The Passive House concept was first developed by German physicist Dr. Wolfgang Feist during the early 1990s in Darmstadt, Germany. The goal was to create buildings that use very little energy for heating and cooling, while still providing a high level of comfort for the occupants.

The exact definition of Passive House, as provided by the Passivhaus Institut is as follows:

“A Passive House is a building, for which thermal comfort (ISO 7730) can be achieved solely by post-heating or post-cooling of the fresh air mass, which is required to achieve sufficient indoor air quality conditions – without the need for additional recirculation of air”

Dr. Wolfgang Feist (via Passive House Institut)

The National Construction Code (NCC formally known as the BCA) will soon require all new residential dwellings in Australia (Except NSW)* to achieve a minimum of a 7 Star Rating using the Nationwide House Energy Rating Scheme (NatHERS), approved software.

With climate change being at the forefront of challenges we must begin to address, we have to reconcile with adapting our lives to the state of the world we live in. From buying tote bags and metal straws to reducing meat consumption, much of the actions we are to personally take are often cumbersome. It hurts my soul to limit my steak burrito intake to once a week! Unlike most of these personal adjustments, however, adopting a Passive House Design layout for your home would not only improve your living standards but come with a myriad of benefits for homeowners and landlords alike!

Building for the Australian Climate.

A building’s access to sunlight is one of the leading factors contributing to its thermal comfort, with the amount of direct sunlight that the building receives greatly influencing the passive heating and cooling factors. However, as the sun’s path varies seasonally, accounting for the required direct sunlight a building needs becomes difficult. The eaves of building construction can maintain great benefits if used correctly.

We've found 5 quick and easy tips that will help guide on how to make your decisions in building a sustainable home. 

Building Sustainability Index (BASIX) is a planning tool to assist the NSW State Government ensure that all new developments and alterations are water and energy efficient. The overall goal of BASIX is to contribute to the sustainable future of NSW by reducing water consumption and greenhouse gas emissions by 40% as compared to buildings prior to introduction of BASIX.

Passive cooling is the cheapest method of cooling a home, and as an added bonus is incredibly environmentally friendly. No matter the climate you live in, you'll be using passive cooling to some extent throughout the year.

Whether you live in an apartment or a larger home, your home can be built or modified to allow you to take advantage of passive cooling systems to help you achieve greater comfort. If you already rely on mechanical cooling systems (like air conditioners) you can reduce your energy costs by combining these with passive cooling.

Choosing the most appropriate passive cooling strategies for your home should be guided by the climate you live in. We've listed some of the basic strategies below to get you started!

The BASIX assessment and NatHERS process is an ever evolving practice which requires extensive knowledge of available materials, passive heating and cooling strategies and how to design in an ecologically sustainable manner. Although to complete and sign off on the BASIX process one must be a certified assessor. The assessor’s background does not play a large role in determining their competency in assessing a building’s efficiency. Therefore, the question is raised as to who is the most qualified or most knowledgeable to be completing the BASIX assessment?

You really need to check with the council. 
While not particularly a ‘relocatable home’ as it sounds like an existing residence, not a new prefab one, this is the only information on the BASIX website:

BASIX (Building Sustainability Index) assesses the energy and water efficiency of your development. It is one of the most important planning tools currently operating in NSW to ensure buildings are being developed to operate in a sustainable manner. In NSW the State Government requires that a BASIX Certificate is attached to all development plans when submitted for DA approval.