Achieving Energy Efficiency – Case Study – Sunshine Coast Granny Flat Part 2


Welcome back to part 2 of our series where we analyse the energy efficient design of our Sunshine Coast granny flat. Here in the 21st century, an energy efficient design has become imperative as it allows you to design for the future, not just the present. A smart and sustainable building will stand in place for a long time. Good energy efficient building design will decrease your overall power consumption, save you money and help to reduce or limit the effects of climate change. In this series we will explore the design features, local climate and build site of our very own Sunshine Coast granny flat display.

Searching for energy efficient design ideas? Enquire with the Sunshine Coast building experts.

The Design Features

This unique, energy efficient design features many aesthetic and environmental design inclusions. The 90m² internal footprint and 45m² deck is all built upon a suspended steel floor system, with minimal intrusion to the earth below.

The cladding comprises of Australian made, durable & long lasting Colorbond Monument cladding laid horizontally and Hardiflex cladding with responsibly sourced timber battens.

The overall granny flat design was intended to be open plan. Featuring 4m high raked ceilings. The living space makes the most of indoor/outdoor living via large glass sliding doors, enabling the deck to simply be an extension of the living space. High positioned louvres also enable year round cross flow ventilation and passive cooling during the warmer months.

All cabinetry was designed with longevity and sustainability in mind. The locally manufactured kitchen, laundry and bathroom cabinets comprise of soft close hinges and European appliances.

The two large bedrooms also feature large windows allowing ample natural light to flood the space, they also have included separate built in robes maximising storage space cababilities.

All rainwater is collected and stored within the 22,000l poly rain water tank and waste water is also treated on site.

The Build Site, Site Orientation & Local Climate

The aptly named rainforest retreat has been built on a semi-rural parcel of land in Ilkley. The build location was chosen for several reasons. The site is rurally zoned and is located centrally in the Sunshine Coast region. In order to achieve an off grid style build, with maximum energy efficiency ratings, a rural locality was essential. The main demographic of our clientele will find similarities given the locality as well. The build location is a year round warm-temperate climate, reaching averages of 29° in the Summer months dropping to averages of 20° overnight and 21° in the winter months dropping to 10° overnight. The summer months may feel hotter due to the humidity component however, on Sunshine Coast we average an approximate 60% humidity level in the Summer months. Those familiar with humidity will understand the need for reprieve during the warmer months. In addition, as this is considered a warmer climate, drops in the temperature can be noticed quite dramatically.

Many different options were discussed when planning the orientation and placement of this granny flat. In the end, a North-East orientation was chosen, conductive to good energy efficient design principles. The overall floor print is staggered (think two rectangles joined together) to maximise the ventilation and natural light. 

Ilkley Rainforest Retreat - Outdoor Area

Understanding the energy efficient design principles is very important to us all here at The Shed House. As we are passionate about this world we all live in. Stay tuned for part 3 in the 4 part series where we explore this Sunshine Coast granny flat design. Next, we will discuss and analyse the design response – after careful analysis of the site how we successfully achieved an energy efficient granny flat build.

Contact us for more energy efficient design ideas. Trust your local Sunshine Coast builder.