Sustainable House Day, Narrawong, Victoria

Thornbill Organic Farm - Narrawong

The existing bluestone/timber home on 10 acres has been retrofitted to maximise thermal mass and northerly aspect. The house and garden layout are  central to the reduction of all energy inputs in relation to shelter, food and water for this family home and small business operation.

Climate zone: Cool Temperate

Unique Sustainable Elements featured in this home

Water Harvesting Systems
The house and shed roofs collect rainwater which fill three poly tanks totalling more than 40,000L.  This supplies water for all the household drinking, cooking and washing needs across the year.  The annual rainfall is on average 700-800mm annually.

A dam, holding approximately 600,000L, supplies all the water to the toilets and garden areas.  Dam water is first pumped to a small storage tank where it is then gravity fed into the irrigation system.

Grey water from the house filters through a gravel/reed bed system, then on to sub-surface irrigation of fruit trees.

Special Garden Features
The garden/whole farm layout incorporates all the key elements of the Permaculture Design Principles.  A large vegetable garden is surrounded by a food forest of decidous fruit trees (predominately apples) and berry shrubs.  Chickens and ducks supply eggs, meat, manure and pest control and are an important part of the food garden operation.  Sheep also rotate through a three-paddock setup.  A wood lot is being developed and native vegetation has been retained and regenerated.

In addition, the farm has been designed and operates as an environmental education centre. As a result, for example, compost bays and worm farms are easy for the family, as well as groups of students, to access.

External Walls
The ground floor is built entirely of locally quarried bluestone. The second story is bluestone on the east and west walls and cedar on the south.

Sheds have been constructed from recycled corrugated iron and recently reclad with strawbale and render.

Timber frame windows are used throughout the house.  Recycled windows were used for the second stage of construction (lounge and second floor).

Internal Walls
Internal walls are predominately pine stud frames clad with pine lining board.  Some walls are natural bluestone with no lining or internal framing.

Roof
Ground floor has cathedral-like celings with unusal angles in the kitchen area.  The second floor has clerestory windows which meet a steep roof on the north side to form the upstairs ‘wall’.

The roof is made from corrugated iron.

Floors
The ground floor is a concrete slab.  The lounge/family areas and two bedrooms are carpeted with thick underlay.  The kitchen has cork tiles and the entry ceramic tiles.  The second floor has pine floorboards.  The study/storeroom and spare bedroom have bare concrete floors.

The study with 3 walls of bluestone, a concrete floor and southerly aspect also acts as a cool room for preserves, wheat, beer, wine, onions and garlic.

Solar Power Generation
A 1.1kW grid-connected solar array provides enough energy for all of the family’s electricity needs in summer.  The solar energy system provides approximately 1/3 of the household’s energy during the winter months.

Heating and Cooling
The bluestone walls and roofing insulation mean that no artificial cooling systems are required.

Heating is via a wood heater with electric fan.  Raw firewood is sourced entirely from within the property boundaries from fallen limbs and woodlot.  Recycled timber ‘smalls’ from shed demolitions on nearby properties also provide fuel for the wood heater and external wood-fired oven.

Water Heating
Two panel flat plate solar heating with off-peak electric booster.  The electric booster is used from late April – September.

Recycled and/or Sustainable Materials
Bluestone, the main construction material, is low in embodied energy.  The bluestone quarry is less than 20km from the house site, keeping transport costs and emissions very low when the house was first constructed.

The shedding is constructed from recycled corrugated iron, an off cast from a local school roof replacement.

In relation to strawbale cladding of shed walls, it is important to note that the straw is a ‘waste’ product of the wheat industry.

Going Forward
This house and farm is designed to provide a family with all their daily needs as well as derive a small income from the education centre and excess produce.

For more info go to www.thornbill.com.au