Hempcrete: The Carbon-Negative Building Material the Construction Industry Ignores

What Is Hempcrete?

Hempcrete is a biocomposite made from the inner woody core (hurd) of the hemp plant mixed with a lime-based binder. It is:

• Carbon negative (absorbs more CO₂ than it emits)
• Naturally fireproof (no chemical treatments needed)
• Pest and mold resistant
• An excellent thermal and acoustic insulator
• Gets stronger over decades as the lime continues to petrify

The Numbers

• 1 cubic meter of hempcrete sequesters approximately 110kg of CO₂
• Hempcrete walls have an R-value of 2.5 per inch
• A typical hempcrete home sequesters 20+ tonnes of CO₂
• The material lasts 600+ years

Why It's Not Mainstream

The concrete industry generates 8% of global CO₂ emissions. It is a $600 billion industry. Hempcrete threatens this monopoly.

Building codes in most countries were written in collaboration with the concrete and steel industries. Hempcrete doesn't fit their testing frameworks — not because it fails, but because the frameworks weren't designed for carbon-negative materials.