Rating System

LEED BD+C: New Construction, LEED BD+C: Core and Shell, LEED BD+C: Schools

Rating System Version

v3 - LEED 2009, v2 - Schools 2007, v2 - LEED 2.2

Inquiry

We seek approval of the following energy analysis approach for a project registered under LEED-NC v2.2, after June 26, 2007. The project is a ballpark located in Climate Zone 5A. A majority of the concession stands and restrooms located on the concourses will only be used for ballgames from April through September. Traditionally, space unit heaters are installed for freeze protection of the plumbing systems and building finishes during unoccupied periods. These unit heaters would have a heating output between 3.4 Btu/h ft2 and the maximum allowance of 15 Btu/h ft2 listed in Table 3.1 of ASHRAE/IESNA Standard 90.1-2004, so the spaces would technically be considered semiheated. The spaces would be maintained at a minimum setpoint of 45 degrees F to ensure that none of the pipes freeze. We are considering implementing an energy conserving operational procedure. The plumbing systems would be drained down during the off-season from October through March when freeze potential exists. This practice requires special design consideration for ease of the drain down procedure. The concession stands and restrooms would require no space heating equipment, thereby eliminating space heating energy. The drain down practice requires special effort from building operations staff, and we believe that a commitment to such effort warrants consideration in the energy analysis. The energy savings are quantifiable and provide an environmental benefit. The drain down practice allows elimination of additional insulation and building materials that also provides an environmental benefit. Therefore, we propose to classify these concession stand and restrooms located on the concourses as semiheated spaces. The baseline insulation would be modeled as semiheated; the baseline heating setpoint would be modeled at 45 degrees F. The proposed spaces would be modeled as unconditioned.