June 2014


Passive heating and cooling.

Nowadays it’s becoming more and more common to come across terms such as passive heating and cooling, thermal mass and solar bank. The idea of a passive house heating system is linked to green home designs, with thermal mass guaranteeing good passive heating and cooling. The truth, however, is a little more complicated.

Passive Home Heating & Cooling and Thermal Mass

Passive heating and cooling occurs when a building is appropriately designed and uses materials that absorb and direct hot and cold air to create a more sustainable home. Passive solar house designs ensure that only minimum heating and cooling is required to be comfortable year-round.

The thermal mass of a building refers to the way its materials reflect the ambient temperature of the environment around it and the degree to which they both resist and retain hot or cold energy. High thermal mass materials include stone, solid brick, rammed earth and concrete. These materials are slow to heat or cool but tend to retain that state for a long time and only need minimal energy input. For example, a stone floor in a north-facing room (with the right windows and eaves) will allow you to feel the warmth of the winter sun long after the sun has moved on. Conversely, on a hot day, the pipes running through the earth under your home can use the cool ambient temperature of the earth to cool you down without air conditioning.

Where it gets tricky is that merely having high thermal mass materials is not enough to have really effective passive heating and cooling. This is because the property of retaining heat or cold air can be ineffective if your thermal bank is:

  • Not isolated properly in one zone
  • Not connected to the area you want to transfer the heat to

There are a number of passive heating and cooling home design features that a builder can incorporate into your home design. Some of these include: 

Rammed earth

Rammed earth is a sustainable material and a great thermal bank that relies on its mass to resist change from the hot sun on the outside of a building. Due to its high mass, rammed earth is slow to heat, but with a sufficient amount of sun, that heat would be transferred to the inside of your home and would remain in your wall long after the weather has cooled down.

Insulated thermal mass wall

Another sustainable way to ensure home passive cooling is a high thermal mass wall that is insulated on the outside. This allows you to prevent the outside of your home from heating up or cooling, meaning you benefit from the walls’ ambient coolness in summer and retain heat from your internal heating in winter. 

Insulated concrete forms

In our award-winning Machu Picchu home design, our passive heating and cooling home design solution used a product called Formcraft ICF, otherwise known as insulated concrete forms. Insulated concrete forms cover the outside and inside of the high thermal mass concrete external walls. It is a cost effective and efficient way to ensure a passively cooled house and will benefit your home for the years to come.

Positioning of trees and shrubs

In addition to using passive heating and cooling materials and insulating the walls of your home, you can also strategically position trees, plants and vines to assist in home passive cooling.  Oftentimes, the same positive results can be achieved by the positioning of trees in a way that shades your home or growing a vine over a west-facing wall.

Passive home cooling and heating experts

At Calm Living Homes, we design unique homes that maximise the financial and environmental benefits of passive cooling. Green house design is one of the best ways to create a more environmentally friendly home. We will work with you from the beginning to ensure that your home meets the needs of you, your family and the environment.

We can also apply these sustainable design principles to existing homes, renovating your house so that it will not only look beautiful but also reduce your carbon footprint and save on energy costs. To ensure you have the best passive heating and cooling home design possible, get in touch with the Calm Living Homes team today on 0418 177 380 or fill out our online contact form and we will get back to you.

For further information call Anton Engelmayer on 0418 177 380 or email at [email protected]


The Karate Kid and beautiful long lasting weatherboards

Have you ever wondered about that fantastic dark yet interesting finish that you see on Japanese wooden buildings? If you haven’t then you might recognize it from the picture below. While it looks like a stain it is actually much better than this. Who would not want a beautiful long lasting weatherboard finish that requires no painting and can last for up to 80 years?

The Japanese call them Sugi boards. These are made by burning off the outside layer of cedar weatherboards and then brushing and washing off the burnt carbon. The result is that the remaining top layer of wood becomes harder and resistant to water as well as taking on a beautiful dark brown patina with highlighted grain. While conventional weatherboards need to be regularly cleaned and painted along with wooden shingles Sugi boards are one of the ultimate low maintenance building claddings.

Traditional Japanese builders also used the Sugi technique to create beautiful and long lasting floorboards. We have recently applied this to a radiata pine floor in a home in Berwick and the result, as you can see below, was sensational. Not only does it look beautiful but it is a healthy low environmental impact finish that completely eliminates the work of sanding and the application of toxic finishes such as two pack that emit VOC’s (Volatile Organic Compounds) which can cause a range of health problems.

Call Anton Engelmayer on or email at [email protected]

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