Mandatory requirements for cement procurement w/ low embodied energy

Andrée Iffrig

Sustainability Strategist

Associated Engineering

LEEDuser Basic Member

2 thumbs up

February 10, 2020

Our firm was asked by a government client in Canada to update their specifications for concrete to capture low embodied carbon as a performance metric. From the SDL group's knowledge of concrete procurement:

What are the chances of systematically obtaining cement specified with 10% lower carbon intensity? What's viable in the current market?
Are product specific EDPs for various mix designs widely available from concrete producers across the country (USA), or only in some geographic areas?
Is GWP the single most important measure of concrete's impact or is a holistic approach (all impact categories) preferred?

Thanks. Andree

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Kjell Anderson

Director of Sustainable Design

LMN Architects

LEEDuser Basic Member

4 thumbs up

Mon, 02/10/2020 - 22:00

Hi Andree, * 10% is very achievable in areas where fly ash or slag can be procured. I believe it can be procured nearly everywhere but have not attempted to do so in Canada. * There are many, many EPDs for concrete. Some providers provide them on demand for every mix design on a project, meaning you can verify at submittal review time whether it complies. You can look up on EC3 where EPDs already exist. https://buildingtransparency.org/dashboard/material-search. Search under concrete and then by region. * GWP is the most important metric for concrete. -Kjell

Nadav Malin

CEO

Green Commons, LLC

LEEDuser Expert

586 thumbs up

Mon, 02/10/2020 - 22:36

Hi Andrée, Others here have more direct experience with this than me, so hopefully they'll chime in, but my understanding is that the most impactful thing you can do is to move away from a prescriptive spec for concrete, and go with a performance spec instead. If you define the performance requirements and then put cost and GWP on an equal footing as procurement criteria you can, I hear, get 20-30% reduction at little or no cost increase. There are some slides about this from Jeremy Gregory of MIT in the deck called "BSA Embodied Carbon in Buildings presentation—Session 2: Materials and Carbon" on this page: https://www.architects.org/embodied-carbon-in-buildings-conference-program/conference-resources You might also want to post this query on the Green Guru's list, where you'll get input from the Contractors in our network. And be sure to catch the Tally webinar this Thursday, that was announced on that list.