Energy Efficiency

A great way to measure energy efficiency is by understanding how many air changes per hour your home might have. The more air changes, the more energy required and the higher the cost to heat your home.

This graph shows you that even new houses built to today’s code minimum standards have extensive air changes – in some cases the equivalent of leaving a 1m2 window open all the time.

Costs to Build – Housing Quality vs Price


How big a house do you need (if it’s designed to use space efficiently)?

  • 2 Bed / 1 Bath / Garage – 120m²
  • 3 Bed / 2 Bath / Study / Garage – 160m²
  • 4 Bed / 2 Bath / Study /2nd living / Garage- 195m²

Figures refer to the area of the house, including a double garage, but not including; Decks, Alfresco areas, Landscaping.
Building contract price is as signed with a builder based on Canterbury, NZ building costs. Download a copy of this resource.