EQ Credit 2: Increased Ventilation LEED-NC Credit: YES | UNSURE | NO Credit Intent Incorporate increased outdoor air ventilation to the building. This is believed to improve overall indoor air quality, thus bettering occupant comfort, well-being, and productivity. Feasibility If this credit is included in the design of the building and its ventilation system from an early stage, it appears that it could be obtained rather easily. The overall design of the HVAC system would change slightly from that required in Prerequisite 1. Due to the increased ventilation rates, however, an increase in energy (and therefore cost) would likely occur in the mechanical ventilation system. The benefits gained for indoor air quality are assumed to outweigh these economic drawbacks. In the case of natural ventilation, however, an increase in cost is unlikely. Stanford’s climate is ideal for natural ventilation with low humidity and generally mild temperatures throughout the year. The cool nights and mornings allow for many hours of possible natural ventilation in the warmer months. Increasing airflow from this particular ventilation source could be cost-effective, as it would replace the need for mechanical ventilation where it is implemented. Overall, increased ventilation is desirable because of the increase in indoor air quality. Since the GSB is an environment that requires comfortable spaces and aims for high levels of productivity, an opportunity for an increase in indoor air quality will most likely be pursued. Since the GSB will contain both mechanically and naturally ventilated spaces, requirements for both would have to be met. Mechanically ventilated spaces are required to have ventilation rates at least 30% above those required in Prerequisite 1. Naturally ventilated spaces require a bit more documentation and calculations to ensure that adequate ventilation is met in the spaces within the building. Analysis While it cannot be certain that this credit is met in the new GSB, it has been decided to use much natural ventilation in the structure. Early planning documents state that, “Natural ventilation will be a sole source or supplemental source of conditioning and ventilation where possible.”1 In areas ventilated by mechanical means, a displacement air system is to be implemented. Underfloor air distribution is planned for the entire ground floor, while the second and third floors incorporate an air displacement system and much natural ventilation. Natural ventilation is used is offices and other rooms along the perimeter of the building, while air displacement is planned for interior spaces. The only individual building relying entirely on mechanical systems is the Common Area, which uses an underfloor air distribution system. In the spaces that utilize natural ventilation, operable windows will be included. The faculty office building (indicated below) will contain a variety of systems on the second and third floors. The north face of the building will contain only natural ventilation through the use of operable windows and ceiling fans. The south, east, and west faces will contain operable windows for natural ventilation, as well as the possibility for use of an air displacement system for additional ventilation. A red or green light indicator will notify building users on these sides of the building when to open or close windows for optimal performance2. 1 “Pre-SD Mechanical Narrative,” April 30, 2007 accessed on the Coursework website 2 IbidEQ Credit 2: Increased Ventilation LEED-NC Credit: YES | UNSURE | NO Below is the proposed ventilation scheme for the second floor (third floor similar): Figure 4: Mechanical Schemes for Second Floor3 3 Figure accessed on Coursework website Faculty Office