Performance specs drive dematerialization strategy

Building Transparency, the Seattle-based organization behind the environmental product declaration-fueled Embodied Carbon Calculator (EC3), raises a “less is more” premise for carbon emissions-minded architectural, engineering and construction professionals. Authors of its latest report, Manufacturers Guide to Embodied Carbon, frame “dematerialization” as a strategy where the lowest cost, lowest carbon footprint specification results from a design requiring less raw material per unit of production. “Magnify the impact of this strategy by finding ways to reduce use of the highest-impact raw materials,” they note. “This requires identifying the raw material hot spots where per-unit embodied carbon is the highest. These often turn out to be your most expensive material inputs as well, so overall savings can be substantial on dematerialization projects.”

Building Transparency’s newest guide prepares manufacturers, producers and suppliers for the Buy Clean policies bubbling up at federal, state and local agency levels. It provides building carbon emissions accounting basics and steps for reducing construction materials, products or assemblies’ carbon footprints. It was developed by the group’s Materials Carbon Action Network (materialsCAN), representing members of the global building industry ready to act on embodied carbon in project specifications.

materialsCAN members and Manufacturers Guide authors should see eye to eye with Georgia-based MEGASLAB, the subject of this month’s cover story. Since our July 2019 visit to one of its first commercial installations, MEGASLAB has built a track record of engineering and finishing heavy industrial and vehicular pavements with thinner cross sections than normally placed for such conditions. In a recent project for an owner keen on construction costs, schedules and embodied carbon metrics, MEGASLAB authorized installer Wayne Brothers demonstrated the potential to reduce an industrial floor thickness by 50 percent using high performance concrete mixes and premium finishing techniques. Beyond lowering concrete volume requirements of a conventional 9-in. thick slab, the proposed 6-in. thick alternate design brought additional carbon savings by eliminating nearly all steel reinforcement that would otherwise be used to control drying shrinkage cracking.

MEGASLAB’S demonstrable dematerialization mirrors last month’s report (pages 64-65) on UHPC Solutions North America’s production, placement and finishing of 5,000 yards of Ductal brand mixes forming a 2- to 3-in. overlay across four miles of Delaware Memorial Bridge deck area. An early-2000s product of the Lafarge Group research & development center in Lyon, France, Ductal was the first ultra-high performance concrete on the world stage, delivering the structural efficiency of a material with 18,000-plus psi compressive strength. Over a nearly two-decade window, Holcim US and Lafarge Canada businesses have worked with dedicated Ductal teams to apply the UHPC technology to cast-in-place or precast structures and elements. Other entities have developed their own UHPC formulations for bridge decks or joint closures; architectural elements, including thin panels (< 1 inch) for rain screen or other premium enclosure systems; and, site or home furnishings.

Concrete producers have helped anchor Building Transparency’s core offering, the EC3, by validating the deepest EPD library in the construction supply chain. Through promotion and delivery of high performance or UHPC solutions like MEGASLAB and Ductal, ready mixed and manufactured concrete producers provide very tangible examples of dematerialization, another tool advancing the Building Transparency mission.

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