Building a sustainable dream home with passive design

Building a sustainable dream home with passive design
Photo: Giovanni Gargiulo, Pixabay

There are several ways you can comfortably heat and cool your home without the added energy bill. Passive home design is a sustainable way to maintain a home’s temperature year-round without the need for conventional heating & cooling.

Relying on renewable sources of energy to power your house will maximise your comfort and health while minimizing your ecological footprint.

What is passive design?

Passive design is a sustainable building standard that takes advantage of the natural climate to maintain a comfortable temperature range in the home. Conventional heating & cooling systems account for about 40% of energy use in the average Australian household.

This results in increased energy consumption and higher power bills. A passive design home will reduce the need for energy, relying instead on the natural light and heat produced by the sun. This allows for sufficient heating during winter and cooling during summer.

Passive design homes take into account the local climate, landscape, and location of the sun to make the most of this renewable energy use and provide the most efficient climate control. By orienting your home on site or incorporating passive design features such as plant and window placement, you can minimise unwanted heat gain and loss.

Tips on designing passively

Good passive design in a home will achieve year-round thermal comfort, minimize your reliance on heating & cooling appliances, reduce your energy bills, and lower your greenhouse gas emissions.

The best time to incorporate passive design is during the initial building stages. However, you can renovate an existing home to incorporate passive design features to upgrade thermal comfort and reduce energy bills.

Orientation

Orientation is a crucial aspect of a well-designed passive home. By placing your home on its site to take full advantage of the sun and breezes, you will achieve greater temperature control and more out of your solar energy.

For example, in a tropical climate such as northern Australia, the ideal orientation of a home’s living areas would be to face north, allowing maximum exposure from the sun in winter, and shading of the walls and windows in summer.

Good orientation reduces the need for auxiliary heating & cooling, improving solar access to panels and using this renewable resource for lighting and heating of temperatures and water.

Insulation

Insulation plays a big role in how well your passive home will retain heat. Properly insulated walls, ceilings, and floors will help you to control the heat of your home and its thermal mass.

Dense materials such as concrete and brick are excellent at absorbing heat and slowly radiating it at night. To ensure none of this heat dissipates, insulation should be installed to provide all-year comfort and to maximise the performance of your passive design.

The most economical time to install insulation is during construction, but for an existing home, you can benefit from insulation retrofits or by making small DIY changes such as applying an insulation sealant or adhesive from your local hardware store.

Solar heating & cooling

Passive solar heating keeps out the summer sun while retaining the winter sun to ensure the interior of your home is always at a comfortable temperature no matter the weather. Passive cooling works the same way by utilizing the sun and natural wind paths to keep the home cool during summer.

Strategic shading, as well as the placement of plants and trees, can also help to passively cool your home. To be effective in both passive heating and cooling techniques, the orientation of the home is vital.

This allows the home to benefit from the natural path of the sun as well as the natural cross breezes through cross-ventilation. Passive solar heating and passive solar cooling is the least expensive way to heat and cool your home and is also the most sustainable way of keeping your home comfortable with minimum impact on the environment.

Windows

Windows are often the main culprit behind excessive heat gain or loss. Because of this, the placement of your windows will play an important role in effectively heating and cooling your home. Ideally, in the planning and designing phase of your home, you should arrange windows to optimise thermal resistance.

Locating and sizing windows to let maximum sunshine in when it’s cold and excluding it when it’s hot through effective shading via shutters, awnings, or double glazing will maintain proper airflow and heat retention.

Weatherproofing

Ensuring your home is weatherproof to resist harsher climates and conditions such as rain, hail, wind, and snow will protect your home from damage while keeping the interior climate comfortable. If you are located in a cooler climate or an area frequented by rains or susceptible to flooding, quality waterproofing is essential.

Not only will this keep water from leaking into the foundations and damaging your home, but it will also strengthen the structure of your home and allow its passive design to be fully functional and successful.

Passive design principles take advantage of the natural environment and climate to maintain a comfortable temperature range in your home or building. This reduces the need for auxiliary heating & cooling systems, which results in lower energy bills and a reduced carbon footprint.

Final remarks

Through passive design, your home will maintain year-round comfort and reduce running costs through the use of strategic orientation, insulation, renewable energy use, smart window design, and proper waterproofing.