Hey there! We've recently recived feedback on a laboratory/office CS project. The LEED Reviewer found isssue with our Outdoor air flow rates, specificially the fact that the outdoor airflow rate is higher in the baseline than the proposed. We are prohibited by code to recirculate air, and modeld both models as 100% ODA as per Addendum CN. It was our interpretation that the Laboratory spaces' outdoor air flow rate could be greater in the proposed given both lab systems are modeled as 100% OSA (to provide credit for lowering OSA per the credit description). We reached out to a LEED coach with our question and they insisted that the baseline OSA peak flow rate could not be greater than that of the proposed, even with exception d of Addendum CN.
I am thinking the coach didn't understand our question fully and are hoping to meet with them in the matter. I would be greaful to anyone who has experience with the addendum to let me know if the interpretation above is correct! I would love a sanity check before I try to convince the Coach of something that is worng! Cheers and thanks in advance!
Tyler Thumma
7GroupLEEDuser Expert
67 thumbs up
April 5, 2024 - 9:40 am
You are correct that the Baseline outdoor airflow can be higher than the Proposed when applying addendum cn. This would happen if the cooling loads drove the baseline total supply airflow requirements above that of the OA flow supplied in the Proposed case.