Question:   How many stars does a new house require?

  1. 5 stars
  2. 6 stars
  3. 10 stars
  4. No stars

Answer:   4. No stars, (although there is a bit more to it).

The actual requirement is that the house needs to be compliant as per the NCC (National Construction Code) in accordance with the Performance Requirements.

There are a few ways to do this:

  1.  Conduct a Thermal Performance Assessment using approved simulation software (where the result must be minimum 6 stars).
  2. Use the NCC Deemed to Satisfy method. This prescriptive method involves specifying thermal requirements as prescribed in the Code.
  3. Proposing an Performance Solution that satisfies the NCC Performance Requirements.
  4. A combination of the afore mentioned methods.

As you can see, the original question is actually a slightly misguided one. Most people relate new houses to ‘star levels’ but this is not the actual requirement.

So, what is the best approach?

The best approach is to choose the method best suited to the individual circumstance. This can vary from job to job.

One important thing to note is that a Thermal Performance Assessment, (star rating) only assesses the thermal fabric of the building in relation to heating and cooling loads. It does not assess:

  • lighting
  • services
  • hot water systems
  • condensation

As part of our energy compliance reports we  make sure to address all components. Our approach is to not look at  thermal performance in isolation but to address it as part of a holistic system of achieving a comfortable,  energy efficient and healthy home.