the demand for potable water by implementing water efficient equipment and landscape that requires little supplemental water.  With reduced potable demand, water captured in alternate water harvesting systems can be stretched further or downsized.  See DOE's Best Management Practices case studies for an example.

A sustainable landscape design and maintenance plan can reduce water consumption and waste generation. Planting vegetation that has low demand for water (xeriscaping), as appropriate for site conditions and climate, can simultaneously reduce the amount of landscape organic waste disposed. Recovering landscape trimmings, for use as compost or mulch, reduces the need for irrigation and conserves water. These sustainable landscape design and management practices have the added benefit of saving money through reduced water consumption, reduced waste disposal, reduced need for fertilizers and pesticides, and reduced labor for landscape maintenance.

Sustainable Sites

Guidance for Federal Agenceis on Sustainable Practices for Designed Landscapes

SFTool Water Whole Building System - Resources Impact

Some water system components, when bundled together, can significantly reduce overall building energy consumption as over eight percent of total energy goes to heating, treating, and pumping water. High efficiency faucets and showerheads reduce the quantity of water that need to be heated. A well-insulated and properly sized piping system (with minimal turns and direct paths) assures the energy that goes to heating the water is not lost during delivery. Having less water to heat allows for the purchase of a smaller boiler system, saving both money in energy utility bills and mechanical equipment operations costs.

Since energy conservation is a priority, these fixture upgrades can be integrated into an Energy Savings Performance Contract (ESPC). Learn more on how to use ESPCs to mitigate the costs of energy-saving upgrades.

Implementing an occupant educational awareness program and malfunctioning/reporting hotline can be the most cost-effective alternative to reducing overall water consumption in the office. Human behavior can attribute to system efficiencies. Obtaining the active participation of building occupants coupled with high efficiency faucets, toilets, and urinals can save a measurable amount of water. Central drinking water treatment and chilling systems may reduce the energy needed for water cooling when compared to many independent water coolers throughout the building.