Adding floors to existing building, plus addition

I think counting the square footage of the added floors, so that the project qualifies for the credit, is entirely within the objective/intent of this credit. Just to be clear, the 2 new floors are entirely contained within the original volume of the existing building (like mezzanines), not added to the top of the building. There are no new structural walls or roof. Any added structural flooring would not be included in the calculations. The entire church and all its structural elements are being reused. But if we are only allowed to count the original ground floor square footage of the church, then the new addition and connector appear to be much, much larger by comparison, which they are not -- they are actually about equivalent in height and final square footage. We will be attemtping this credit via the "alternative compliance pathway" approach, and I will post an update regarding our success.

Follow up -- We received this response from GBCI: "Thank you for contacting LEED Support regarding new floors inserted into an existing building. For EAc1, this is clearly new space but inside an existing envelope. For the purpose of determining new versus existing/renovated floor area, because the new floors are contained within the existing church building, it is reasonable to consider this area as existing/renovated. This issue does not affect MRc1. This credit only considers the amount of an existing system that will be kept. For example, if all existing exterior walls will be kept, than the percentage for that element is 100% regardless of what new is added. The only roadblock could be the existing/new proportion limitation noted at the bottom of page 347 in the 2009 LEED Reference Guide for Green Building Design & Construction, June 2010 edition." So the "roadblock" was acknowledged, but not really resolved. We are going to try to be consistent with EAp2/c1, and call this "existing/renovated space."

Hi Deborah - We have actually un-attempted this credit. I think we would have been successful, except for a new basement level that is equivalent to the footprint of BOTH the existing building and addition. Once that was added to new square footage, we clearly exceeded 2 times the existing building. This is unfortunate because the owner and design put a LOT of thought, efoort, and cost to move and preserve the existing historic building, and they are basically receiving zero credit for this (in LEED terms) -- it's not even enough material to help with an ID point under MRc2! Oh well, that's not why they did it, but it would have been nice to claim something for it. Sorry to not be more help.