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Sustainable House and Home

Sustainable housing, what is it?

Although easy to say, creating a truly sustainable house has a lot more factors to it than people first usually realize.

For starters being sustainable means looking at the house from a whole 'life cycle' perspective; i.e. from buying the land, through to development of the house, then living in it and finally what happens when it is destroyed..

Choosing a sustainable plot

In part this is assessing a plot on the basis of firstly the 'ease' with which a property can be built on it - usually the more difficult the build the more materials, effort, energy and ultimately cost is involved. This can be sufficient to make what looks like a viable sustainable build on paper actually fail in reality as the difficulties in the plot conspire to work against it.



So what should you look out for in particular?

• #1 is unmanageable slopes - these either require the house be built into the slope (with drainage issues) or the house be built above the slope (i.e. on a raised slab or stilts) again expensive and requires extra materials. Although not all slopes are bad, it really comes down if there is a point on the slope that can be easily developed.
• #2 water courses - any water that flows across the plot will need to be either managed or taken into account in the plans. Nothing like a downpour flooding the low floor to dampen one spirits. Again this need not be all bad, it could give you the chance to put in a dam or generate your own electricity if the flow is sufficient - just be aware.
• #3 solar visibility - a plot with a large number of trees or being directly overlooked by trees means reduced solar access. This will effect the ability of the property to gain from passive solar or from solar power or solar water heating.
• #4 Wide East/West line - can the plot support a house with its 'spine' running along the East/West line?  This is important for good passive solar access. You can do a multi pavilion build to get a lot of East/West line exposure - but that is more expensive than a single build.
• #5 Trees - too many old trees can make a building infeasible, as often they will be protected and the design will need to take set backs into account. 
• #6 access to amenities - basically if the plot is miles alway from anywhere, then that will require a lot of transport to occur to live there. This does not mean the only place worth living in is a city but needs to be factored into the thinking (i.e. you will need to plan your trips more).

The sustainable house design

We have already hinted above at few key points, namely passive solar and building orientation, but there are few more things you need to take into consideration:

1. Design around function matching comfort - i.e. have the rooms you use the most on the Sun side of the house and those you use the least on the none Sun side.
2. Design to allow different parts of the house to be closed off as needed when not in use.
3. Insulation - in order for passive solar to work your property must have a good level of insulation.
4. Solar water heating - if you have good sun access, design in an efficient solar water heater from the start.

Also, if there is an existing property on the land, and its orientation is correct and its of a sound build; seriously look at reusing it rather than just knocking it and building afresh. Done right this should save you money and reduce the environmental impact of the build.

More information on sustainable housing

• Keeping your home cool in Summer and warm in Winter for free
• Solar water heating, how it works and the options available
• What is Passive Solar?
• What is convection and how it effects your heating costs
• The importance of roof insulation