Buy Clean Colorado Act

The Buy Clean Colorado (BCCO) Act (C.R.S. 24-92-117) applies to State public projects for which the cost exceeds five hundred thousand dollars and for which an agency of government issues a solicitation on or after January 1, 2024. Public projects include any construction, alteration, repair, demolition, or improvement of any land, building, structure, facility, road, or bridge that is intended to promote public upkeep. The Office of the State Architect (OSA) will administer a program pertaining to all construction projects for state agencies and institutions of higher education whereas the Colorado Department of Transportation (CDOT) will administer a program relevant to CDOT's horizontal construction projects only. 


This law requires the OSA to establish a maximum acceptable global warming potential (GWP) limit for each category of eligible materials (identified below). These materials are the focus for Buy Clean Colorado due to their high carbon emissions impact and volume use in public projects and since reducing the impact of these materials will provide the greatest reduction of greenhouse gas emissions during the construction of State public projects. Through design optimization and responsible selection of materials, reduction of embodied carbon emissions from building materials can be accomplished.


Buy Clean Colorado Act Policy (Rev. 07/2022)


Eligible Material Categories:

  1. Asphalt and Asphalt Mixtures
  2. Cement and Concrete Mixtures
  3. Glass
  4. Post-tension Steel
  5. Reinforcing Steel
  6. Structural Steel
  7. Wood Structural Elements

For GWP Thresholds, please review the attachment. 

OSA Max. GWP Thresholds_2023-06

Educational Materials

The following list will be updated as educational and training events occur.

August 29, 2022 - Buy Clean Colorado Act: Association Meeting

December 13, 2022 - Buy Clean Colorado Act: Early Agency/IHE Presentation

March 20, 2023 - Buy Clean Colorado Act: Agency/IHE Training #1

"Agency of government" or "agency" has the same meaning as defined in section 24-92-102 (1), C.R.S., meaning any agency, department, division, board, bureau, commission, institutions, or section of this state which is a budgetary unity exercising construction contracting authority or discretion. 

"Cost" has the same meaning as defined in section 24-92-102 (3), C.R.S., meaning the total cost of labor, materials, provisions, supplies, equipment rentals, equipment purchases, insurance, supervision, engineering, clerical, and accounting services, the value of the use of equipment, including its replacement value, owned by a state agency, and reasonable estimates of other administrative costs not otherwise directly attributable to the public project which may be reasonably apportioned to such project in accordance with generally accepted cost accounting principles and standards. 

Eligible materials” means materials used in the construction of a public project, including:

  • Asphalt and asphalt mixtures
  • Cement and concrete mixtures
  • Glass
  • Post-tension steel
  • Reinforcing steel
  • Structural steel
  • Wood structural elements

Eligible project” means a public project as defined in section 24-92-102, C.R.S., for which an agency of government issues a solicitation on or after January 1, 2024; except that “eligible project” does not include any maintenance program for the upkeep of a public project or any road, highway, or bridge project.

“Embodied Carbon” is reported as global warming potential (GWP) and includes greenhouse gas emissions arising from the production, construction, use, and end-of-life of products or systems used in the construction of buildings, roads, and other infrastructure. The BCCO Act is focused on reducing the embodied carbon emissions generated during the production stage (Stages A1-A3).

Environmental Product Declaration” or “EPD” or “Type III EPD” means a third-party verified document that summarizes stages A1-A3 of a life cycle assessment (LCA) for a single product and publicly discloses its environmental impacts. For an EPD to be deemed approved:
(A)   The EPD must be a current product-specific, Type III EPD.
(B)   The EPD must reference all ISO Standards - ISO 14025:2006, ISO 14040:2006, ISO 14044:2006, and ISO 21930:2017 or EN 15804.
(C)   The EPD must align with the applicable product category rule requirements.
Agencies, consultants, and contractors shall demonstrate compliance with these requirements by verifying that the GWP value in the submitted EPD is less than or equal to the maximum acceptable GWP limit established by OSA for each eligible material.

Global warming potential” or “GWP” is the potential climate change impact of a product or process as measured by an LCA, reported in an EPD.

Life Cycle Assessment” or “LCA” is an independently verified study of a product or building. Product-level LCAs must be done in accordance with ISO 14040 and ISO 14044 for incorporation in a product’s environmental product declaration.

Operational Carbon” is the amount of carbon emitted during the operational or in-use phase of a building. This includes the use, management, and maintenance of a product or structure. The BCCO Act does not pertain to operational carbon emissions. The following image demonstrates embodied carbon (yellow) and operational carbon (blue) across the key life cycle stages.

Embodied carbon (yellow) is the main emissions contributor during the raw material extraction, manufacturing, construction/installation, maintenance, deconstruction, and disposal phases. Operational carbon (blue) contributes to emissions during the operational phase of the building.


Product category rule” or “PCR” means a set of specific rules, requirements, and guidelines necessary for developing Type III environmental declarations for one or more product categories.

Project description” has the same meaning as defined in section 24-92-102 (7), C.R.S., meaning the words used in a solicitation to describe the construction to be performed, and includes specifications attached to, or made a part of, the solicitation. 

Public Project” has the same meaning as defined in section 24-92-102 (8), C.R.S.
(A)  “Public project” means any construction, alteration, repair, demolition, or improvement of any land, building, structure, facility, road, bridge, or other public improvement suitable for and intended for use in promotion of the public health, welfare, or safety and any maintenance programs for the upkeep of such projects. [Exemption from “eligible project” definition]
(B)   Except as provided in paragraph (C) of this subsection (8), “public project” does not include any project for which appropriation or expenditure of money may be reasonably expected not to exceed five hundred thousand dollars in the aggregate for any fiscal year. Nothing in this paragraph (b) shall affect the requirements for the delivery of bonds or security pursuant to sections 24-105-202, 38-26-105, and 38-26-106, C.R.S.
(C)   “Public project” does not include any project under the supervision of the department of transportation for which appropriation or expenditure of funds may be reasonably expected not to exceed one hundred fifty thousand dollars in the aggregate of the fiscal year.

Stages A1 - A3” refers to the life cycle stages which define an EPD from cradle-to-gate and include the raw materials extraction and processing, transport to the manufacturer, and manufacturing of building materials. BCCO Act Compliant EPDs shall summarize Stages A1-A3 of an LCA and may include A4 - Transport to Site. The following image demonstrates the life cycle stages that are typically included in EPDs. 

Life cycle stages included in EPDs. Stages A1-A3 are required for all EPDs. Stages A4-A5, B1, C2-C4, and D are included in some EPDs. Stages B2-B4 and C1 are rarely included in EPDs.


Type III EPD” or “Type III Environmental Product Declaration” means a third-party verified product-specific life cycle assessment report which covers a single product from a manufacturer. Type III EPDs conform to international standards and facilitate comparison of the environmental attributes of products that meet equivalent functional requirements.