Window considerations for a high-performance home
Image above shows CBG Quality Builders Wanaka Showhome - which received a blower door test result of 0.18 air changes per hour @ 50Pascals. Standard construction is 5 - 7 air changes per hour @ 50Pascals.
When building an energy-efficient home in New Zealand, one of the key considerations should be the type of windows you use. High-performance windows can play a significant role in reducing the amount of energy needed to heat and cool your home, ultimately saving you money on energy bills in the long run.
There are several characteristics to look for in high-performance windows that can help make your home more energy-efficient. In New Zealand, a desirable R-value for windows is between R0.65 and R0.8, which can be achieved with uPVC or timber windows with Low-E double glazing, or thermally broken aluminium windows with Low-E double or triple glazing. Prior to November 2022, the NZ Building Code required a minimum of R0.26 with cold aluminium frames and clear double glazing, but this is no longer sufficient. To determine the R-value of your windows, consider the R value of both the frame and the glass. You can ask your builder or window company to specify these values, as they affect energy transfer through the window. It is important to consult with your builder or window company to get the best outcome, as their default option may not be optimal for you.
High-performance windows should also be well-sealed to prevent drafts. This can help prevent air leakage, which can also contribute to heat loss. This is where the installer must consider air leakage when installing windows on your home.
In summary, when building an energy-efficient home in New Zealand, it is important to consider the type of windows you use. High-performance windows with high R-values, window type (extra glazing or thermally broken), and well-sealed windows can all play a significant role in reducing the amount of energy needed to heat and cool your home. This will ultimately help you save money on energy bills in the long run.
You can learn more about high-performance windows from some of our recommended high-performance window supplier experts listed below.
Large window suppliers such as Fairview, Vantage, and Altus (to name only a few) also offer high-performance window ranges.