The passive side to solar

Beyond simply saving money, what if you could keep your house warmer in winter and cooler in summer? Being able to substantially reduce the amount of heating or cooling you need in your home, can be done by incorporating some simple design features?

Passive solar design is all about keeping the temperature within your home steady all year round utilising natural sources of heating and cooling. Harnessing your local climate to passively achieve thermal comfort, will reduce the need for heating and cooling appliances which, according to the Australian Government Your Home website, can account for a whopping 40% of your energy use.

Maximising your power.

In a previous article, we talked about sustainable house design factors, let’s now take a closer look at passive solar design for new builds and some things you can adopt for if you have an established home.

1. Understand your climate.

“A true passive home is a constant temperature, but doesn’t require you to actively manage that temperature level,” says David Berryman from Green Homes Australia.

“It’s important to understand the climate you live in; obviously people living in Queensland will have different home design considerations to home owners in Melbourne or Tasmania.”

2. Think about thermal mass.

Materials with a high thermal mass include concrete, masonry, stone and rammed earth. These are dense and can store heat within. The capturing of heat in thermal mass is best suited to climates with sunny days and cold nights.

“A great design feature to think about is the principal of thermal mass in your home in the form of an internal wall,” adds David. “Positioned in a northern facing room, it will absorb heat, creating an energy bank that will slowly release warmth. It doesn’t have to be ugly, rendering the wall will create a living area feature.”

3. Remember to draft-proof and install a heat-recovery ventilator.

David says that draft proofing is often overlooked in homes, but is really important as up to 20 per cent of heat is lost through draughts through your home. Draft proofing is a great way to help established homes, as well as something to consider when you’re building or renovating.

“For instance, simply sealing the gap between your floor and skirting boards can really cut heat loss.”

4. Install solar panels.

Installing solar panels on your roof is just one part of the equation, says David, but it’s something both existing and new homes can benefit from. Solar is at its best when energy consumption is required during the day.

“Incorporating these design elements in the early stages of your home build or renovation will create a home that is truly passive.”

For existing homes, it’s also a good idea to adopt these strategies to be on your way to a truly passive solar home, to help trim your energy bills and keep your home naturally warm and cool in tune with the weather:

  1. Effective shading. Direct sun can generate the same heat as a single bar radiator over each square metre of a surface. Planting lush trees on the western side of your home to shade the walls and windows during the hottest part of the day is a wise move.
  2. Check your insulation. It can also help with weatherproofing and soundproofing, and help cut your energy bills.
  3. Install a skylight. It can provide up to three times as much natural light as a vertical window but consider your climate, as the skylight can admit a lot of heat in summer.
  4. Explore heat recovery ventilation options. Especially if building or going into renovation mode.