Case study: a tiny home with a big vision
Willow Aliento | 22 February 2018
A small home project in Geelong by Manage Carbon principal Vicky Grosser is showcasing a way to address some of the big issues in the residential sector, including affordability, density, build quality and sustainability.
Grosser made the decision to downsize, but because under Victorian planning laws secondary dwellings are currently only permitted for dependent relatives, putting a small house on her existing home’s block first required subdividing the block.
Grosser told The Fifth Estate the process of subdivision cost around $40,000, including planning, surveying and permit costs, as well as infrastructure installation including power, NBN, water supply and sewerage.
The 30-square-metre split-level home was designed for her by Dan Prochazka. As the project moved into the initial stages, the building team also collaborated on refinements to the design, Grosser says.
The hand-picked team included Geelong builder Mark Lane Quality Builder, carpenter Duff Swanson of Restoration Carpentry, permaculture leader and carpenter Pete Baird, Leanne Nichols and Robbie Nichols from Green Earth Electrical and Brad McPhee of Southend Plumbing.
Grosser herself also undertook hands-on work, including cleaning the reclaimed bricks used for the groundfloor living area, painting doors and windows, and fitting insulation.
Using as many reclaimed and low-carbon materials as possible was a priority. There were finds including stained-glass windows, which Grosser triple-glazed to improve thermal performance.
Marmoleum was used instead of PVC-based vinyl for wet area and kitchen flooring, and sustainable timbers including recycled timber used for loft flooring, stairs, balustrades and decking.
The home has achieved a NatHERS rating of 7.2 stars, but Grosser says 12 months of monitoring will be undertaken to measure actual performance, which is expected to exceed the rating.
The monitoring will also establish whether there is a case for her to invest in a 2kW solar battery storage system to connect to the 1kW solar PV system mounted on the adjacent shed, which will supply power to the home. The home is also connected to mains grid power.
Water is being harvested and stored for re-use in toilet flushing. Grosser says calculations were undertaken to ensure that all water falling on the roof of the house would be captured if possible.
As the project unfolded, Grosser says even the building inspector became engaged in design and delivery.
The inspector initially asked why the project had such high-end structural engineering specifications, she says. Having a background as a joiner, his interest was piqued, and he also became involved in the final design.
“He said the house will withstand a tornado.”
She says throughout the whole process of the build, which is now at lock-up after 45 days of construction, she learnt to “succinctly explain the purpose of the project”.
“Everyone was enchanted and contributions were made, including donations such as specially-made kitchen and bathroom tiles by a friend, wooden bench tops, and freshly grafted small fruit trees.”
Waste for the build has been kept to such a minimum that it is unlikely it will require even a full skip bin, Grosser says. Scrap steel and surplus floor insulation were both on-sold. Plastic sheeting from materials was then repurposed as covers for other things on site.
“It doesn’t take time [to reduce waste], you just have to work well together.”
The property being located on Aboriginal land was also an important focus for Grosser.
In 2010, when she first purchased the property, local Wadawurrung elder Uncle David Tournier did a smoking ceremony.
The first morning of the build, Grosser did a small ceremony with the carpenters, conducting an Acknowledgment of Country, and promising to care for it during the build.
The subdivision has also created an opportunity to name the back lane, which will be the front address for the new dwelling.
Grosser consulted Traditional Owners and discussion led to it being named Parrwang Lane, which means “magpie”.
Grosser says capital that will be freed up by her shift into the small house and renting out her existing home will be channelled into initiatives for local Indigenous people.
“I will be paying the rent for my family living for four generations on Aboriginal land,” she says.
Project designer, Dan Prochazka says a challenge with design was a big tree in the yard Grosser wanted to retain.
“I was given a pretty complex design brief. It wasn’t in an open green field.”
He says constraints to design can be a “good design stimulus”.
“With 10 balls juggled in the air, how would it all come together?”
Once the basic structural design was agreed, the passive design elements needed to be incorporated, including ventilation with fans, purging after hot days with windows and stack effect, having thermal mass internally, and creating an unconventional brick floor tied to Geelong manufacturing and red brick history.
“I probably spent at least half a day sketching out the louver system, including the sun angles, and it was tricky because of the geometry – I’m quite happy with how it turned out.
“As a fixed system it will weather well.”
Prochazka says it was complex “playing around” in the architectural design tool to create drawings for the engineers.
“They put in a lot of structure that I didn’t intuitively guess,” he says.
“It took more time than I’d expected to then modify the drawings to meet the engineer needs.”
Duff Swanson from Restoration Carpentry says he has been working for green builders for about 10 years, and the project gave him the opportunity to put into action all he’s been learning and thinking about over that time.
“To have a client who knows about this approach makes it easy as I don’t have to convince Vicky to do things the way they’ve got to be done,” he says.
He says it’s nice to work on a project where so much thought has gone into the materials.
“Most tradies don’t have the luck to work with people who put dollars where their heart is. I couldn’t bring myself to work for volume builders and I feel for people who have to do it.”
Grosser says the project is having an influence beyond its fence line.
Geelong Council is looking at it as an example of ideas that could work well with its New Settlement Strategy. The builder, who initially found it challenging in terms of the extremely different design, particularly the roofline, has taken away green ideas that can be used on future projects.
Neighbours and other locals have given thought to whether they too would like a smaller home.
Grosser says there was also feedback from some of the trades, such as the plumber, indicating there is a lot of interest in being involved in a project where tradies can really use their thinking and skills creatively.
Her plan on final completion in a month or so is to host a barbecue and invite everyone from the entire supply chain over.
“There are all these brilliant people [involved] and they are the ones that often don’t get attention.”