The bill aims to reduce embodied carbon emissions in buildings and building materials by establishing new regulations within the Washington state building code. It mandates the state building code council to adopt rules for embodied carbon emissions reductions applicable to new constructions, additions, and renovations of buildings over 100,000 square feet, excluding school district projects. The bill outlines three compliance pathways for projects: maintaining a significant portion of an existing structure, demonstrating reduced life-cycle stage emissions of covered products, or conducting a whole building life-cycle assessment. Additionally, the council is tasked with defining covered products and establishing reporting requirements for compliance.

The legislation also introduces a public database for tracking embodied carbon emissions reductions, which must be maintained by the department of commerce. It requires the design professional of record to submit data on a standard form, detailing project specifics and compliance pathways. The bill sets a target for a 30% reduction in embodied carbon emissions by 2030, with incremental goals leading up to that date. The state building code council is responsible for reporting progress and ensuring that future building codes align with these emissions reduction targets.