SELECTING THE CORRECT ORIENTATION
The orientation of your block plays a huge role in your eventual home design- much greater than what many would think.
Good orientation increases the energy efficiency of your home which in turn is both a huge step towards more sustainable housing, as well as a large reduction in the running costs of your home. With rising energy costs once again a hot topic of discussion, it seems a logical step to optimise the location of your house on your block, especially considering that optimal house orientation costs you no more than a little additional upfront thinking.
Additionally, a well designed, well orientated house is much more comfortable to live in during both summer and winter. In summer, a well oriented house is kept cool by minimising the heat gain into the house and capturing cooling breezes. Whilst in winter, a well oriented house is kept warmer through allowing the winter sun into the house and preventing any heat loss.
One of the most important aspects is the orientation of the block itself. When selecting a block, you ideally want it to be elongated along the east-west axis, therefore having a larger north facing boundary. This increases the ability to maximise the homes northern outlook. In return, this means more rooms and windows facing north, and subsequently, the ability to capture and store the greatest amount of winter sun and heat.
Along with the orientation, the current built environment should be considered when looking to purchase a block of land. Any existing buildings or trees to the north, no matter how small, will shade some portion of the north face of the house and will therefore dramatically affect the homes overall performance.
For instance, a corner block with an uninterrupted north face will work very differently when compared to a block with a three storey house in close proximity to the north face. Both blocks may be elongated on the north face, however, the corner block with no overshadowing from any surrounding structures will provide a far greater end result than the block being overshadowed by the three storey home. During the winter months, the sun is at a much lower angle, so even a small obstruction to the north face can be quite detrimental to the function and operation of the house
Similarly to how the built environment plays a role with capturing the winter sun, it also greatly effects how the cool summer breezes are allowed to flow throughout the home (in Perth commonly referred to as the Freo doctor, or Fremantle doctor). These cooling sea breezes come from the South West, providing a cool relief to our hot Perth summers. Wind paths are a little more flexible than the sun as these breezes can be manipulated and guided with wing walls and wind tunnels. However, if you have a large obstruction (for example a large house or apartment complex) in close proximity to the south west of your house, possibly even abutting your house, it will effect the ability to capture these cooling summer breezes.
As you can see, it is not as simple as only looking at the overall orientation of your block, but also the surrounding built environment in terms of how it will affect your home design.
A good designer that has the ability to think outside of the square can work in with any scenario to make the best of both the block orientation and built environment.
Stay tuned for our next post in our mini series on Passive Solar Design.