Buy Clean Limits: Beat the Carbon Caps
State "Buy Clean" laws are moving from feel-good slogans to hard carbon caps. Miss the limit and your material never makes it onto the bid list. Here is what the latest thresholds look like, why EPDs are the only passport, and how to stay out in front even as Washington backpedals.


Why Buy Clean Keeps Jobs Local
Public buyers have discovered that every dollar aimed at low-carbon materials ricochets back into home-state manufacturing. When California capped the global-warming potential (GWP) of structural steel at 1,010 kg CO₂e per tonne (DGS, 2025), mills inside the state grabbed an instant advantage over imports that could not document lower footprints. Similar stories play out in Colorado cement kilns and New York ready-mix plants.
Carbon Caps by the Numbers
Colorado’s 2025 update puts 4,000 psi concrete at 301 kg CO₂e / m³ (OSA, 2025). California’s ceiling for hot-rolled beams now sits at 1,080 kg CO₂e / t fabricated. New York’s Buy Clean Concrete guideline, binding from 1 Jan 2025, pegs 3,000 psi mixes at 302 kg CO₂e / yd³ (OGS, 2024). These figures may look generous today, yet regional averages are falling by 4-6 % each year, so expect another haircut before 2027.
EPDs: The Only Acceptable Proof
Agencies will not accept lab reports, CSR brochures, or a polite email. They require a third-party verified Environmental Product Declaration that cites the correct PCR and shows modules A1-A3 clearly. No EPD, no waiver. Keep the document less than five years old and ensure the declared unit (tonne, cubic meter, etc.) matches the agency table. Forgetting this tiny detail has killed more bids than typos.
Map of State Rules Today
- California: Steel, rebar, flat glass, mineral-wool board. Concrete under study.
- Colorado: Asphalt, cement, concrete, glass, structural and reinforcing steel, wood.
- New York: Concrete only, but legislators signalled steel next. Fourteen other states have task forces exploring similar procurement caps. Federal rules? Gone. President Trump rescinded the 2021 Buy Clean executive order in January 2025, leaving the field to states (Sierra Club, 2025).
Spec Risk When You Miss the Cut
Failing a cap does not just lose one order. Designers often copy specs across projects; once you are flagged as “non-compliant,” that stigma follows. Rewinning trust can swallow an entire selling season. Meanwhile compliant rivals use their EPDs as marketing ammo and quietly steal your shelf space.
Choosing a Partner Who Accelerates
Embodied-carbon limits move fast. Your LCA team must move faster. Grill prospective consultants on three points:
- Average timeline from data pull to draft EPD.
- Experience aligning one product with multiple PCRs.
- Platform tools that collect plant data without sixty-column spreadsheets. If answers come in weeks instead of months, you have a shot. If they shrug at PCR versioning, run.
Take the Hint Before Bids Hit the Bin
Buy Clean caps are already carving up market share. Manufacturers who treat EPD prep as a late-stage paperwork chore will watch specs slip away. Those who bake low-carbon data into every product launch will grab the front row and probably recieve the premium pricing too.
Frequently Asked Questions
Do I need a separate EPD for each concrete mix sold to New York public projects?
Yes. The NYS guideline demands a mix-specific EPD showing GWP in kg CO₂e / yd³. Grouped or industry-average EPDs are rejected.
What happens if my steel EPD uses modules A1-A3 and A4 but California’s table is cradle-to-gate only?
Provide the EPD appendix where A1-A3 are listed separately; agencies will compare those numbers to the cap and ignore A4.
Can I rely on federal Buy Clean guidance instead of state rules?
No. The federal executive order was rescinded in Jan 2025. State caps now set the bar.
How often will Colorado review its GWP thresholds?
The Office of the State Architect must revisit limits every three years or sooner if market averages drop by 10 % (OSA policy note, 2025).