Modern Hemp Building - A revolutionary natural design & building system for Australia. • Healthy Spaces by Design

Creating a healthy, naturally beautiful and harmonious home has finally become more accessible for Australians in recent years. The most promising and affordable natural building system that I have investigated and used is Hempcrete, which has been used more widely overseas. It provides a wonderful platform to create a healthy, sustainable and natural home to suit a modern lifestyle.

By creating a house that is constructed or renovated with Hempcrete, you will not experience the common issues of allergies, toxicity, mould growth and environmental damage associated with the more standard and synthetic building practices. Instead, you are building with renewable, natural and low-carbon materials, which are healthy and use low processing and energy to create the building. This sustainable building method also provides a healthy and low-toxic indoor environment. These spaces are naturally calmer and are more harmonious to live in. This leads to enhanced health and wellbeing for all occupants and creates a strong base to live a healthy and joyful lifestyle.

Some of the wonderful properties of building with hemp are:

Excellent thermal performance
Maintains stable internal environment (air, temperature, humidity)
Easy, light and fast to work with
Vermin proof (including termites)
Fire proof
Low embodied energy
Excellent carbon-positive footprint
Rot resistant
Regulates humidity (prevents mould)
Healthy, low-toxic breathable walls
Recyclable + compostable material
High acoustic performance
Air tight system (no thermal bridging)
Walls can featured or rendered with lime & clay (maintaining breathability)
Energy savings due to high performance of building system
Affordable (cost equivalent to brick veneer system)
Renewable & regenerative crop
Certified system in Australia (when using certified product and process)
‘Paddock to Place’ concept: ‘grow’ your own house in 4 months on 1 hectare of land (typical 3 bedroom house)

All you need to build a hemp wall

Removing the formwork for a hemp wall

Mixing the Ingredients for a hemp wall

‘Hempcrete’, also known as ‘Hemp Masonry’ or ‘Hemp Lime’ construction, is a highly sustainable, low-embodied energy product that is has excellent thermal insulation properties. It is a simple, non-load bearing infill wall system that is made from just a few ingredients: hemp hurd, lime, sand and water. These are mixed in a large mixer on site, placed into buckets and then tapped into place to create walls in-between two boards (shutters/ formwork). As well, it can be used for subfloor and ceiling insulation, creating a more homogenous building envelope. Any left over hemp and general clean up is simply composted back into the garden! The boards are removed after about a day and left to cure for a few weeks.

You can either feature the hemp walls naturally or render over them with natural clay or lime renders in any colour to suit. The natural hemp walls look similar to a rammed earth wall yet a lot easier and cheaper to construct. Or hemp walls can use natural renders to many affects, from undulated rustic to a more traditional (cement) rendered house as desired. A high standard of quality control is still required for building with hemp. Using products and processes that have been certified is also important for ensure quality of the final hemp building.

This is true sustainable and healthy living as it reduces its impact on the environment from building, creating inherently energy efficient spaces, which are good for your health and wellbeing.

Fresh Hemp Wall

Hemp Crop (Image courtesy of Industrial Hemp Alliance)

Building a home using hempcrete is carbon positive, which means that you are actually improving the environment by building a hemp home as it is removing carbon from the atmosphere. This is a critical factor that the construction industry needs to address, as it is commonly known to be one of the largest contributors to this global environmental issue. This natural building method now provides an opportunity for more people to create a difference and lead healthier and more sustainable lifestyles.

When you build a natural home from hempcrete along with its lower energy demand-in-use, it has been reported that you will be sequestering (or removing and storing) around 4.3 tonnes of carbon dioxide (CO2) as compared to adding 10.7 tonnes of C02 to the environment for a typical brick-block house of the same dimensions.

The hemp crop grown for building can be done on 1 hectare (2.4 acres) of land and takes about 4 months to grow enough for a standard 3 bedroom home. The hemp hurd is the woody inner part of the plant and is actually considered a waste/ by-product as the crop it not grown for this traditionally. The crop itself has many benefits and enhances biodiversity. As it’s fast growing, it requires minimal pesticides or fertilises as the dense canopy naturally supress’s weeds making it a low-toxic material. It also regenerates the soil with the root structure of the crop, making it a great crop between cereal or potato crops and remediating land and provides many benefits to farmers.

The hemp crop used to build a house is also different to other varieties of the Cannabis Sativa plant, which are more commonly known as Marijuana and contains no or very low levels of THC the cannabinoid associated with the psychoactive properties of marijuana. There are varying laws in different states of Australia that regulate industrial hemp use. Generally, it can be grown and accessed for building since 1998 in Australia and the market is growing as the benefits of industrial hemp become more widely known here. There are also many benefits to supporting the Australian famers and Australian Industrial Hemp Industry by sourcing your hemp for building here than going overseas and keeping it a low-embodied energy process. You can also visit the Australian Industrial Hemp Alliance for more information on the versatility of products that hemp crops provide, from: food, fibre, clothing, rope, building, medicine, biofuels and biocomposite materials to replace plastics. I have also more info on Hemp foods here.

Hemp Wall of a House

Placing hemp mix in to then tap into place

Tapping the hemp in to make wall

A healthy and harmonious home and work environment is emerging to be an important factor in our overall health and wellbeing. There is plenty of research that indicates our modern home and work environments are unhealthy and actually a leading cause in many health issues being experienced today. Our indoor environments are now proven to be 10x times more polluted than outside and we are spending much more of our time indoors. Most of us are aware of the role that diet and exercise play in healthy living. However, many are unaware that most of this can be undermined when we live in an unhealthy home and/or workplace.

Many factors influence the health of a building including: allergens, particulates, chemicals and toxins present in the home; water, light and air quality; exposure to electro-magnetic, radiofrequency fields and geopathic stressors. As well, we are building homes and workplaces using highly processed, synthetic building materials with ‘tight’ energy efficient designs that don’t allow a building to naturally breath. Surrounding conditions to the house, reduced outdoor connections/ access; home gardening/ food growing & lack of basic permaculture principles also affect us in many ways. Again, having an awareness of these factors is an important step towards healthy living for you and your family.

By choosing Hempcrete from your natural design and building ‘toolkit’ you are well on your way to creating a naturally beautiful, healthy, sustainable and harmonious home.

Further resources and information about hemp building can be found below for your interest: