We haven’t had a project use carbon cure yet. We’ve been relying on getting high scm mixes that are (on average) 30% below the NRMCA regional average, which has been relatively easy for most of our projects - my personal guess is that the regions are large and working in more metropolitan areas gives us a leg up on the larger regions, so the baseline is (as always) questionable.
However, we did have a project where Aureus Earth was testing out selling offsets for the construction of mass timber buildings. My understanding is that the narrative was that this was a pilot project to prove the funding mechanism and not considered a proper offset. I was only involved in the LCAs which we were doing for our own internal discussions, and in this case, we did take credit for using mass timber.
The accounting side is murky. For our internal numbers, I think we can and should count the reductions in our LCAs - we’re designing using lower carbon materials and if we want to enact actual change in our designs, we should aim for the lowest carbon options. We’re also doing this just to judge our work against ourselves, not to report officially. In a related discussion, I was just asked about Nucor’s EPD including lower emissions through a PPA agreement. in this case, the EPD includes both with the PPA offset and without. In a case like this, I’d take the non-offset numbers. Good for Nucor to pay extra to (hopefully) improve the carbon numbers in the world. But for us, we’re selecting rebar with real world impacts that will happen regardless of the PPA.
For our clients, I’d caution against taking credit for materials that have sold their offsets. They’ve gotten some sort of financial benefit for selling off the carbon credits (lower cost of construction), and especially if this ties into GHG reporting, they should not be allowed to take credit for the sold carbon. As @lindseyengh mentioned - there are protocols for scope 3 reporting on this, and they should be followed.
My argument for the devils advocate side is only to say that in the wild west of voluntary reporting, I’m ok with these companies trying to prop up a revenue stream as long as they are transparent about it. I expect this to be a short lived loop hole as carbon literacy grows.