Section C406 Additional Efficiency Package Options
Buildings shall comply with one or more of the following:
- More efficient HVAC performance in accordance with Section C406.2.
- Reduced lighting power in accordance with Section C406.3.
- Enhanced lighting controls in accordance with Section C406.4.
- On-site supply of renewable energy in accordance with Section C406.5.
- Provision of a dedicated outdoor air system for certain HVAC equipment in accordance with Section C406.6.
- High-efficiency service water heating in accordance with Section C406.7.
- Enhanced envelope performance in accordance with Section C406.8.
- Reduced air infiltration in accordance with Section C406.9
Tenant spaces shall comply with Section C406.2, C406.3, C406.4, C406.6 or C406.7. Alternatively, tenant spaces shall comply with Section C406.5 where the entire building is in compliance.
Exception: Previously occupied tenant spaces that comply with this code in accordance with Section C501.
Interior lighting in the building shall have the following enhanced lighting controls that shall be located, scheduled and operated in accordance with Sections C405.2.1 through C405.2.3.
- Luminaires shall be configured for continuous dimming.
- Luminaires shall be addressed individually. Where individual addressability is not available for the luminaire class type, a controlled group of not more than four luminaries shall be allowed.
- Not more than eight luminaires shall be controlled together in a daylight zone.
- Fixtures shall be controlled through a digital control system that includes the following function:
- Control reconfiguration based on digital addressability.
- Load shedding.
- Individual user control of overhead general illumination in open offices.
- Occupancy sensors shall be capable of being reconfigured through the digital control system.
- Construction documents shall include submittal of a Sequence of Operations, including a specification outlining each of the functions in Item 4.
- Functional testing of lighting controls shall comply with Section C408.
The total minimum ratings of on-site renewable energy systems shall be one of the following:
- Not less than 1.71 Btu/h per square foot (5.4 W/m2) or 0.50 watts per square foot (5.4 W/m2) of conditioned floor area.
- Not less than 3 percent of the energy used within the building for building mechanical and service water heating equipment and lighting regulated in Chapter 4.
Buildings shall be of the following types to use this compliance method:
- Group R-1: Boarding houses, hotels or motels.
- Group I-2: Hospitals, psychiatric hospitals and nursing homes.
- Group A-2: Restaurants and banquet halls or buildings containing food preparation areas.
- Group F: Laundries.
- Group R-2.
- Group A-3: Health clubs and spas.
- Buildings showing a service hot water load of 10 percent or more of total building energy loads, as shown with an energy analysis as described in Section C407.
The building service water-heating system shall have one or more of the following that are sized to provide not less than 60 percent of the building's annual hot water requirements, or sized to provide 100 percent of the building's annual hot water requirements if the building shall otherwise comply with Section C403.9.5:
- Waste heat recovery from service hot water, heat-recovery chillers, building equipment, or process equipment.
- On-site renewable energy water-heating systems.
Air infiltration shall be verified by whole-building pressurization testing conducted in accordance with ASTM E779 or ASTM E1827 by an independent third party. The measured air-leakage rate of the building envelope shall not exceed 0.25 cfm/ft2 (2.0 L/s x m2) under a pressure differential of 0.3 inches water column (75 Pa), with the calculated surface area being the sum of the above- and below-grade building envelope. A report that includes the tested surface area, floor area, air by volume, stories above grade, and leakage rates shall be submitted to the code official and the building owner.
Exception: For buildings having over 250,000 square feet (25 000 m2) of conditioned floor area, air leakage testing need not be conducted on the whole building where testing is conducted on representative above-grade sections of the building. Tested areas shall total not less than 25 percent of the conditioned floor area and shall be tested in accordance with this section.