Insulation and Glazing Calculator

How much money on heating costs can insulation, double glazing or air tightening save me?

We are consistently told by manufacturers that we could save loads of money double glazing or insulating our homes. But how much? This is what we are trying to help you find out for your circumstances here with our calculator. The first calculator is NZ specific with NZ weather and insulation data. The second calculator can be used from anywhere in the world.

Here how it works:

  1. Fill in the green fields for your current situation in your home. Note the kWh end result is for the size of heating system that you currently require.

  2. Change the field to what you want to upgrade to: for example, if you are looking at upgrading your windows, change the option of glazing to what you are after. Again, note down the kWh end result is for the size heating system that you would require after the upgrade.

  3. The difference is your estimated saving. For example, if with double glazing you only require a heating system that is 2/3 of the size than with single glazing, then you will save about 1/3 off your heating costs. The calculation is of course based on that you will keep the house at the same temperatures and the weather will stay the same as in the past years.

Different climates, materials and living stiles require different products for best results. Get in touch for a free consultation- we help you find what works best for you according to science, not a marketing message.

Please be aware that this is just a guide, the data behind it is based on publicly available data. The requirements for your specific homes might vary. For the NZ calculator we have assumed a 2.4 m ceiling height and 30% of external walls to be glazed.


Contact us:

Christchurch, New Zealand