Designing to suit our subtropical climate

If you want to build an energy efficient home you should consider using passive design principles. It would help reduce the utility costs by helping save energy and water. Also it would reduce the costs in the long run through lower electricity and water bills. However it is important that the home’s new design is in correspondence with the climatic South East Queensland weather. It is a subtropical climatic zone with the following characteristics:

  • The weather is fairly humid with occasional spells of dry season as well
  • Temperatures are high the year round except for winters which are slightly milder
  • There is minimal seasonal temperature variation
  • Rainfall in this area is above average

If you are considering building or buying a new home there are certain measures with would ensure your home is not only comfortable to live in but also has a low impact on the environment. Energy efficient homes are economical to run and are actually adaptable to the changing needs of the millennials.

When building for a subtropical climate care should be taken that the homes require a minimal amount of heating and cooling. During the preliminary design stage you should be mindful of the following:

  • The northern side is always warmer during winter and is normally the best place for rooms which are used on a regular basis like the living area or the outdoor decks.
  • The west side of the home usually gets pretty hot during the afternoons and would be ideal for building bathrooms, garages and laundries.
  • The coolest zone is the South side. When constructing your bedrooms as well as rooms where you need loads of peace and quiet, the South side should definitely be considered.
  • You can get all the morning sun that you need when your breakfast rooms or the kitchen is placed on the east side.

Importance of cross ventilation

Make sure that you choose high level windows or ceiling cavities which would create stack ventilation. This would allow the hot air to escape and be replaced by the cool air. The building shape and orientation of the home would have an impact on the air circulation. The windows should be placed in such a way that would pick up the prevailing breeze and improve cross ventilation.

The orientation of your home

For the subtropical climatic zone a northern orientation for the living area and outdoor spaces is considered to be the best. The house design should shade potential high heat loads from the south east during summer mornings and the south west during the afternoon.

During winter the solar access needs to be maximised so that maximum heat can gain entry into the homes. If you have used bricks, concrete floor and tiles to build the home the heat absorbed during the day can be released at night so that the house remains warm.

During summer the home can be protected from heat gain with the help of vertical shading screens and blinds. The use of insulation on the floor and the walls would create a stable internal temperature  during the summer and the winter months.