Rating System

LEED O+M: Existing Buildings, LEED O+M: Existing Buildings

Rating System Version

v2 - LEED 2.0, v3 - LEED 2008

Inquiry

The existing building we are attempting to certify under LEED-EB does not have a mechanical OA ventilation system. The building has operable windows and all the permanently occupied spaces meet the requirements of ASHRAE 62.1-2004, subsection 5.1 for natural ventilation and therefore meet this prerequisite. But on the LEED-EB template, there are no tables available to document this information. The template requests "a letter and backup tabular information from a mechanical engineer". Will this be sufficient? When an email was sent to USGBC with this question, we received the following reply on 8/6/07: "The applicant may document the requirements of the pre-requisite as per section 5.1 of ASHRAE 62.1-2004. However, since there is no specific guidance in the LEED-EB 2.0 Reference Guide for supporting documentation of naturally ventilated buildings, the applicant should refer to the LEED-NC v2.2 Reference Guide page 292, Table 2 : "Sample Summary Calculations Used to Determine Outdoor Air Ventilation Rates - Naturally Ventilated" for supporting documentation guidance. Please follow this table for your documentation." Is it your recommendation that we use the table and the template from LEED-NC EQ Pre1 as supporting documentation as per USGBC staff\'s email?