Updating structural specifications to reduce embodied carbon can help a firm commit to lowering their carbon footprint on all projects. The way specifications are written can also drive market change, affecting the way manufacturers develop new materials.
While re-writing specifications can seem daunting, there are a variety of ways specifications can be revised to potentially reduce embodied carbon ranging from simple changes to complete overhauls. Different strategies may work better for different firms and different types of projects. Compiled below is a list of tips and strategies that have been successfully used by structural engineering firms and material experts to reduce embodied carbon with specifications.
Note – SE 2050 does not endorse any specific strategy. Firms may choose to use one of these strategies, a variation of one strategy, or a combination of multiple strategies. Best practices are for your firm to decide.
Tips from the experts…
- Embodied carbon reduction requirements can be incorporated within standard material specifications, or as an addendum to be included on a select project basis.
- Early communication with both the client and the entire project delivery team is critical to meeting embodied carbon reduction goals. Consider including a preconstruction meeting on project embodied carbon goals as a specification requirement.
- Host an embodied carbon charrette and/or provide a cover letter to the General Contractor and/or preconstruction manager that includes an introduction to embodied carbon and the embodied carbon goals for the project. This is especially important in regions where manufacturers and suppliers are unfamiliar with embodied carbon. (Note: the cover letter would be for information only and not considered a contract document.)
- Re-evaluate concrete specifications to eliminate unnecessary prescriptive requirements on materials such as minimum or maximum cement content, minimum or maximum fly ash or slag content, maximum w/cm ratio, etc. Consider specifying only performance requirements, such as compressive strength and exposure class.
- Specifications ultimately need to allow for competitive bidding. This is important to keep in mind as specification updates are made.