A number needs context. We show the assumptions so you can judge whether an estimate fits your home.
Sources for New Zealand
Our heat pump tool links to EECA for grant information, MBIE for building and heating guidance, and a dated installation pricebook for published price ranges. A source link is not an endorsement of our model by that organisation.
How the heat pump estimate works
The sizing estimate uses room volume with adjustments for insulation, climate, building age, exposure, glazing and target temperature. Optional room detail supports different insulation and glazing assumptions. This is a simplified heat-loss proxy, not a full engineering calculation.
The installed budget uses broad published system price ranges and scenario adjustments. Running costs combine the estimated capacity, operating hours, heating days, electricity rate and an assumed efficiency. Actual operating behaviour and equipment performance can differ substantially.
Current validation status
The heat pump model is in planning beta. Internal desk checks are documented, but they do not establish independent professional approval. External HVAC review and validation against a wider set of real installation quotes remain outstanding.
Dates and updates
The calculator and pricebook show their review dates. That date identifies the version reviewed; it does not mean every source is live or that prices will remain unchanged. Confirm time-sensitive prices, funding and rules before committing to work.
Automation and judgement
AI-assisted development has been used to build this site and prepare material. That is not a substitute for primary sources, calculation checks or professional advice. We do not present AI output as a professional certification.
Corrections
If a result or source appears wrong, send the page address, inputs and supporting information. Material model changes should be reflected in the displayed assumptions, review date and project change record.
Funding and advertising
The current site has no display ads or affiliate tracking links installed by us. If advertising or paid relationships are introduced, we will identify sponsored material and update the relevant disclosures. A commercial relationship should not determine a calculation result.