Jodie Lyn Brown’s ‘Cob Heart House’ sits at the top of a hill in Maleny, Queensland, surrounded by a garden full of fruit trees, herbs and vegetables. This beautiful hybrid home (half cob/half timber) is made even more special as it was built by Jodie herself with the help of a natural builder friend and a team of enthusiastic volunteers.
Jodie’s path to her cob house started when she separated from her husband and was living in the small town of Imbil. She’d purchased a large town block in an affordable area and had a house built for her. With four young children she had no plans to build her own home at that time.
Not long after she was drawn to the Crystal Waters Eco Village, where she ended up living for six years. It was at Crystal Waters that she was introduced to earthen homes and natural building. She found the perfect house to rent there, one made using rammed earth construction with the walls having a soft, earthy and nurturing feeling. Jodie was able to visit other earth homes, including rammed earth homes, a strawbale house and many which had been designed using passive solar design principles.
After attending a cob house workshop at the Bellbunya Community nearby, Jodie was inspired to embark on her own build. Cob is an ancient building technique which usually combines a sharp sandy aggregate (the structure), a clay heavy subsoil (the glue) and some straw (tensile strength). It’s used by many traditional cultures around the world and is slightly different depending on the location; sometimes it is mostly clay, sometimes ox blood is added, sometimes horse or cow manure. It is incredibly strong thermal mass material with the ability to bear the load from above, as well as catch and store the heat from the sun or the fire.
She sold her Imbil home and bought a lovely house with a huge northerly aspect verandah, wood heating and a wonderful permaculture garden on an acre plot of land at Crystal Waters. But as her children grew up and she was still commuting to her job in town, the daily drives became more challenging. Jodie was eager to take the next step to simplify her lifestyle, which meant moving closer to town. She was also feeling called to build something of her own with dirt and her own two hands!
Embarking On The Build
Jodie was living with three of her children, working three days a week and studying. With a sprinkle of synchronicity and determination, she found a rental home in Maleny to live in while purchasing her future cob house site. She had no previous hands-on building experience. She did however have some equity from her previous house, so she took on a mortgage to make this all possible and continued to live simply, growing her own food, being a homemaker and working part-time.
Jodie thrived during this busy period. ‘I always love working toward goals I have set for myself, which are very different from those imposed upon us,’ she says. ‘When we set our own boundaries, goals and steps to action we are motivated!’
She had a tight budget for her land purchase. At the time her property was one of the cheapest blocks in town at $170,000. It has a beautiful outlook up high with a flat space at the end of a small cul-de-sac backing on to pasture with cows, and 945 m2 (nearly ¼ acre) of lush growing soil. It’s only a two minute walk to the creek and a ten minute walk to town.
Brett from Ecolibrium Design came and looked at the plot, giving Jodie feedback and advice on the design project. He brought his own passion for natural building, great sustainable design ideas and a willingness to work within a budget. They worked together to create a beautiful four bedroom home.
It was designed as a hybrid home so that it would work with the site’s characteristics, such as its aspect and sloping landscape. Half of the home is grounded into the earth, with a concrete slab as the foundation, large cob walls and angled ‘wings’ of cob to catch the sun from the north, directing it into the windows to heat the thermal mass floors in winter. The other half is more conventionally built, with timber framing on hardwood stilts overlooking the valley.
The number one rule when designing with cob is to have ‘a good hat and boots’, meaning large eaves and decent footings/ stem wall to protect the home from too much water. As Maleny is a sub tropical high rainfall area, the eaves of Jodie’s home overhang by 900 mm and the footings rise up 300 mm above ground level, with the cob section not on the intense weather side of the house.
The home was easily council approved, probably due to the fact that the slab and cob walls are not load bearing but are rather infill between the timber wall framing. Jodie registered as an owner-builder by completing a three-day course, so as soon as the plans were certified she was ready to go.
She started the building process the way all good natural builders should: with tests, tests and more tests! She did some basic jar tests on various sections of earth from the property, which unfortunately weren’t suitable for cob. After ringing around for leads in her area, Jodie tested some subsoil down the road on a property owned by the local earthworks guy and found it was perfect. Paying only for his time and delivery, she got a huge truck of subsoil for about $200, which was enough earth for all of the cob walls in her home. The coarse sand needed for cobbing was the leftover sand from laying the slab and she also got a pile of bluestone offcuts called crusher dust.
Linda, a local cobbing legend, was hired by Jodie to run a weekend cob workshop on site. This meant people would come to learn about cob building and at the same time help build the walls of Jodie’s house. Jodie made flyers and distributed them far and wide, which meant the first working bee was well attended and full of fun, learning and laughter. This workshop was the kickstart she needed to continue building on her own, while working bees and generous helpers assisted her in raising the huge cob walls.
One Person’s Trash…
Everyone seems to love bottle bricks, those coloured specks of light shining in the earth walls, seen in so many earth homes (especially Earthships). They’re simply made from coloured glass bottles, a glass or tile cutter and some tape. Jodie’s house is full of them, sparkling in the sunlight. There is a collection of pale blue gin bottles, green sparkling apple juice bottles, a green retro ashtray taped to a clear preserving jar, and a green glass bowl.
All of the doors and windows in the cob side of the house are preloved, coming from the tip, demolition yards, eBay, Gumtree and local ads.
Jodie advises that when getting the final inspection by your certifier, as the owner-builder you must produce certain certificates for the materials in your home. When you use preloved doors and windows, you have no official documentation for the quality of the glass, so you can do one of the following: replace all glass and be sure to get your certificate by the supplier/installer, contract someone to add the glass film to bring it up to the standard required, or find someone who is authorised to measure the glass thickness and assess it.
Originally the land, with its long grass and rampant weeds, was somewhat of a blank canvas. Jodie has since transformed this small block into an edible landscape, with a food forest featuring native peanut trees, native black apples, Brazillian cherries, Davidson plums, Moringa, tamarillos, mulberry trees, guavas, limes, pawpaws, raspberries, hibiscus, avocados and more, with a thriving banana circle out the back.
Want To Build Your Own Cob House?
Jodie’s words of wisdom for anyone wanting to build their own cob house is to follow your heart, your passions and your loves. ‘We have this life to experience what we may, whatever it is,’ she says. ‘If you dream it, you only have to find the path how to do it, plan it as best you can with what you’ve got, and go for it. Jump in!’
Dani Wolff is a building designer, natural builder and educator who co-created Agari Farm and Agari Earth Builders. www.agarifarm.org
- The Hand-Sculpted House by Ianto Evans (Chelsea Green Publishing Company 2012)
- Building with Cob: A Step-by-Step Guide by Adam Weismann (Green Books 2006)
- The Natural Plaster Book by Cedar Rose Guelberth (New Society Publishers 2002)
- A Pattern Language: Towns, Buildings, Construction by Christopher Alexander, Sara Ishikawa and Murray Silverstein (Oxford University Press 1977)
- The Timeless Way of Building by Christopher Alexander (Oxford University Press 1979)
- Ecolibrium Designs www.ecolibrium.com.au