Solar-Powered Granny Flats: Welcome to the Future

granny flats

granny flatsOne of the most popular secondary accommodations in Australian homes, granny flats – also known as a secondary suite, granny suite, or in-law suite – is a part of a property converted into a self-contained accommodation. It is one of the most useful means of adding value and flexibility to your current home setup.

One of the new schemes in granny flats is a passive solar design, which helps mitigate utility costs as well as being beneficial to the environment.

Features of Passive Solar Design

Most people associate “solar design” on homes as those with solar cells on the roof or on the lawn to collect solar energy. This is not the case for passive solar homes, which rejects heat during summer while distributing that heat during winter, precluding the need for additional utilities.

Architects design this not through a total remodel of the flat, but simply by integrating special materials on the walls, windows and floors, and constructing the home in a way to take advantage of natural processes. The great thing about the design is that there is no need for any mechanical and electrical devices.

Window Location

The location of windows is crucial to the implementation of passive solar design. For example, larger windows should be on the north side so that sunlight during winters can penetrate the interior and warm the space naturally. To the east and west, smaller windows lessen the harsh summer sun during the mornings and afternoons. Proper lighting and ventilation can come from windows installed on the south end.

Flooring Option

To ensure proper breeze pathways, ensure that flooring options do not restrict the passage of cool air to the home. recommends that the flooring be as even as possible, and to use wood instead of other materials.


Special materials insulate the floors and walls to distribute and circulate heat. This happens through the process of conduction, convection and radiation.

Using passive solar design in granny flats can reduce utility bills in the long run. Consult experts in the field so they can advise you on incorporating these designs in your secondary suite.

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