Materials Petal

Materials Petal

The intent of the Materials Petal is to help create a materials economy that is non-toxic, ecologically restorative, transparent, and socially equitable. Throughout their life cycle, building materials are responsible for many adverse environmental issues, including personal illness, habitat and species loss, pollution, and resource depletion. The Imperatives in this section aim to remove the worst known offending materials and practices and to drive business toward a truly responsible materials economy. When impacts can be reduced but not eliminated, there is an obligation not only to offset the damaging consequences associated with the construction process, but also to strive for corrections in the industry itself. At the present time, it is impossible to gauge the true environmental impact and toxicity of the built environment due to a lack of product-level information, although the Living Building Challenge continues to shine a light on the need for transformative industrial practices.


The Living Building Challenge envisions a future where all materials in the built environment are regenerative and have no negative impact on human and ecosystem health. The precautionary principle guides all materials decisions when impacts are unclear. There are significant limitations to achieving the ideal for the materials realm. Product specification and purchase has far-reaching impacts, and although consumers are starting to weigh these in parallel with other more conventional attributes such as aesthetics, function and cost, the biggest shortcoming is due to the market itself. While there are a huge number of “green” products for sale, there is also a shortage of good, publicly available data that backs up manufacturer claims and provides consumers with the ability to make conscious, informed choices. Transparency is vital; as a global community, the only way we can transform into a truly sustainable society is through open communication and honest information sharing, yet many manufacturers are wary of sharing trade secrets that afford them a competitive advantage, and make proprietary claims about specific product contents. Declare®, the Institute’s ingredients label for building products, is a publicly accessible label and online database with an official connection to the Materials Petal. Not only does Declare contribute to the overt methodology for removing a temporary exception, it also provides a forum for sharing the information compiled by a project team as part of their documentation requirements for certification.

There are temporary exceptions for numerous Red List items due to current limitations in the materials economy. Refer to the v3.1 Materials Petal Handbook for complete and up-to-date listings. The project cannot contain any of the following:

Red List materials or chemicals

• Alkylphenols

• Asbestos

• Bisphenol A (BPA)

• Cadmium

• Chlorinated Polyethylene and Chlorosulfonated Polyethylene

• Chlorobenzenes

• Chlorofluorocarbons (CFCs) and Hydrochlorofluorocarbons (HCFCs)

• Chloroprene (Neoprene)

• Chromium VI

• Chlorinated Polyvinyl Chloride (CPVC)

• Formaldehyde (added) • Halogenated Flame Retardants (HFRs)

• Lead (added)

• Mercury

• Polychlorinated Biphenyls (PCBs)

• Perfluorinated Compounds (PFCs)

• Phthalates

• Polyvinyl Chloride (PVC)

• Polyvinylidene Chloride (PVDC)

• Short Chain Chlorinated Paraffins

• Wood treatments containing Creosote, Arsenic or Pentachlorophenol

• Volatile Organic Compounds (VOCs) in wet-applied products

The project must account for the total embodied carbon (tCO2e) impact from its construction through a one-time carbon offset from an approved carbon offset provider.

The project must advocate for the creation and adoption of third-party certified standards for sustainable resource extraction and fair labor practices. Applicable raw materials include stone and rock, metal, minerals, and timber.

For timber, all wood must be certified to Forest Stewardship Council (FSC) 100% labeling standards, from salvaged sources, or from the intentional harvest of on-site timber for the purpose of clearing the area for construction or restoring/maintaining the continued ecological function of the on-site bionetwork. For stone, project teams must advocate to quarries and/or manufacturers of all dimension stone products used within the project for certification under the Natural Stone Council (NSC) 373 Standard. All projects must use, at a minimum, one Declare product for every 500 square meters of gross building area, and must send Declare program information to at least ten manufacturers not currently using Declare.

The project must incorporate place-based solutions and contribute to the expansion of a regional economy rooted in sustainable practices, products, and services. Manufacturer location for materials and services must adhere to the following restrictions:

• 20% or more of the materials construction budget must come from within 500 kilometers of construction site.

• An additional 30% of the materials construction budget must come from within 1000 kilometers of the construction site or closer.

• An additional 25% of the materials construction budget must come from within 5000 kilometers of the construction site.

• 25% of materials may be sourced from any location.

• Consultants must come from within 2500 kilometers of the project location.

This project must reduce environmental burdens from the extraction, processing, and disposal of materials and turn waste into a valuable resource through beneficial reuse.

The project team must strive to reduce or eliminate the production of waste during design, construction, operation, and end of life in order to conserve natural resources and to and ways to integrate waste back into either an industrial loop or a natural nutrient loop.

All projects must feature at least one salvaged material per 500 square meters of gross building area. Projects that are an adaptive reuse of an existing structure are exempt from this requirement.

The project team must create a Materials Conservation Management Plan that explains how the project optimizes materials in each of the following phases:

  • Design Phase, including the consideration of appropriate durability in product specification
  • Construction Phase, including product optimization and collection of wasted materials
  • Operation Phase, including a collection plan for consumables and durables
  • End of Life Phase, including a plan for adaptable reuse and deconstruction

For all project types, there must be dedicated infrastructure for the collection of recyclables and compostable food scraps.

A project that is located on a site with existing infrastructure must complete a pre-building audit that inventories available materials and assemblies for reuse or donation.