CO2 sensors can 1) measure the indoor concentrations of CO2 and compare them against ASHRAE 62.1-2004 limits or, 2) measure the indoor concentrations of CO2 and compare them against outdoor CO2 concentrations. If you choose the second option, you will need to install outdoor CO2 monitors as well.
Outdoor air can contain contaminants that lead to unhealthy working or living conditions. You may need to assess the quality of the local outdoor air before bringing it indoors. HHigh efficiency MERV filters (13 or higher) are one solution to treating poor-quality outdoor air before supplying it to the indoors.
Conduct a preliminary cost-benefit analysis to determine the first cost and life cycle payback. Most teams use LEED point thresholds as a way to frame the analysis. For example, what is the cost and the payback of meeting the 2.5% threshold?
The default leakage rate used in the credit form calculator is 2%, and the end-of-life refrigerant loss value should be 10%. If your project has equipment with different leakage rates, those values can be used instead.
Establish preliminary goals for water-use reduction. Consider setting water-reduction goals higher than the 30% reduction required by this credit, and aim for a reduction greater than 40% or higher for exemplary performance under IDc1. You are likely to need rainwater or graywater
Specify high-quality equipment with a dependably long lifespan. That way leakage is minimized at those times that carry the greatest risks; when the equipment is being installed or decommissioned. (For information about the service life of different types of HVAC equipment, see the 2004 ASHRAE Applications Handbook—HVAC Applications. See Resources.)
For companies that provide vehicles for employee use, consider “greening your fleet” by purchasing vehicles qualified as low-emitting and fuel-efficient. Project teams should carefully consider available technologies and different fuel sources before purchasing vehicles.
Calculating irrigation water use is not required for this credit; however, understanding how indoor water use compares to outdoor water use can help you gauge where to focus your reduction efforts for the greatest benefit. Some water-saving strategies address both indoor and outdoor water needs holistically. For example, if you treat your wastewater onsite, you can use the treated water to irrigate your landscape as well as to flush toilets.
