s, west- and south-facing window shading, blower door and duct testing, an HVAC commissioning plan, mechanical equipment efficiencies, renewables, and much more. Many of the efficiency electives affect a project’s Title 24 calculation, letting you kill two birds with one stone. For instance, a good passive-solar design can radically improve your Title 24 score. The same is true for duct and blower door testing. By selecting these types of measures, you can satisfy both the Tier I percentage threshold and the Energy Efficiency elective requirements. You can meet the Water Efficiency elective requirements by reducing potable irrigation water use, rainwater capture, and graywater and recycled-water systems. Material Conservation electives include a variety of framing efficiency measures, low-maintenance materials, and moisture management measures. Environmental Quality electives are limited to meeting stricter formaldehyde requirements, greater than MERV 6 filters, and having no direct-vent appliances in conditioned space.
Tier II takes selected Tier I electives and makes them mandatory. In addition, Tier II also requires more electives than Tier I, from what is now a smaller pool, since some former electives are now prerequisites. Some of the Tier II requirements, summarized in Table 2, are similar to Tier I with higher thresholds; others are brand-new. The CalGreen reference guide warns that it’s difficult to achieve Tier II and suggests that local jurisdictions think carefully before making it mandatory.
In Planning and Design, in order to reach Tier II, you have to protect the topsoil (as required for Tier I), plus delineate the construction area with fencing or flags to protect it from damage by machinery and other construction activities. You also have to have at least 30% permeable hardscape (instead of 20% for Tier I) and cool-roof specifications that are more stringent than those for Tier I. For Energy Efficiency, you have to exceed Title 24’s baseline by 30% instead of 15%. In the Water Efficiency category, you have to meet the Tier I kitchen faucet 1.5 gpm requirement, plus install an Energy Star dishwasher that uses no more than 5.8 gallons per cycle. For outdoor water use, you have to reduce potable water use by at least 40% instead of 35%. Tier II Material Conservation requires that you reduce cement use by 25% instead of 20%, increase recycled material use by 15% by value, and reduce construction waste by at least 75% instead of Tier I’s 65%. For Environmental Quality, 90% of the resilient flooring must be low VOC, and insulation must comply with Collaborative for High Performance Schools (CHPS) standards and have no added formaldehyde.
The Tier II electives are all the code provisions that remain after meeting all the mandatory items and the Tier I and Tier II prerequisites. In order to complete a Tier II certification, you need to include the number of electives shown in Table 4: Planning and Design (4), Energy Efficiency (6), Water Efficiency (2), Material Conservation (4), and Environmental Quality (2). If your project manages to do all these things, you should have a pretty darn green building.
Overall, CalGreen seems to be both relatively green and flexible. Code jurisdictions can craft programs to suit their local requirements, and builders have multiple ways to comply without running up too many heavy expenses. Interestingly, many of the CalGreen provisions are similar to LEED for Homes provisions but not as stringent. Both systems track compliance with a prescriptive checklist and performance-based energy efficiency thresholds. What’s missing, in the Energy Efficiency category for both systems, is a requirement to track a building’s energy use after occupancy. This is a fairly recent, and not unfair, criticism of the various LEED rating systems. There’s no point in building better buildings if the only proof we have of their quality is the output from a modeling program or items on a prescriptive checklist.
Some of the CalGreen documentation requirements may be difficult to meet, but most of the prov