Harnessing the Sun: Passive Solar Design in Illawarra's Climate

Wouldn't it be great to have a home that's comfortable all year round without depending on heating or cooling systems? One that can cope with the scorching heat of an Australian summer just as well as freezing winter nights? That's exactly what you get with a passive house.

Having a passive house is all about making it work for you so that you don't have to worry about energy costs again. The temperate climate of the Illawarra lends itself to the use of climate-responsive, sustainable design principles that can see a home using little to no power for heating or cooling.

So, let's take a look at how to achieve a solar passive design that embraces the near-perfect climate of the Illawarra.

Why Is It A Good Idea To Embrace Passive Solar Design?

Around 40% of household energy use goes toward heating and cooling. Building new or retrofitting existing homes using passive design principles can help to achieve thermal comfort without relying on mechanical heating and cooling systems (or using them only a small percentage of the time).

Whether you choose to have your new home fully certified as a passive house or to only incorporate a handful of passive design principles for reduced power bills, building a home now that can cope with your local climate conditions efficiently is a wise investment.

Read more about A Class Building and Construction's Commitment to Sustainability here.

What Are The Key Principles of Passive Solar Design?

When it comes to sustainable home design, there are two key ways of thinking regarding using our climate to our advantage. The first is a passive house (or Passivhaus). The second is free-running design.

For a passive home to work, it relies on these features:

• An airtight building envelope where minimal air leaks in or out.
• A focus on high R-value insulation.
• A mechanical unit to bring fresh, filtered air is needed for exceptionally well-sealed homes.
• Doors and windows that reduce heat gain and loss with either glazing or by reflecting heat.
• Eliminating thermal bridging, where heat can travel directly into the house through structures like aluminium window frames.
• It may also rely on methods such as cross-ventilation to achieve comfort in the warmer months.

A free-running design uses these principles:

• Air movement for passive cooling. For example, positioning windows for cross ventilation.
• Shading to block out summer sunlight and minimise heat gain.
• Harnessing solar energy and solar techniques such as thermal mass, where materials absorb, store and release heat.
• An orientation that maximises winter sunlight and heat loss for passive solar heating.
• Lighter colours for roofs, windows, and walls, with shading from the sun.
• A focus on insulation.

As you can see from the above, there are several ways to approach passive solar design in a new home build. You might choose to follow all of the Passivhaus standards to achieve a particular level of performance and have your home certified.

Alternatively, you may decide to take a more relaxed approach featuring measures that allow you to minimise your reliance on mechanical systems for heating and cooling, combined with taking active measures to keep your house cool or warm (such as closing the shutters to keep heat out or embracing thermal mass by planting a deciduous vine to let winter sunlight penetrate a concrete slab and warm your home).

Incorporate Passive Solar Elements Into Your Design

From ventilation and insulation to smart architecture, you can incorporate passive solar technology to any degree and see the benefits in your home.

• Harnessing the sun's energy can be as simple as choosing flooring that helps with thermal mass, such as stone or wooden flooring, or powering your home with a sustainable solar system.
• Embrace technology to lower your impact on the environment even further. For example, a smart home system can control blinds even when you're not home. If the sun has suddenly come out, press a button on your mobile phone, and you could be using the power of sunlight and thermal mass to store heat for later in the evening.
• Carefully consider the orientation of your home to make the most of the sunlight. In the Illawarra, you want to locate living areas to the north and bedrooms and service areas to the south.
• Consider your environment and choose the most suitable materials for your home. For example, mud brick and natural stone provide thermal efficiency and a feeling of warmth, lowering your reliance on heating systems.
• Even if you build an airtight passive house, capturing breezes using vents and cross ventilation is still a fantastic way to forgo power-reliant cooling in summer.
• Simple measures such as awnings over living spaces and trees or trellises to shade outdoor areas can minimise overheating within your home. Choose flexible options such as deciduous vines and retractable awnings that let sunlight in when you need it.
• The placement of windows is critical for sunlight exposure and natural lighting. North-facing windows can help maximise solar gains in Illawarra's temperate climate. However, they will ideally need to be double-glazed to minimise heat loss in winter since up to 40% of a home’s heating energy can be lost and up to 87% of its heat gained through windows.

When It Comes To Sustainable Building, We Get An A-Plus

If you dream of a low-maintenance home that uses very little power and keeps its occupants healthy, take a look at these two recently completed projects by A Class Building & Construction.

The first is this home at Coledale which needed to be an energy-efficient home of the highest standard. Low VOC (volatile organic compounds) materials for insulation, flooring and paint were sourced to keep the home as healthy as possible and rainwater collection and solar power systems mean the home also has as little impact on the environment as possible.

Our Bundewallah project is an example of passive solar design at its best. From its orientation to its thermal performance, it was designed to embrace the climate and reduce its occupants' reliance on power for heating and cooling. We're so proud to say that A Class Building & Construction's attention to detail and commitment to sustainable building helped this project come together.

Passive Solar Design and Sustainable Construction Is Our Passion

If a healthy, low-maintenance home incorporating passive solar design is right for you, there's no better place to build it than the Illawarra, with its cool, temperate climate. And when it comes to getting the right team on your side to build your eco-friendly dream home, you can't go wrong with A Class Building & Construction.

As local Illawarra builders, we have decades of experience constructing homes in the region, including those that embrace passive solar design, energy efficiency and sustainable building methods. We're passionate about building high-quality homes and collaborating with homeowners to meet their specific needs, so give us a call today on 0414 183 503 to learn about the A Class difference.