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Gaining heat from the sun
The home has been designed in a modified “T” shape. It is positioned on the northeast-southwest axis across the site, with the living areas (including living room, dining room and shrine) positioned across the long axis of the house, facing north-northwest (precisely off north 18°).
Large windows and sliding doors open onto a large timber deck on this NNW side. As the sun rises from the northeast quadrant and sets to the northwest quadrant during the winter time, by facing NNW, the living areas can gain more sunlight in winter.
Furthermore, with a calculation of the sun angle, a wider (1.6m) eave outside the living room as well as a pergola outside the dining room were designed to avoid overheating from the high summer sun and allow low winter sun to enter (to gain solar heat).
Storing heat from the sun
Alongside the windows/doors in the living and dining areas are a row of floor tiles, with an underfloor 100mm concrete slab which acts as a thermal mass as well as 50mm expanded polystyrene which acts as a thermal bridge barrier, to store the sun’s warmth and release it later in the day.
Keeping the heat inside
Recycled wool is used as insulation for ceilings (R 3.0) and walls (R 2.2), expanded polystyrene is used as insulation for concrete slab floors (R 1.32), as well as using thermal drapes closely fitted at the pelmet as insulation for windows, to form an envelope of insulation around the house. An airlock at the entry and draught stoppers for doors reduces the heat loss.
Moving the heat around
In winter, with 5.4m high sloped ceilings and closed double glazing clerestories, a reversible ceiling fan is used to move the stacked heat, produced from the wood burner and passive solar gain, around the living areas. With the help of a heat transfer kit transfer, warm and dry air is circulated to bedrooms.
Barrier-free, nature lighting & nature ventilation design
The house has no thresholds or internal steps, but has an easy access from the garage via ramp. Doorways, entry points and hall ways are wide enough for disabled access.
With the modified “T” shape house design, more edges were created, and every single room (even storage and garage) has large windows. There is no artificial lighting required during the day.
As a thermal chimney effect, high windows in the living room are able to be opened to let warm air to rise by convection and escape outside. At the same time cooler air can be drawn in to naturally ventilate the house.
Solar water heating
A 2.6㎡ all-copper flat plate collector panel was mounted on the sloping north-northwest-facing roof while a 200L vertical solar and electrical water heating cylinder was set on the floor of the garage. This solar energy system can generally provide all our hot water needs for washing and bathing in summer, and we use continuous gas booster as a winter backup. To prevent freezing in winter, the system uses anti-freeze fluid instead of water as heat transfer fluid. | 
