California has long been known as an energy-conservation pioneer. To lead the way on electrical issues, the state uses a set of rules known as Title 24, Part 6, which is updated every three years. The current rules became mandatory for any project seeking a permit after July 1, 2014.
Where it was
Title 24, Part 6, began in 1974 with the passage of the Warren-Alquist Act, which established the California Energy Commission and gave it the authority to “prescribe, by regulation, lighting, insulation, climate control systems, and other building design and construction standards which increase the efficient use of energy.”
The first set of energy-efficiency standards became effective in 1978. As an estimator in California, the following things started appearing on the plans I was bidding.
First, it was the calculations for watts-per-square-foot allowances, which did not affect the estimator. The calculations only took part of a plan sheet.
The next change was dual-level switching, which required most areas to feature controls that could turn a percentage of the lights off. This rule made plans a little more complex because we had to carry two switch legs throughout the circuit.
Then came motion sensors, which were a new technology at the time. I started seeing wall-switch versions in bathrooms and offices. In larger areas, ceiling-mounted versions were used.
Soon after that, there were daylight sensors near windows and skylights in rooms 2,500 square feet and larger. These sensors controlled a room’s light levels by dimming fixtures when they sensed enough daylight entering the space. Of course, such sensors required more wiring and more expensive fixtures, making the estimator’s job a little harder.
Where it is
The 2013 version of Title 24 made some major changes. For example, daylight controls are now required for areas with loads of 120 watts (W) or more in a daylighting zone. The 2013 version introduced mandatory receptacle switching, requiring a controlled receptacle within 6 feet of every noncontrolled, always-on receptacle in offices and some other areas. The controlled receptacles must be switched off if the area is not occupied. Finally, the demand-shed reduction now requires all nonresidential buildings 10,000 square feet and larger to be able to respond to a signal and cut lighting power at least 15 percent below maximum.
Another change dealt with switching levels. The new rules require fluorescent fixtures more than 13W to have switching levels of 20–40 percent, 50–70 percent and 80–85 percent in any space larger than 100 square feet, using greater than 0.5W per square foot. This requirement is almost a mandate for a dimming system, because it is very difficult to accomplish with switching. LED fixtures must be continuously dimmable between 100–10 percent.
These changes affect cost, complexity and time required to estimate a project. The lighting fixtures are more expensive because only LED fixtures can meet the watts-per-square-foot restrictions. The changes necessitate expensive, networked control systems, which require more wiring and additional training, expertise and commissioning by factory representatives. These new control requirements are a boon to the manufacturers, an appreciable expense to the owner and a nightmare for the estimator. In keeping with the trend of engineers turning out poor documents, these new Title 24 requirements have created another opportunity for engineers to furnish incomplete designs.
Where it’s going
Of course, the changes keep coming. The 2016 Title 24 changes should come into effect on Jan. 1, 2017. This version appears to have more changes for residential than commercial buildings. A significant change for residential is, with few exceptions, only high-efficacy light fixtures can be used. On the commercial side, there were complaints about previous requirements to upgrade the lighting control systems if you wanted to upgrade the lighting fixtures in a building. The added expense of the control system stopped many of these projects, which prevented the energy-use reduction that was possible by just upgrading the lighting fixtures. The 2016 Title 24 appears to back off the control requirement to some extent.
A possible simplification to the control wiring requirements is in the works: wireless. Many control manufacturers are developing wireless versions of their systems. However, while simplifying control system wiring, the expertise required to get the system running could significantly increase.
Since many states follow California’s lead, you may soon see some of these requirements on your projects.
Editor's note: Click here for part 2.