ID#2145 made on
EQc6.2 - Controllability of systems - thermal comfort
LEED BD+C: New Construction, LEED O+M: Existing Buildings, LEED ID+C: Commercial Interiors, LEED BD+C: Core and Shell, LEED BD+C: Schools
The project team is supplying individual desktop thermal units that provide supplemental warm or cool air according to the individual's desires. The units supplied will be Herman Miller's C2 System, a...
The project team is supplying individual desktop thermal units that provide supplemental warm or cool air according to the individual's desires. The units supplied will be Herman Miller's C2 System, and will be provided for at least 50% of building occupants in our project. In order to meet the intent EQc6.2, per the LEED-CI reference guide, to "provide a high level of thermal and ventilation control for individual occupants to promote the productivity, comfort and wellbeing of building occupants," the project team has implemented several thermal and ventilation control strategies. As part of the building design process, the office renovation project used the existing HVAC system to provide adequate airflow according to the requirements of ASHRAE Standard 62.1-2004. Additionally, the thermal comfort factors included in ASHRAE Standard 55-2004 were reviewed in the design phase. These factors included temperature, humidity, and radiant temperature. Finally, individual control over thermal comfort was included with the incorporation of the C2 System. As ASHRAE Standard 55-2004 indicates, individuals may desire temperatures +/-3 degrees Fahrenheit from the HVAC set point depending on clothing, activity levels or individual preference. In order to fulfill the credit requirement to provide at least 50% of occupants with individual control over temperature and ventilation, the project occupants were provided with the C2 System personal, portable, electronic climate control devices as part of the design strategy. Another option considered was to configure additional ducting, VAV boxes, and thermostat controls to extend the existing HVAC system, but this was determined by the project team to be less energy efficient, more costly to install and maintain, and less adaptable to individual comfort and changeable furniture configurations. In the reference guide and previous CIRs, it is stated that individual controls need be hardwired to the building system. The project team would like to suggest that projects be allowed to account for non-hardwired thermal units when pursuing EQc6.2, as is allowed in the requirements for EQc6.1. In the cases of both task lighting and thermal comfort, providing individual controls leads to increased occupant comfort and consequently improved satisfaction and productivity. The provision of personal controls also reduces occupants' reliance on building systems to meet their individual comfort needs. This clarification will allow project teams following the LEED for Commercial Interiors rating system to accommodate for individual occupant needs in instances where they have limited or no control over the existing building systems beyond their tenant space, as well as in situations where furniture configurations and occupant usage patterns make it advisable to give occupants more flexibility to reposition the units as needed. The project team has also invested in TuffLock padlocks, Herman Miller's standard recommendation for the C2 System. With addition of the security cable, the portable system can be tethered to a desktop unit. Additionally, the project team has created a program that will require that at least 50% of the tenant space occupants be provided a C2 System. The program will verify on a monthly basis that the units are accounted for. It is the purpose of the program to identify any lost or stolen C2 Systems. It is our opinion that the C2 System provides individual control over the comfort factors included in ASHRAE Standard 55-2004 while meeting the intent of credit EQ 6.2. We would ask for confirmation that this design solution meets the credit requirements.
The project team is asking whether providing non-hardwired thermal control units (i.e. desktop fans, heaters, or coolers) to at least 50% of the space occupants would meet the requirements of EQc6.2. The intent of this credit is to encourage project teams to design integrated controls that will allow for reaping the long term benefits of occupant satisfaction and productivity. The approach described above will be acceptable in tenant improvement of retrofit projects only if it can be shown clearly that the building ventilation system is incapable of allowing the level of controllability required by this credit. This provision is meant to accommodate Commercial Interiors projects, where the project team has limited or no control over the existing building systems beyond their tenant space. In all other cases, the project team is required to provide adequate controls integrated in the building ventilation design or operable windows, to show compliance with the requirements of this credit. Therefore the approach described above would not be acceptable for other rating systems. This ruling is consistent with previous CIR rulings. Applicable Internationally.
Related Addenda (Corrections & Interpretations)