Jane Troughton and Greg Courtney’s green home in Durban north, Kwazulu-Natal, is the triumphant culmination of years of research and exploration into sustainable life. Aptly named Gorgeous Green House, it is a finalist in the 2015/2016 AfriSam-SAIA Award for Sustainable Architecture + Innovation, the winners of which will be announced on October 27 2016.
The couple bought a traditional 1940s bungalow with the intention of renovating it to be entirely sustainable – reusing, recycling, selling and gifting to others any surplus materials wherever possible. This commitment extended to the plant and tree life. Troughton started a blog to detail the triumphs and mistakes of their journey towards sustainable living.
Chen Sagnelli of Sagnelli Architects sums up the client’s design brief as a house with a minimal simplistic feel, clean contemporary lines, and a strong sense of indoor-outdoor living. It is a simple structure subservient to the natural environment; every room is designed with a connection to the outdoors.
The home is contemporary, entirely suited to the South African climate, the green technology is invisible, and any sustainable or recycled materials are either indistinguishable from their counterparts or stylish in their own right. Such as the bamboo kitchen units and a 60% recycled kitchen countertop, top-notch soft-pile carpeting using recycled plastic bottles, and quality eco-paint.
Elements of the existing house were retained and often repurposed. Materials such as Oregon floors and slate roof tiles were sold, while doors were fitted elsewhere on the property, lifted slats to became garden paths and all bricks were reused.
Sagnelli says: “Building a green building isn’t just a matter of assembling a collection of the latest green technologies or materials. Once the design is honed, then the impact and interrelationship of different elements and systems within the building and site need to be re-evaluated, integrated and optimised as part of a whole building solution. This integrated design process mandates all of the design professionals work cooperatively towards common goals from day one.”
He gives an example: “The interrelationships between the building site, site features, sun’s path, location and orientation of the building, and elements – such as windows and external shading devices – have a significant impact on the quality and effectiveness of natural day lighting. These elements also affect direct solar loads and overall energy performance for the life of the building.”
GREEN WALLS AND ROOFS
James Halle installed the vertical garden of cliff dwelling plants at the home’s entrance next to the formal water pond alongside the entrance walkway. “The vertical garden is a hydroponic system – water is pumped to the top and then slowly seeps down through the fabric. It’s not just to display plants on the vertical, but to create a diverse habitat,” says Halle. Troughton was involved in the installation, and the ongoing maintenance.
Troughton was determined to have a roof garden. The architects suggested it should sit on the full length of the lounge, which means upstairs, the main bedroom en suite is vast. Expansive glass doors slide back to open the bedroom-cum-private lounge on to the roof garden.
Beyond the roof and walls, the rest of the garden includes a veggie garden, beehive and four worm farms, and chickens.
HEATING AND COOLING
“A roof garden also has excellent thermal properties,” says Troughton, “so it’s a way to keep the house cool and reduce energy costs.” Designing to accommodate airflow and temperature is critical. “We didn’t want air-conditioning or heating, so it’s all about the ventilation. In summer, the floor level windows on the south side are opened, drawing cool air across the pond and up into the house. Windows above eye level aid in cross ventilation, and a series of whirly gigs suck out hot air. The deep veranda also keeps the interior cool.”
The house’s north face has an aluminium facade of alternating louvers and decorative panels. Troughton designed the “generic leaf pattern”, which softens harsh lines and materials, and cuts the glare; shadows and reflections cast by the leaves on to the reflective windows and the floors.
This facade forms a backdrop for the chemical-free swimming pool. The water is pumped to the top, and moves down three waterfalls – or reed bed elevations – filtering as it descends. Each level contains different plant material. “In an eco-pool, you need specific plants. Your floaters – water lily-type plants, and sub-aquatics – reeds and papyruses; each have different cleaning functions,” explains Troughton. “We have fish, crabs and herald snakes hunting here are night!”
Throughout the home water is reused, and there’s a 20 000ℓ underground water harvesting tank. There’s a compact grey water unit camouflaged in – and used for watering – the garden.
The house generates sufficient energy for the family’s needs, but remains grid tied. Troughton explains “I’m lobbying for the municipality to honour their power purchase agreement with us so we get paid for the excess – if people can see that their investment in alternative power will pay back quicker, they’ll be happier to invest.
“We used to spend R2000 a month. Somewhere between 2018 and 2019, we will have saved our investment in solar, depending on the expected increases of between 12,2 and 25%. Thereafter we are free and clear,” says Troughton.
THE GREEN CHALLENGE
Troughton doesn’t believe it’s any tougher for South Africa’s construction industry to build a sustainable house. But what has surprised her – and was one of the drivers behind creating her blog – is the difficulty of accessing green products.
The major lessons learnt on this journey were numerous. “Do loads of homework before you start, so you’re clear on your goals. Also, confirm the supply of materials. Don’t expect your architect or builder to know green – interview your service providers beforehand.” On essential elements, she says: “Passive design is vital, never opt for cheap when selecting technologies around your water and electricity, and choose plants and a roof garden for insulation, not to mention beauty, wildlife, joy and happiness!”
By ANNE SCHAUFFER; Photography by GRANT PITCHERThe full article appears in the Oct/Nov 2016 Issue 34 of Earthworks Magazine, pp 28 – 36