Is there a reliable way of doing a quality check or verification of a model’s LCA? How do you go about checking to avoid garbage in garbage out issues?
We have a model where we were initially estimating 30%+ carbon savings with respect to a baseline by switching most of the floors from steel deck with concrete topping for mass timber equivalents (still with concrete topping), but we are now estimating much lower ~6% savings. I’m trying to figure out how to best interrogate the inputs and outputs. Initially, it seems like we initially underestimated the foundations, the rest of the discrepancy, I can’t yet answer: I’m in progress.
Hey, Edwin! I was talking about this with some other people recently, and it came up that a QA/QC document might be fun to crowdsource. There are probably a few ways to structure this, but the way we approach this is as a list of questions when reviewing the model. But, I hate to say, we don’t really have a template. Maybe we can work toward this together?
Here’s a few to start, and I’d really love to hear about the checks being performed by other practitioners:
If it’s a mass timber structure, are takeoffs for steel connectors present?
These are sometimes absent from the Revit, but can be major contributors,
If there is rainscreen cladding, is the clip system reflected in the takeoffs?
Again, often missing from the model.
Does every quantity of reinforced concrete have a corresponding quantity of reinforcing bar or WWR? Is this a realistic quantity?
Tally will do this automatically, but OneClick won’t.
Does the area of floor and ceiling finishes roughly correspond to the floor area of the building? If not, can we explain why?
Does the vapor barrier takeoff roughly correspond to the opaque envelope area?
Are conveyance devices properly included?
Does the door count match what I’m seeing in the schedules?