This Credit Interpretation Request is being submitted in order to establish further clarification on an alternate method(s) of compliance of the Prerequisite for Minimum Acoustical Performance. We are most interested in clarifying the sound transmission class (STC) for roof construction over core learning spaces. We have reviewed materials outlined in the 23 April 2008 PIEACP and the 13 May 2008 Errata for the 23 April 2008 PIEACP, as well as the previously submitted CIRs. The LEED certification process is for an addition to an existing suburban high school, although renovation is also in the project scope of work. The new portions of the school will include classrooms on the first and second floors, as well as Music Rooms and a TV Studio. A two-story Auditorium with a fly tower will extend above the roof height of the second level of classrooms. The site location is beyond a half mile of any major sound producing infrastructure, e.g. train lines, major highways, airport flight paths or other major potential exterior noise sources. The existing school is situated in a fully developed residential neighborhood set off by a number of blocks from the nearest commercial route. The surrounding area is highly unlikely to include any future additions or redevelopments. We believe these qualifications follow the Option 2 Alternative Compliance Method for Sound Transmission requirement as outlined in the 4/23/2008 Errata. The current design also includes interior ceiling treatment with an NRC of 0.70 or higher for all classroom and other core learning spaces as outlined in the Errata issued 4/23/08. The planned exterior wall and glazing construction will meet the original LEED for Schools Prerequisite for Minimum Acoustical Performance (EQpreq3) requirements. The roof construction over core learning spaces is currently designed to achieve an STC 40 minimum rating. We believe this rating for roof construction follows the CIR Ruling dated 19 December 2007, and is applicable to our site due to its inherit low sound qualities now and in the future. For the Music Rooms and TV Studio spaces, as well as the Auditorium and its fly area, the roof construction and exterior walls are designed to exceed the LEED requirements of the original prerequisite. We were concerned about the high potential of internal sound generation and the sensitivity of these spaces to the intrusion of external noise. We have included the acoustic best practices for interior finish and background noise requirements for these type spaces, including acoustically isolating them from the surrounding classrooms and learning spaces. We feel that due to their special nature of use, it necessitated designing these spaces to exceed the requirements of the original prerequisite and surpass the threshold of the first enhanced acoustical credit to provide the best sound control for the building users in and surrounding these spaces. Please indicate whether or not this methodology is sufficient for alternative compliance(s) with this Prerequisite. Is it possible to follow the original prerequisite requirements for certain portions of the construction while adhering to the alternative requirements from PIEACP interpretation for other portions of the building design? In addition, is it possible to use the 23 April 2008 PIEACP Alternate Compliance Method for meeting the Background Noise Level Requirement to show compliance for the Enhanced Acoustical Performance Credit (EQc9)?