10 Star Energy Efficient Homes: Affordable for Everyone

We have been awarded the Housing Industry Associations highest accolade for the 2015 Greensmart Energy Efficiency Home of the year - and we are so proud!

Two years ago we had a lovely couple, Ann and Alison, request an energy efficient home for their property in the country. "We want to live as much as possible of the land and with minimal energy use. We want a home that is beautiful, low maintenance and stands the test of time".

Ruby, our practice manager, and I met with Ann and Alison one sunny afternoon in Spring and talked about the site, their needs and the principles of energy efficient design.

Solar Passive

We started with the principles of solar passive design:

  • Orientation to let Winter sun in to living spaces and exclude sun in Summer.
  • Well insulated to hold Winter heat and Summer coolth.
  • Eaves that assist with sun access management.
  • Southern verandahs to cater for the interface between the land and the home.
  • Thermal mass in the walls and floor to keep the temperature of the home interior more stable.
  • Cross flow ventilation in the beautiful Spring and Autumn months.

Passiv Haus

Where Solar Passive deals with orientation, sun access, insulation and thermal mass, "Passiv Haus" deals with the technology of stabilising temperature.

  • Fully sealed windows, doors and a complete building envelope with a membrane to prohibit air movement except through a filtered, heat exchange ventilation system in the extremes of Summer and Winter.
  • Triple glazed, thermally broken windows and doors that seal shut like a fridge door.
  • A heat transfer system that retains coolth inside the house in Summer and heat inside the house in Winter and allows an exchange of filtered air that excludes dust and fog and allows the house and inhabitants to breathe.
  • A thermal break beam that runs the perimeter of the house at the junction between the slab and the cavity brick wall insulation.
  • A membrane that allows moisture to move from inside to outside, thereby preventing condensation, but ensuring that the air is kept stable inside the home.

The effect of combining Solar Passive principles and Passiv Haus technologies has enabled the energy efficient rating to go off the chart.

The current energy efficiency software used in Australia, does not fully recognise the benefits of Passiv Haus technology so we could be achieving an even higher energy efficiency rating without knowing.

Added to this is a return to grid solar photovoltaic electricity system and large water tanks for fire management and use in the home. A waterharvesting system is due to be implemented that will capture the rain water and grey water to feed underground channels where water is stored amongst the roots for trees and plants. This extends the growing capacity due to the increased moisture content in the soil all year round. 

This is a wonderfully sustainable home.

A big thanks to Wayne Torres and his fantastic team of builders, tradespeople and artisans for creating a magnificent level of quality and for persevering with the fully wrapped membrane within the house structure that required every single joint and penetration to be sealed. Great job.

Thankyou to Gino Monteleone for crafting a beautiful Redgum kitchen and plywood and bamboo joinery throughout the home. Gino also made the front door to suit the German window system technology, required for the Passiv Haus standards. The cabinetry work is exceptional.

Finally a big thankyou to Ann and Alison for dreaming the dream and and sharing a wonderful journey!

Thanks,

Paul Barnett

 

For more photos and information on Carwoola House, click here.

The Living Pod

One of the many challenges all ages of people face today is having ownership of their shelter.

The system of creating and owning homes has been variably driven by a model operating since the early part of the 1900's.

  • Land availability
  • Sub-division and services infrastructure
  • Development guidelines
  • Bank finance
  • Stable work force and long term employment
  • Developer Design & Construction

In the 1960's and 1970's a house cost around 2-3 times your annual salary. You could buy it on one income. Houses were smaller, there was less consumer product, materials and resources were affordable and plentiful, and there was plenty of land and water.

Now, nearly all the these parameters have been inverted:

  • Land is scarce
  • Affordability: 10 times the annual wage to buy your home
  • Resources are expensive
  • House sizes are expanding to align with land and infrastructure costs,
  • Multi-unit development as a response.

The net effect is that we now have:

  • Young and old unable to afford homes.
  • Housing stock that suits a "traditional husband and wife with two kids and two cars" but does not support the diversity of social groups that exist in our community.

The housing models fail to align with our broad section of cultural values:

  • Environmentalism: protecting and enhancing the natural world,
  • Affordability
  • Proximity to social hubs
  • Housing type diversity
  • Access to nature and gardens
  • Stewardship of our earth.

As an architect running a medium sized practice, I have observed the changing requirements of family dynamics and the responses to change over time.

We are asked to help solve social patterns via habitat design where most of the design decisions have been made by developers, planners, many years ago which leaves a narrow space to evolve new housing typology that fits with the now and responds to future needs.

We are aware of what is possible and how current technology and design offers:

  • Solar passive design
  • Passivhaus design
  • Insulating materials
  • Triple Glazing
  • Building wrap membranes
  • Photo voltaic technology
  • Heat pumps
  • Heat exchanger ventilators
  • 3D building modelling systems
  • Thermal break wall, windows and door systems.
  • 3D printing of building materials and components.

These are all available to utilise and create environmentally friendly, low energy using habitats.

We have mapped the range of social patterns requiring accommodation and they cover:

  • Simple family: adults and young children
  • Couple with no children
  • Mature family: adults, young adults and grandparents
  • Group house: students and friends
  • Single mature adults
  • Unemployed
  • People with disabilities

The diversity of social patterns requires a response that caters for this diversity and one possible solution is what we call the "Living Pod" design.

On a single house block as old houses become obsolete and new land becomes available, it is possible to create a multi-pod home that caters for all social types and circumstances to exist at any time.

Planning wise, imagine a four leaf clover with each leaf being a separate self contained habitat with bed space, living space, kitchen-dining space and wet area.

These spaces may be as small as 10m2 and up to cater for a range of inhabitants from a teenager to young adult, studying, working, or creating their own employment and want to pay minimal rent, to larger multi roomed pods that cater for several adults and children.

A central atrium space provides an airlock/garden/food production/air filtering/environmental attenuating space, enabling access to all living pods and a communal safe space for all ages.

The type of development we are proposing utilises water harvesting and permaculture to significantly enhance the natural environment, filters water and increases summer shade with deciduous trees and provides a central natural garden for the entire community on the site.

Buildings utilise the latest technology for environmental management, store water, produce electricity and are built from all renewable resources - wood, natural finishes, etc.

The aesthetic is natural, organic and beautiful and enables all aspects of community to function.

It is a real paradigm shift in residential design.

Sustainable Natural Landscapes

The beautiful thing about emerging natural landscapes is they just get better and better as plants mature, moss grows, animal and insect life move in, more mobile birdlife appears and the natural rhythms of growth and decay harmonises. That's what we are creating!

Our work with natural landscapes started some 20 years ago when we were introduced to Permaculture, Biodynamic Agriculture and Waterharvesting. I was always interested in nature and these areas of interest grew out of a natural love of nature.

What is it all about?

We are taking compressed soil areas, with no water retention and little ability to support plant life and converting them into a lush oasis that utilises water harvested from the roofs of adjacent buildings. The water is then stored and distributed throughout the landscaped area.

We remove the compressed soil, terrace the landscape to capture rainwater, reverse the water runoff and allow the water to seep into the ground. The waterharvesting channels are placed like arteries of a body through the ground, which feeds moisture to all the roots of our new environment.

Dry laid rocks are used to form the terrace and provide a natural haven for animal life, such as geckos, lizards and beetles. They provide a place for creeping plants, succulents and ground covers to take root and benefit from the coolth in summer and the moisture emerging from the waterharvesting trenches.

Then we condition the removed soil from excavation by adding soil improver and natural biological solutions that are found in normal healthy soil. once improved, the soil is placed back into the terraced structure, that is now fed with and retains water.

Trees are planted around 1 every 10m2 and grow to become a canopy that provides an understorey in summer for the next layer of plant and animal activity to be created. In Canberra, we are mostly using deciduous trees to shade the dry summer months and open the understorey to light and sun in winter. a bit like a solar passive house in nature.

We have environments that were created over 20 years ago by the original developer of waterharvesting Paul Totterdell and supported by Tim Edmondson, who worked extensively at the Rudolf Steiner School, that have now reached maturity.

These environments create havens for small bird populations that can struggle to find protection in an urban environment, where trees may be placed as a feature but not as part of a forest. Natural turns up when the right conditions are in place.

The wonderful thing about these landscapes that mimic nature, is that they seem to improve over time. The soil is kept moist as long as there is periodic rain, as the waterharvesting channels hold the water and allow moisture to spread out in the soil. After a few years, the tree root system finds its way to the channels and starts to mimic the shape of the trenches and forms a natural root channel where the water is taken up directly from the channel and feeds the trees and plants.

If the summer is a dry spell, the residual moisture in these environments lasts much longer than normal. Its only after a sustained dry spell that the smaller plants may need watering via the waterharvesting channels, thereby allowing the take up from the channel, rather than the surface. Even on a clear night, we see water enter the system from dew forming on the roofs.

We have been pooling talent and skills with Waterharvesting, Horticulture and Landscapes Consultants and have just created the first of many stages of Sustainable Natural Landscapes at the Aranda Primary School in Canberra.

We started with a barren area of concrete, asphalt and dirt with about a 4 degree slope. There had been trees in this area, but they had died over successive years of hot summers, due to the lack of water absorption and high run off due to compacted soil. It was a hot area in the centre of the school and surrounded by roofs. It is a perfect setting for the Sustainable Natural Landscape approach.

This area is about 20mx50m in size and was recently completed.

The natural environment that we created now has about 60 lineal metres of waterharvesting channels, 150 tonne of rock, 32 trees, over 100 plants, 2 x sand pits, 1 x bark play area and over 200 lineal metres of rock terracing seating. Eventually, this area will be mostly shaded in summer and a haven for ground covers, plants and small ground animals that can be studied and enjoyed by the school students.

Aranda Primary School has started running Art Classes in the landscape and we are currently preparing to present the design strategy behind the Nature Landscape to teachers and school children, so that they may study its evolution over time.

We are bringing nature and life to the areas that were barren. It's like a magical transformation. Everyone enjoys the emergence of so many trees, rocks and life.

Stage 3 has just begun at the school and we are currently planning to save their ovals with the same design system, but which will nourish their play areas and extend the life of grass areas.