Building Brief
|
We
hope to build a sustainable, healthy and energy efficient house.
|
|
|
The
sustainability of the house comes mainly from the choice of building materials
which have the least effect on the environment. Such materials include
those that
|
|
|
a)
have low embodied energy in their manufacture
b) are sourced locally c) have been recycled d) come from renewable resources |
|
|
By
'healthy' I mean a house which is built, as far as possible, using natural
materials and avoiding the use of synthetic building materials, finishes
and furnishings which release or outgas pollutants or have other adverse
health effects.
|
|
|
Energy
efficiency can be achieved by designing the house using passive solar
principles. The energy required to heat and cool the house can be minimised
by
|
|
|
a)
orienting it along the East- West axis
b) providing sufficient thermal mass c) providing sufficient insulation d) orienting daytime living areas to the north side of the house e) having sufficient north facing windows f) avoiding windows on the East and West g) minimising the size of South facing windows h) shading all North facing glass with sufficiently deep eaves i) encourage cross-ventilation in summer with low South openings and high North openings j) cooling summer intake air with a fernery/water feature on the South k) grouping areas where hot water is needed |
|
| However, we are not zealots and realise that compromises must be made. | |
| Firstly, we wish to build a pole frame house with mud brick, despite its ‘apparent’ poor insulation value, mainly because we love their feel and the look. I say ‘apparent’ because, although mud brick has a relatively low R-value, the R-value does not take into account its thermal lag that greatly slows any heat transfer across it. Mud brick also has a high thermal mass which can more than compensate for the low R-value. All the mud brick houses I’ve been in have felt comfortable in both winter and summer, although some, with poor orientation, have required heating in winter. There must be some reason that people have been building adobe buildings in desert climates for thousands of years. Furthermore, mud bricks have very low embodied energy and can improve internal air quality because they breathe. | |
| Next, I’ve always wanted to build a house with a loft or mezzanine overlooking the living area. This may cause some draughts that reduce efficiency in winter, but could improve efficiency in summer by creating a thermal chimney. | |