I’m researching comparative carbon caps enforced by building codes or promoted by certification programs. Europe seems to be leading in this area (France RE2020 requires new construction to comply with a holistic carbon budget (640-900 kgCO2e/m2) for all stages Cradle to Grave (embodied, operational, refrigerant) + transit. There are initial strides for embodied carbon limits in North America (Toronto: 350 kgCO2e/m2). ILFI Zero Carbon sets a limit of 500 kgCO2e/m2. While it’s great to see limits established and enforced, the challenge is that the non-harmonized inclusions and varying limit values add to the confusion around what is the target should be. Seeking references and other precedents that could be collected to create a fuller picture of what we should aim for in building design, what is truly ambitious and aligned with global climate policy. My dream is an enforceable code similar to RE2020 that is holistic and brings embodied + operational carbon into coherent relationship. I believe that a unified policy would go a long way to simplify, clarify and catalyze the actions required to rapidly decarbonize the industry.
Appreciate any precedents, links to similar research and articles about holistic carbon codes.
Note: RE2020 is enforceable but in early stages…a work in progress, not without snags. Réglementation environnementale RE2020 | Ministères Écologie Énergie Territoires
A few important notes for the Toronto policy…
- The building scope / object of assessment is limited to the structure and envelope.
- It’s based on “upfront” embodied carbon associated with stages A1-A5.
- Any parking structure that is part of the building should be included, both in the GWP (nominator) and the m2 (denominator). This varies from some other programs which only include parking in the nominator, but use the conditioned area (excluding parking) for the m2 value.
Each of the above lead to lower intensity values than might be seen in other policies which might have different details. So although Toronto’s policy is still very ambitious, it’s a reasonable number and not out of line with some of the other precedents you mention. There is also draft language which I believe will be official soon saying that the 350 value is for commercial office and residential buildings only, and that other building types will have a limit of 400.
All this to say, the details matter, and we shouldn’t just be quoting these intensity values without the context and rules that surround them.
PS - the Canada Green Building Council’s Zero Carbon Building Standard v3 (Performance Standard) also has intensity limits of 500 kg CO2e/m2 and a couple innovation levels that are lower than that. Again, the context and rules around these matter.
Appreciate the reply and yes, details matter. Each system has its own set of what’s being tracked, and each set has specific limits applied. The goal here is to understand how low we can go on the limits (what is “reasonable” based on location, and typology etc. ILFI’s 500 kgCO2e/m2 seems a bit lax today. Toronto already reflects a higher ambition. Can we push this further? Comparing across policies can help shed light on what is the proper target/level of ambition:
notes: IH = single family, CH = multifamily, O = office, E = Education; *B6-7 caps are part of different calculations “Ic energie” + “Ic eau”
I have a running list too. Can you send me the excel file, or the raw file for this and I will add them in? Good idea putting this together!
Excited to see a side-by-side comparison of these embodied and whole life carbon cap programs! Any chance you’d be willing to share once completed? I recommend adding LETI’s Embodied Carbon Target Alignment ratings to the list. Also, ICC and ASHRAE have a joint committee currently working on an enforceable North American standard along these lines, on which my colleague @lwalgenwitz may be able to share some insight into other precedents the committee has considered thus far.
@lkaufman thanks for starting the discussion. I believe Vancouver will be updating / publishing their policy later this year, @anthony.pak @patrick.enright? Should serve as good North American precedent–certainly lots of smart people writing and reviewing!
In support of ASHRAE standard efforts, SEI is also working on developing a prestandard for assessing structural LCA. Definitely looking to CLF for benchmarks V2 to inform these policies and appreciate the efforts to tidy up the LCA data ecosystem.
An interesting question to me is how much information do we actually need to make good decisions? We have SBTi limits that estimate CUI. Where ever we decide to draw the line, there are projects today that are being designed that are twice these limits. Whether it’s big basements or excessive spans or cantilevers that make us feel queezy, we already have a sense of what we should or should not be doing. It’s great to see some cultural shift around adaptive reuse, but how do we foster more of that and support a shift that makes the economics work?
Thanks Rowan for this reference, I’ll do a deep dive into their targets and try to integrate into the comparison. I do hope to share an update at some point!
Thank you Luke for the Vancouver reference. From my architect’s perspective, the caps are useful in conveying requirements to clients and builders, compared to the “% reduction from a baseline” approach. Studying the reduction from business as usual in the local jurisdiction is very interesting, but might not lead to meaningful enough reductions, which are needed.