Technically, a roofer can start work without giving you a written contract — there's no single NZ law that flatly prohibits it. However, doing so leaves both you and the tradesperson exposed to serious disputes over scope, price, and liability. A written contract is your best protection, and any reputable roofer should provide one before a single tile is lifted.
What the Law Actually Says
New Zealand doesn't have one specific "roofing contracts" act, but several pieces of legislation are relevant:
- The Contract and Commercial Law Act 2017 recognises verbal contracts as legally binding, but proving what was agreed becomes very difficult without written evidence.
- The Consumer Guarantees Act 1993 gives you rights to services carried out with reasonable care and skill, completed within a reasonable time, and fit for purpose — regardless of whether you have a written contract.
- The Fair Trading Act 1986 protects you from misleading conduct, including vague or deceptive quotes.
For larger residential building projects, MBIE Building Performance provides guidance on residential building contracts. Under the Construction Contracts Act 2002, any construction contract (including roofing) worth more than $30,000 (including GST) must be in writing. Below that threshold it's strongly recommended but not legally required.
Why a Written Contract Matters for Roofing Work
Roofing is one of the higher-risk trades in terms of cost blowouts and disputes. A written contract should clearly set out:
- Scope of work — exactly what is being replaced, repaired, or installed (e.g. full re-roof, ridge capping, flashing, gutters)
- Materials specified — brand, profile, colour, and gauge of roofing iron or tiles
- Price and payment schedule — deposit amount, progress payments, and final payment terms
- Timeline — start date, estimated completion, and what happens if weather causes delays
- Warranties — both the manufacturer's product warranty and the tradesperson's workmanship warranty
- Variations process — how changes to scope are agreed and priced
- Dispute resolution — what happens if something goes wrong
Without these details in writing, you have very little leverage if the roofer uses cheaper materials than quoted, the job drags on for months, or the finished work leaks.
Building Consents and the NZ Building Code
Depending on the scope of work, a building consent may be required. A straightforward like-for-like re-roof on a residential dwelling is often exempt under Schedule 1 of the Building Act 2004, but this depends on the specific situation — always confirm with your local council before work starts.
Where a consent is required, the work must comply with the NZ Building Code, particularly Clause E2 (External Moisture), which governs weathertightness. Your roofer should be familiar with these requirements. If the work requires a consent, the contract should reference this and clarify who is responsible for obtaining it.
For larger or more complex roofing projects, the roofer may need to be a Licensed Building Practitioner (LBP) to carry out or supervise restricted building work. Always ask to see their LBP licence number and check it on the LBP register.
Red Flags to Watch For
Be cautious if a roofer:
- Asks for a large upfront deposit (more than 10–20% is unusual for most jobs)
- Refuses to provide anything in writing
- Can't give you a clear itemised quote
- Pressures you to sign or start immediately
- Has no verifiable business address or registration
Consumer NZ has useful guidance on hiring tradespeople and your rights when things go wrong.
What a Good Quote Should Include
Before any contract is signed, you should receive a detailed written quote. Use this table as a checklist:
| Item | What to Look For |
|---|---|
| Scope of work | Specific, not vague |
| Materials | Brand, spec, colour confirmed |
| Price | GST-inclusive total |
| Payment terms | Staged, not all upfront |
| Timeline | Start and finish dates |
| Warranties | Workmanship and product |
| LBP number | If restricted work is involved |
When to Call a Professional
All significant roofing work — re-roofing, structural repairs, flashing replacement, or anything requiring a building consent — should be carried out by a qualified, experienced roofer. If the work is restricted building work under the Building Act, it must be done or supervised by an LBP.
Never let anyone start work on your roof without a written agreement in place. If a tradesperson won't provide one, that's a strong signal to look elsewhere. You can find reputable local roofers on tradedirectory.co.nz.
Safety note: Roofing work involves working at height, which carries serious fall risks. Ensure your roofer has a site-specific safety plan and appropriate equipment. WorkSafe NZ sets out the legal requirements for working at height.
Roofing Association of NZ (RANZ)
Licensed Building Practitioner (LBP)
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