You can see the evolution from Peter's original drawing (above) to the more detailed plan below. We have now included a bathroom in the house (rather than use the existing external building), a greenhouse to the north of the bathroom, a carport to the east and shifted the extension to the west. All of these changes will add to the final cost of the project.
The water tank to the right of the plan will sit above a cellar, made from the bricks that I have collected. The tank will assist in the cooling of the cellar by providing cool thermal mass from above. The cellar will sit 1.5m into the ground and .5m above the ground, giving the tank a small head for gravity fed watering. Inside the cellar will be an inlet for the cool cupboard. An underground pipe will run from the cellar to a cupboard in the kitchen, drawing cool air from the cellar through the cupboard. This will reduce the need for a large fridge and cut down on energy bills.
The bathroom will have a solar hot water system situated directly over it, so that less piping is needed and heat loss is reduced to a minimum. The pitch of the roof over the bathroom and greenhouse is at 30 degrees, so that the solar panels can mount directly onto the roof without the need for a mounting frame.
The house will be raised 800mm above the ground (a requirement because of the risk of flooding), giving a good amount of head for the reuse of greywater. I have been investigating a DIY system whereby all the greywater is fed into a worm farm, then a reed bed, and later a pond in order to clean and store it for reuse. The worm farm may sit under the bathroom or to the east of it. While a toilet already exists in the existing building, I would like to include a composting toilet in the new bathroom in the future. Because the building is raised off the ground this should be quite easy to install.
A treatment system that looks very interesting (if I had the money) is Biolytix, which uses living organisims to break down 'waste'. It can convert all black and greywater into nutrient rich water that can be re-used for irrigating plants. I think that it would be great to sit a toilet seat straight over the inlet.
The greenhouse, to the north of the bathroom will help to regulate the temperature of the building, with window / vents that can be opened and closed as needed. It will also provide an interesting view from the bathroom and a microclimate for growing plants outside their normal season / environment.
When I lay the site analysis over the plan (which illustrate some of the patterns of nature) you will notice that the direction of the cool winds 'funnel' into the entranceway. This will be used to help ventilate the house during hot weather, and will be addressed in the cold weather by having a lower ceiling in the entranceway, matching the low roof of the carport (not on current drawings). There is also a large pear tree that will offer some protection from those winds.
The house does make the most of the winter sun with windows on the north allowing in the sunlight, heating the insulated concrete slab in the living area. Eaves will prevent the sun shining into the house during mid summer, and the slab will draw coolness from the earth below. The deciduous apple and elm(?) trees to the north of the living area will be retained, offering summer shade and the light to penetrate in winter. A cherry plum will be retained to the east of the bathroom for aesthetic reasons (it was the home of the nest with the eggs).
The 'primary noise sector' is buffered by the living area, in which windows will be double glazed. Hot summer winds will be deflected somewhat by the fence and 2.7m high brick wall of the neighbouring block on the northern boundary.
The view of the creek will be taken advantage of by the small sitting area at the entrance and the windows from the two main bedrooms, but the house is not really making the most of this asset in this design, as the living area faces the north.
While it is important to keep costs down in the building of the house, I'm also thinking about the running costs of the house. I want to create a space that makes the most of the natural elements that surround it, embracing them. This house will become a living, breathing entity.