How to Make Hempcrete

If there’s one type of sustainable building material that’s changing the game, there’s no doubt that it’s Hempcrete.

With its remarkable blend of breathability, strength, and eco-friendliness, this bio-composite material made from hemp hurds, lime binder, and water is quickly rising to the top as an ultimate favourite for natural builders, architects, and eco-conscious homeowners alike.

Unlike conventional concrete, hempcrete is carbon-negative, highly insulative, and promotes healthier indoor air. You can easily purchase it from leading hempcrete suppliers in Australia, or you can even make it yourself. Whether you’re experimenting with small-scale projects or dreaming of building a high-performance home, understanding how to make hempcrete is your first step into the world of green construction.

How Much Hemp Does It Take to Make Hempcrete?

To make hempcrete, you’ll need three main ingredients:

• Hemp hurds (also called hemp shiv) – the woody core of the hemp stalk

• Lime-based binder – typically hydrated lime, sometimes mixed with pozzolans or hydraulic lime

• Water

As a general rule of thumb, the ratio is roughly:

• 1 part binder
  
  

• 1.5 parts hemp hurds
  
  

• 1 part water (adjust based on workability)

To create 1 cubic metre of hempcrete, you’ll need:

• Around 110–120 kg of hemp hurds
  
  

• Approximately 220–250 kg of lime binder
  
  

• About 60–80 litres of water

These numbers may vary depending on the exact mix and intended application, but they offer a solid starting point for most builds.

How to Make Hempcrete Panels

Hempcrete panels are precast wall sections designed for easy installation and consistent quality. They’re lightweight yet strong, breathable, and excellent at regulating temperature and moisture.

How They’re Made

Hempcrete panels are typically produced in a controlled factory setting using formwork or moulds. Here’s a simplified process:

1. Prepare the mix – Combine hemp hurds, lime binder, and water until you get a fluffy, workable consistency.

2. Pour into moulds – The mix is placed into flat, framed moulds lined with mesh or timber, often with an internal frame for extra strength.

3. Compress and cure – Light tamping is used to remove air pockets. The panels are then left to cure and dry naturally, which can take several weeks depending on humidity and thickness.

Best Uses

• Prefabricated homes

• Internal partition walls

• Fast-track construction projects

• Builds with limited on-site mixing capacity

Installation Highlights

• Panels are usually screwed or bolted into timber or steel framing

• They may be finished with natural renders or cladding

• Require minimal on-site mess and reduce build time

How to Make Hempcrete Blocks

Hempcrete blocks are large, precast masonry-style units made using the same basic hempcrete mix but shaped and cured into block form.

How They’re Made

1. Mix the hempcrete – Same proportions as above: lime binder, hemp hurds, and water

2. Pour into block moulds – Moulds are shaped to create standard or interlocking blocks

3. Lightly compact and cure – The blocks are tamped and left to dry over several weeks

These blocks are non-load bearing, so they’re often used in conjunction with a structural timber or steel frame.

Best Uses

• External and internal wall insulation

• Passive house projects

• DIY builds where consistency is key

Installation Highlights

• Installed like traditional masonry using mortar

• Can be dry-stacked if interlocking

• Easy to cut and shape on-site

Thinking about buying ready-to-use products instead? Check out our hempcrete blocks cost calculator. 

How to Make Hempcrete Bricks

Hempcrete bricks are smaller than blocks, closer in size to conventional clay bricks, and offer more flexibility for detailed or curved structures.

How They’re Made

1. Create the mix – Blend your hemp hurds, lime binder, and water

2. Pour into smaller brick moulds – Often done manually or with small-scale casting tools

3. Cure slowly – Allow the bricks to dry in a well-ventilated, shaded area for several weeks

Because of their size, they’re perfect for those smaller projects or intricate builds that require more shape adaptability.

Best Uses

• Feature walls or artistic designs

• Interior partitioning

• Restoration projects requiring fine detail

Installation Highlights

• Laid with natural mortar like clay bricks

• Great for curved or custom-shaped walls

• Slower to install than blocks but the ideal choice for better precision

Meet The Finest Hempcrete on The Block: Respirabuilt 

Hempcrete is way more than just another building material; it’s an empowering lifestyle choice that embraces health, sustainability, and comfort. Whether you’re casting your own panels or laying hempcrete blocks, every step brings you closer to creating a space that breathes with you and lasts for generations.

Let’s be real: Not all hemp-based building materials are created equal. At Respirabuilt, we hold ourselves to the highest standards that are second to none. Our expertly crafted blocks and panels deliver performance, purity, and peace of mind. You deserve nothing less.

Here’s why we’re the go-to choice for hempcrete blocks in Australia:

Contact us today to start bringing your eco-build vision to life with confidence.

Looking for more expert insights? Take a look at our other helpful blogs below:

• Hempcrete disadvantages

• How Does Hempcrete Compare to Traditional Insulation Materials?

• What Are the Benefits of Hempcrete?