Getting a written quote from a deck builder is one of the most important steps in any outdoor project. A detailed, clear quote protects both you and the tradesperson — and makes it much easier to compare builders fairly. Here's what to look for before you sign on the dotted line.
Scope of Work: What Exactly Is Included?
The quote should spell out exactly what work will be done, from start to finish. Vague quotes lead to disputes. Look for:
- Site preparation (clearing, levelling, removal of existing structures)
- Subframe and bearer/joist specifications
- Decking board species, grade, and finish
- Fixings, fasteners, and hardware types
- Balustrades, stairs, and handrails (if applicable)
- Any waterproofing or drainage provisions
- Rubbish removal and site clean-up
If something isn't listed, assume it's not included — and ask.
Materials: Brand, Grade, and Treatment
A good quote names the specific materials to be used, not just generic descriptions like "treated timber." In New Zealand, timber used in outdoor decking must meet the requirements of NZS 3604 and be appropriately treated for its hazard class (H3.2 minimum for above-ground exterior use, H4 or H5 where in contact with the ground or water).
Look for:
- Timber species (e.g., pine, kwila, cedar, composite)
- Hazard class and treatment standard
- Decking board dimensions (thickness and width)
- Brand or supplier of composite or hardwood products
If the builder is using composite decking, ask for the product datasheet. Reputable suppliers like those stocked at Mitre 10 or PlaceMakers will have full technical specifications available.
Building Consent: Who's Responsible?
This is critical. In New Zealand, decks over 1.5 metres above ground level generally require a building consent from your local council. Some lower decks may qualify as exempt work under Schedule 1 of the Building Act — but you should always confirm this with your council before work begins, as rules vary by location and deck design.
The quote should clearly state:
- Whether a building consent is required
- Who will apply for and manage the consent process
- Whether consent fees are included in the quoted price
For guidance on consent requirements, MBIE Building Performance is the authoritative source. A builder who dismisses consent requirements without checking is a red flag.
Pricing: Fixed Price vs. Estimate
Understand whether you're receiving a fixed-price quote or a cost estimate. These are very different things:
| Type | What it means |
|---|---|
| Fixed price | You pay the stated amount (barring agreed variations) |
| Estimate/budget | Final cost may change based on actual time and materials |
| Day rate | Charged per hour or day — final cost is open-ended |
For most residential deck builds, a fixed-price quote is preferable. Make sure GST is clearly included or excluded, and that any provisional sums (allowances for unknown costs) are clearly identified.
Payment Terms and Schedule
A professional quote will outline a payment schedule tied to project milestones — not just a lump sum upfront. Be cautious of any builder asking for more than a reasonable deposit (typically 10–20%) before work starts. Look for staged payments linked to:
- Completion of subframe/foundations
- Completion of decking boards
- Practical completion and sign-off
Timeframes and Start Date
The quote should include an estimated start date and a realistic timeframe for completion. Weather delays are common in New Zealand, so ask how these are handled. A clear programme helps you plan and holds the builder accountable.
Warranties and Guarantees
Ask what warranties are offered on both workmanship and materials. Under the Building Act, builders have obligations around defective work, and the Consumer Guarantees Act also provides protections. Some builders offer additional written guarantees — this is a positive sign. Check whether the builder is a Licensed Building Practitioner (LBP), as restricted building work on certain decks must be carried out or supervised by an LBP.
Insurance and Licensing
Before accepting any quote, confirm the builder holds:
- Public liability insurance (ask for a certificate)
- LBP licence if the work is restricted building work
- Any relevant trade memberships
WorkSafe NZ sets health and safety obligations for construction sites — a professional builder will have a site safety plan.
Variations: How Are Changes Handled?
The quote should explain the process for variations — changes to the original scope. Any variation should be agreed in writing before additional work proceeds, with a clear price attached. Verbal agreements about changes are a common source of disputes.
When to Call a Professional
Deck building that involves restricted building work — including certain structural elements and anything requiring a building consent — must be carried out or supervised by a licensed tradesperson. If you're unsure whether your project qualifies, check with your local council or visit MBIE Building Performance. You can find qualified, local deck builders on tradedirectory.co.nz.
Always get at least three written quotes and compare them line by line. The cheapest quote isn't always the best value — look for detail, transparency, and professionalism.
Licensed Building Practitioner (LBP)
