Red Flags When Choosing a Builder in NZ

The warning signs that should make you walk away from a builder, and the ones to address in writing - from first contact through quotes, contracts and construction.

By Bracen

A quick reference guide for vetting builders before and during your home build.

Red Flags During Initial Contact

Walk away if:

  • No LBP number or insurance - restricted building work must be carried out or supervised by a Licensed Building Practitioner, and a legitimate builder can show you their LBP number and insurance on the spot
  • Cash-only deals - legitimate builders issue GST invoices and accept bank transfer
  • Pressure to sign immediately - "this price expires today" is a manipulation tactic
  • Vague or evasive answers - they can't explain their process or timeline clearly
  • No references - they won't provide past client contacts or addresses of completed jobs

Caution if:

  • They push to start before the building consent is issued
  • Communication is inconsistent (days to respond to basic questions)
  • They bad-mouth every other builder in town
  • Everything is verbal - no written estimate

Red Flags in Quotes and Proposals

Walk away if:

  • Suspiciously low quote - 20%+ below other quotes usually means shortcuts now or variations later
  • Verbal-only quotes - no itemised breakdown in writing
  • Provisional sums for everything - vague placeholders instead of actual material costs
  • Major items missing - no line for consent fees, site prep, or cleanup

Caution if:

  • The quote says "materials to be confirmed" with no clear selections process
  • The payment schedule is front-loaded (50%+ before work starts)
  • No defects liability period or guarantee is mentioned
  • The timeline is unrealistic (a custom home in 8 weeks)
  • The variation process isn't explained upfront

Red Flags in Contracts

Walk away if:

  • No written contract - for residential building work over $30,000 a written contract is required by law, and a builder who resists one is telling you something
  • The contract heavily favours the builder - all the risk sits with you, none with them
  • No detailed scope of work - it just says "build house as discussed"
  • No mention of how subcontractors are engaged and paid - unpaid subbies become your problem mid-build
  • No termination clause - you're locked in with no exit

Caution if:

  • Payment milestones aren't tied to completed work stages
  • No start date or completion date is specified
  • The builder requires final payment before the final walkthrough
  • The contract includes a blanket waiver of your rights (the Building Act's implied warranties apply to residential work regardless of what the contract says)
  • Variation markup isn't specified (some charge 20-40%)
  • No third-party guarantee is offered, and they dodge the question when you ask what happens if they go under

Red Flags During Construction

Walk away if:

  • Restricted work isn't being done or supervised by an LBP - ask who is signing the records of work
  • Work doesn't match the consented plans - unapproved departures can void your consent and stall your Code Compliance Certificate
  • Payment requested ahead of schedule - especially before the work it covers is complete
  • Avoiding council inspections - legitimate builders welcome them
  • Materials disappearing - your materials turn up on another job

Caution if:

  • The crew changes constantly (high turnover means management issues)
  • The builder is unreachable for days when issues come up
  • They rush you into selections without explanation
  • Every delay is blamed on others (subbies, suppliers, weather) with no recovery plan
  • The site is consistently messy or unsafe
  • Work quality is inconsistent between areas

When to Walk Away vs When to Address It

Walk away immediately:

  1. No LBP involvement or insurance
  2. Pressure tactics or manipulation
  3. Unwilling to provide a written contract
  4. Asking for full payment upfront
  5. Work being done without a building consent
  6. The builder becomes hostile when you ask reasonable questions

Address and document:

  1. Minor communication issues - set expectations in writing (weekly updates, response times)
  2. Unclear timeline - request a detailed schedule with milestones
  3. Material substitutions - require written approval for any change
  4. Small quality concerns - document with photos, request fixes before the next payment
  5. Slow progress - ask for a recovery plan in writing

The key principle: trust your gut. If something feels off, pause and get a second opinion. Changing builders mid-project is expensive, but finishing with the wrong builder is worse.

Your Action Checklist

Before signing with any builder:

  • Verify their LBP number on the public LBP register, and ask for proof of insurance
  • Search the company on the Companies Register and read recent reviews
  • Visit at least 2 active job sites
  • Speak to 3 or more past clients (ask specifically about communication and variations)
  • Get 3 written quotes for comparison
  • Have a lawyer review the contract - it costs a few hundred dollars and can save you tens of thousands
  • Confirm who lodges the building consent and manages inspections
  • Understand the payment schedule, and keep the deposit at 10% or less
  • Ask how subcontractors are paid and whether retentions are held
  • Document everything in writing - texts and emails count

A good builder will welcome your questions and due diligence. A bad one will resist it. Your build is likely the largest investment you'll ever make - protect it.

For the full step-by-step process, read The NZ Home Build Blueprint.

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