Hempcrete Companies in the US: Suppliers, Block Makers and Builders

What hempcrete is

Hempcrete is a mix of hemp hurd, a lime-based binder and water. Hurd is the woody core of the hemp stalk, left over when the fiber is removed (see hemp fiber).

It is not structural. The US model code treats hemp-lime as nonbearing infill: a frame carries the loads and the hempcrete fills and insulates the wall.

The code reference is the 2024 International Residential Code, Appendix BL, Hemp-Lime (Hempcrete) Construction, published by the International Code Council (ICC).

What Appendix BL means for a project

Appendix BL gives builders a written standard for hemp-lime walls, but only where it has been adopted. IRC appendices are optional. A state or local jurisdiction has to adopt Appendix BL before it is enforceable, as HempBuild Magazine explains.

Key points, as summarized by the US Hemp Building Association in August 2026:

• Hemp-lime is nonbearing infill. The framing carries the load.
• Dry density must be 12.5 to 25 pounds per cubic foot (200 to 400 kg/m³).
• The appendix sets thermal values from R-2.10 per inch at low density to R-1.20 per inch at high density.
• In force: Austin, Texas (effective July 2025), Maricopa County, Arizona, and the City of Surprise, Arizona.
• In progress, not adopted: Minnesota and Virginia. Washington has a state code section taking effect in May 2027 that lets local jurisdictions adopt it. A 2024 proposal to the Washington State Building Code Council asked for statewide adoption.

HempBuild Magazine reports that Appendix BL allows hemp-lime in homes up to two stories in low seismic risk regions without engineering. Higher seismic risk or taller buildings need an engineered design. Where the appendix is not adopted, it can still be proposed to the local building official for a single project.

Adoption status moves. Ask your building department which code edition and appendices apply before you design. This is general information, not code advice.

US hempcrete companies

The 20 companies below were checked on October 9, 2026. Each has a live website, and each description uses only what the company states on its own site. The list is alphabetical by state. It is not a ranking, and inclusion is not an endorsement.

Stock and services change. Hemp Traders, for example, showed its sample hempcrete kit as sold out on the day of the check. Confirm availability, lead times and licensing with each company.

How to use this list

Start with the role you need, because few companies do everything.

• Hurd: processors and resellers supply the hemp. Ask for the particle size and dust level, and whether the hurd is sold for building use.
• Binder: lime binders are formulated products. Use the mix ratio from the binder maker’s data sheet.
• Blocks and panels: pre-cast blocks and prefabricated panels are made off site, then laid or assembled on the frame.
• Installers and builders: ask for finished, permitted projects in your state.
• Training: several companies above run workshops for owner-builders and trades.

Recent projects show how these roles combine. HempBuild Magazine reported in October 2026 on a Colorado house built by Healthy Hemp Homes, with hempcrete installed by Hemp Building Company and hurd from South Bend Industrial Hemp.

On fire performance, HempBuild Magazine reported in July 2024 that a 12-inch spray-applied wall by Americhanvre earned a 1-hour rating under ASTM E119 at Intertek in York, Pennsylvania. Ratings belong to the tested assembly, not to hempcrete in general.

US Hemp Building Association

The US Hemp Building Association (USHBA) is a membership trade association for hemp building. Its stated mission is “to support and advocate for hemp building professionals, projects, and materials in the United States.”

HempBuild Magazine reported in June 2026 that the association was founded in 2019 and was moving to a new website. That site, ushempbuilding.org, was live on October 9, 2026. The older ushba.org address did not load that day.

The association’s site lists a research database, an architects toolkit and an “AIA/CEC Hemp 101” course.

Next step

For the crop behind the material, see industrial hemp. For measured properties of hempcrete and a UK supplier list, see hempcrete in the UK.