Thick hempcrete walls contribute to the peace and warmth inside this lovely central Victorian home.
It’s so refreshing to visit homes that are exactly enough for their occupants and no bigger – especially when they are built on expansive rural blocks where space is not an issue. Perched on a rise in the middle of a former potato field in Lyonville, central Victoria, Sarah Corbet and David Bruce’s new house appears even smaller from the road than it actually is, perhaps because of its neat, compact shape: it’s essentially a cube with a slice out of it to angle the roof.
The 75-square-metre footprint houses an airlock entry, bathroom, living, dining and full-sized kitchen with butler’s pantry. A mezzanine level over the kitchen and dining area is around 30 square metres and provides a spacious bedroom for the couple, with a long messmate trestle desk under the north-facing windows for working from home.
It’s not large, but the layout, high ceiling over the living space and generous windows all contribute to a sense of spaciousness. It’s also delightfully peaceful and cosy inside, even on the windy day when I visited. This is no accident, Sarah explains. “From the outset, we wanted to build something amazing to showcase good design: something adequately sized, affordable and appropriate for the climate.
“To be honest, we had no idea how cold it was here! We’re at 740 metres elevation: we get frosts from April to December and it snows several times a year. Initially we started out camping before graduating to a leaky caravan, then stayed in the shed that we built first, and finally moved into our finished home.”
The couple bought the three-hectare block in 2018 to build a home for their future retirement and for a change of pace: they plan to create a beautiful and productive permaculture farm.
“We were looking for good soil and water security,” says Sarah. “We love it here and already feel very much part of the local community. It’s a bonus that we have acreage in a town full of amazing gardeners and cooks, so we feel we are in the right place.”
Already interested in hempcrete as a building material, David and Sarah clicked with Joe D’Alo of the Hempcrete Building Company when they met him at Bendigo’s annual Lost Trades Fair (something of a misnomer in this case: while not well known here until fairly recently, hemp construction is very much burgeoning in Australia today; see our article elsewhere in Sanctuary 63 for the latest).
Sarah and David worked with building designer James Goodlet of Altereco Design on a simple design that they would be able to build themselves. “I was super excited because it was my first opportunity to design using hempcrete,” James says. “It was great to dive in and learn about it. We had to consider the process of assembling the hemp around the timber frame, with particular attention to the junctions – how the hemp interfaces with the window frames, the eaves and so on.”
Once the concrete slab was laid, David built the timber-framed structure. Joe supplied the hemp hurd, lime binder and mixing equipment, and gave the couple half a day’s instruction on how to set up the formwork and install the hempcrete.
“We had a lot of volunteers here to help with the hemp building,” says Sarah. “It was great. We met some lovely people, and they got hands-on experience for their own hemp builds – at least three of which are now underway.” She explains that it’s a pretty straightforward process. “Once the ply formwork is in place, you mix the hemp and lime binder with just the right amount of water in a pan mixer, and then tip it from tubs into the formwork, tamping the edges to make a firm wall full of insulating air. You have about 20 minutes to install it before the lime starts to go off.” The hemp walls took about two weeks to complete. When they were finished, David reused the ply as internal wall linings, painted with a clay milk paint mixed on site that matches the clay plaster on the hemp walls.
David and Sarah’s hempcrete walls are 300 millimetres thick, which is assumed to have an R value of 4.2 for energy rating purposes, but they believe it performs better than that. The hempcrete works with the insulated slab, R6 ceiling insulation and double-glazed windows to provide a thermally high-performing, draught-free building envelope. Hempcrete is resistant to fire, pests and mould; in addition, the breathability of the lime and clay plastered hemp walls keeps the air fresh and regulates humidity. “We were required to install an exhaust fan in the bathroom, but we find we don’t need to use it because the hempcrete breathes so well,” says David.
The couple encourage others to consider building with hemp. “If you’re doing it yourself, I’d recommend helping out on someone else’s project first so you can learn how it’s done,” says David. Sarah agrees, and also suggests finding an expert who can advise you and preferably supply the materials too. “It’s important to have access to good advice,” she says.
Finishing off the house has been a slow but satisfying process, as David has crafted most of the internal timber details himself. “I bought a truckload of salvaged messmate floorboards, and used them for everything from internal doors and architraves to the built-in shelving and kitchen drawer fronts,” he says. They’ve done most of the internal clay plaster themselves and are both now pretty handy with a trowel.
The result is a beautiful, restrained home, and Sarah and David can’t wait to be able to live in it full-time. “I love that it’s so comfortable, serene and calm,” says Sarah. “I like the muted material palette: nothing screams, it’s balanced and pared back. We feel so fortunate that we’ve been able to create this simple home ourselves, enjoy the process and share the journey with so many people.”
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