Auckland · Free, client-side, no email
Three calculators that show their working.
Most renovation calculators are lead forms. You put in a floor area, they put out a confident number from a source they will not name, and then they ask for your phone number. These three do the opposite: every one runs in your browser, asks for nothing, and prints the arithmetic underneath the answer so you can check it — and disagree with it.
13
building trades with real published hourly pay bands behind the budget calculator, from the Tertiary Education Commission. Not a per-square-metre guess — a labour component built from wage data, with the assumptions on the page.
Tertiary Education Commission — Tahatū Career Navigator · retrieved 2026-07-30
Photography commissioned — plate reserved · July 2026
The three
What each one is for.
Renovation budget
Pick your scope, and the calculator builds a labour component from real trade pay rates, adds your materials allowance, a contingency you set, and consent and professional fees as separate lines.
Consent likelihood checker
Fourteen job types against the published rules. Outputs likely, conditionally exempt, or ask Council — never a definitive yes or no, because only Council can give you one.
Renovation return & payback
Real median weekly rents for 246 Auckland suburbs from MBIE bond data. Model a spend against a rent change, and see the gross yield shift and the payback period.
The rule these follow
A number without a method is decoration.
New Zealand publishes no free, official figure for what it costs to paint or renovate a house. Stats NZ publishes the declared value of building consents, which is the applicant’s own estimate, excludes land, and is inconsistent on GST. It publishes cost indexes, which track movement rather than level. And it publishes construction wages. None of them is a price for a job. The only commercial cost libraries — QV CostBuilder and the former Rawlinsons handbook — are paid, licensed products we are not permitted to republish. So where this site shows a range, it says exactly where the range came from, and where it can only show surrounding market context, it says that too.
So each calculator separates three kinds of input and labels them, because they carry completely different weight:
- Published data. Trade pay bands from the Tertiary Education Commission. Median weekly rents from MBIE's rental bond data. Both dated, both linked to source.
- Judgement. How many labour hours a bathroom refit takes. What multiple turns a wage into a charge-out rate. Both are stated as judgement, both are printed in the working, and both are inputs you can change.
- Yours. Materials allowance, consent and professional fees, expected rent, property value. The calculator will not invent these, because they are the numbers you can actually find out.
The one thing none of them will do is give you a per-square-metre renovation rate, because no free official New Zealand source publishes one. The long version of why.
Questions people actually ask
Do I have to give you an email address to use these?
No. There is no gate, no sign-up and no "unlock your result". Every calculator on this site runs in your browser the moment the page loads, and nothing you type is sent anywhere. That is a deliberate choice: a calculator that harvests an address before it answers is a lead form wearing a costume.
Are these calculators quotes?
No, and the pages say so in the first screen. They are planning estimates built from published data plus stated assumptions, and each one shows the arithmetic so you can check it and change the assumptions you disagree with. A quote comes from someone who has stood in your house.
Where do the numbers come from?
The budget calculator uses real hourly pay bands for thirteen building trades published by the Tertiary Education Commission, plus a labour-hours allowance this site states as its own judgement. The return calculator uses MBIE rental bond medians for each of the 246 Auckland suburbs on this site. The consent checker uses the published rules — the Building Act's Schedule 1 and the Auckland Unitary Plan — and outputs likelihoods, never determinations.
Why does the budget calculator not just ask for my floor area?
Because a per-square-metre figure for renovation work does not exist in any official New Zealand source, and it is a poor predictor anyway. A 20 m² bathroom and a 20 m² bedroom are not the same job. Building the number up from scope items and trade hours is more work for you and much closer to how a real quote is assembled.
Will these calculators work on my phone?
Yes. They are plain HTML inputs with a small script, they reflow to one column on a narrow screen, and they work with a keyboard and with a screen reader. If JavaScript is off, each page explains what is missing and points you to the page that covers the same ground in prose.
Painting calculators
Paint quantity, surface area and a landlord repaint return — same rules, same no-email policy.
Paintwork Auckland