Hempcrete FAQ

Here are some common FAQ about hempcrete that we get asked all the time.

If you’re question is not listed here please send us a message and we would be happy to help you.

Alternatively, there are some great resources to be found here.

Hempcrete or hemp lime is biocomposite material; a mixture of hemp hurds (shivs) and lime and water.

When hempcrete is used as an insulating wall system, it is not stronger than concrete.

Hempcrete is not load bearing when used as an insulation material.

Hempcrete can be used instead of concrete wherever concrete is not load bearing.

Hempcrete materials cost around $600AUD per cubic metre.

For a 250mm thick wall, this is around $150 plus freight.

Hempcrete is excellent value. There are other building materials that are cheaper, however they do not provide the hygrothermal properties of hempcrete. Hempcrete significantly reduces HVAC and maintenance costs compared to other materials.

The natural lime provides hempcrete with excellent properties to resist mold, fungus, bacteria and virus propagation.

For hempcrete insulation, it is not recommended to use sand. Sand is used for hygrothermal renders only.

Free-form hand applied to existing substrate (wall) in layers 20-50mm thick. Hand-cast between temporary form-work for internal feature walls. Mechanical projection onto substrate (sisal).

Hempcrete is the most carbon neutral, sustainable, healthy building material for liveable spaces. Its versatility means that hempcrete can replace many building materials and trades, thereby affording a more sustainable and valuable build.

OzHemp Tradical hempcrete is the ONLY CERTIFIED hempcrete material in Australia.

There are other hempcrete materials that proposedly are DEEMED TO SATISFY the Australian Building Code, however, these have not been independently certified.

As of 2021 nearly 1,000 hempcrete homes have been constructed in Australia.

No additives or chemicals are introduced to the mix…it is all natural.

Due to the natural properties of hempcrete; durable, moisture resistant, heat resistant, fire resistant, mold resistant, termite resistant, hempcrete is very suitable to the harsh climates of Australia.

Rain will slowly erode hempcrete (over many, many years) so it is recommended to provided a water repellent coating, render or cladding to weather exposed faces.

Hempcrete can be made waterproof through the addition of natural waterproof renders and other coatings.

Hempcrete cures by releasing moisture into the atmosphere that was added during mixing.

Depending on the environmental conditions, the original water content, the wall thickness, the density and types of lime and hemp used, drying times will vary significantly.

The R-Value of Hempcrete depends on the type of hempcrete mixture used (wall, floor, roof, render) and the thickness of the application.

Hempcrete provides excellent thermal mass and insulation properties, it also regulates moisture levels by absorbing and releasing moisture as required to maintain optimum healthy air.

Hempcrete has superior thermal, acoustic and electromagnetic insulation properties.