LEED-BD+C Hospitality - MRc5 Option 2 for a modular building.

Hi Susan!  Without the direct support and information from the manufacturer on their waste generation/reduction, I am not sure how you would calculate the total waste reduction.  I believe the intent of this pathway within LEED assumes that waste tracking would be available or at least more available than you have indicated from the manufacturer, since it is about reduction at the source and not at the site.  Are you able to dive in a little deeper with the manufacturer to see what information you can get from their facility?  Since the calculation just requires the total project area and total (lbs) of construction and demolition waste, I have not seen a dedicated calculator from USGBC for this.  The credit requirement thresholds did change between v4 and v4.1, shifting the v4 requirement of achieving no more than 2.5 lbs/SF to 7.5 lbs/SF for new construction facilities that are not warehouses or distribution centers.  Again, I think the intent behind this option is aimed at pushing manufacturer's to improve their practices, so if you can continue the conversation with the manufacturer and work with someone on obtaining any information they have, then perhaps some conclusions can be made relative to the assembly they are manufacturing for your project.

My understanding of Option 2 is that it is only about waste generated on site. The reference guide states that strategies to reduce waste on site include prefabrication and modular construction. I would assume you don't need to account for waste generated by the modular guestroom manufacturer off-site, just like you don't account for any other waste generated by manufacturers. One of my current projects special ordered 8' 2" sheets of gypsum so we don't have to cut on site, but I assume we wouldn't have to track down the waste generated by the gypsum manufacturer. We don't track the waste from any of the trades that do prefab and I don't see why modular would be any different.

Thanks Nathan.  You are correct.  My post needs to be edited to better clarify and correct my response.  While I do believe there is validity in pushing manufacturers on their waste processes and reduction, LEED credit requirements are specific to onsite generation.  The idea of using prefab elements would be relating to your overall waste generated and leaving the site to be less.  In both Options, waste/diversion is still obtained from the waste hauler, however, in Option 2 project use the total waste generated (regardless of whether diverted or not) and divide that by the project's gross floor area.  

Susan - With Nathan's response, which is correct in this case for Option 2, you shouldn't require any information on the waste generated directly from the manufacturer. Just use your total waste generated onsite for your project to calculate your waste reduction.