Reviewed 28 August 2026 · New Zealand homeowner guidance
There is no reliable single price for a renovation. A useful budget starts with the work being changed, the condition behind existing finishes and how completely the project has been specified.
Start with a planning range, not a promise
Published New Zealand guides put professional kitchen renovations broadly around $25,000 to $75,000, bathrooms around $20,000 to $65,000, and substantial whole-home work from roughly $100,000 upward. These are orientation ranges, not quotes. Layout changes, structural work, access, age, specification and location can move a real project well outside them.
The useful question is not simply ‘What does a renovation cost?’ It is ‘What scope could be delivered at this property, to this finish, with this level of uncertainty?’ A builder can price that question far more reliably.
The five parts of a renovation budget
Separate the budget into construction, professional services, statutory costs, owner-supplied items and contingency. If everything sits in one number, it is easy to spend the contingency on appliances or design fees before construction starts.
- Construction: labour, materials, subcontractors, site setup and project management.
- Professional services: design, engineering, surveying or specialist reports where required.
- Statutory costs: building consent, inspections and other council charges that apply to the scope.
- Owner selections: appliances, tapware, lighting, flooring and other items bought directly.
- Contingency: money held for genuine uncertainty, not upgrades already being considered.
Why two similar homes can price differently
Renovation pricing is affected by what cannot be seen during the first visit. Older wiring, plumbing, framing, moisture damage, asbestos-containing material, uneven floors and undocumented alterations may only become clear after opening up.
Access also matters. Carrying materials through an occupied house, protecting retained finishes, working on a steep section or staging work around the family all add time without adding visible square metres.
Allowances can hide the real comparison
A prime cost sum is an allowance for an item not finally selected. A provisional sum is an allowance for work whose extent is not yet known. Neither is automatically a problem, but a quote with low allowances can look cheaper than one based on realistic selections.
Ask what quantity, quality and installation cost each allowance assumes. Wherever possible, make key selections and investigate uncertain work before asking builders for final prices.
A budget becomes useful when the brief becomes specific
Record the rooms, layout changes, retained elements, finish level, site constraints and intended timing. Identify decisions that are fixed and those still open. This gives each builder the same starting point and makes later quote comparison more meaningful.
The next useful step is to build a project brief, not chase a precise online number. A planning range helps you decide whether to continue; drawings, selections and site investigation are what make a price dependable.
Frequently asked questions
How much contingency should I allow?
Consumer Protection suggests allowing roughly 10–15% for surprises. The right amount depends on how much is known, the age of the house and whether walls, services or structure will be opened.
Is a renovation quote the final price?
An accepted quote is generally expected to hold unless you agree to extra work or the scope changes. Read the contract, exclusions, allowances and variation process together rather than relying on the total alone.
Should I tell builders my budget?
Yes, if you frame it clearly. State the total funds available and what must fit inside them, including design, consent, owner purchases and contingency. This prevents a construction quote from consuming money reserved for other costs.
When should I ask for a fixed price?
Ask once the scope, drawings and major selections are sufficiently resolved. Seeking a fixed price too early usually creates exclusions and allowances rather than genuine certainty.
Sources and further reading
Turn the decisions into one renovation brief
Once the broad scope, location, budget and timing are clear, record them together before approaching builders.
Prepare a project brief