Getting a concreting job done right starts well before the first truck arrives — it starts with a thorough, written quote. A good quote isn't just a price; it's a clear record of what you're both agreeing to, and it can save you from costly disputes down the track.
A Written Quote Is Non-Negotiable
Always insist on a written quote, not just a verbal estimate. A written document protects both you and the contractor. It should be signed and dated, and you should receive a copy before any work begins. Verbal agreements are notoriously hard to enforce if something goes wrong.
Scope of Work
The quote should clearly describe exactly what work is included. For a concrete job, this typically means:
- Area to be concreted (in square metres)
- Thickness of the slab (in millimetres — e.g. 100 mm for a standard driveway)
- Purpose of the concrete (driveway, path, patio, shed floor, etc.)
- Any formwork (boxing) required
- Subbase preparation — will the contractor excavate, compact, and lay a gravel subbase?
- Reinforcing steel (mesh or rebar) — type, size, and placement
- Whether control joints (crack-control cuts) are included
- Surface finish — broom finish, exposed aggregate, pattern imprint, or plain
- Curing method and any sealer application
If any of these items are missing, ask the contractor to add them before you sign.
Concrete Specification
This is one of the most important — and most commonly overlooked — parts of a quote. The quote should state the concrete mix design, including:
- Compressive strength (e.g. 25 MPa or 30 MPa — higher is stronger)
- Aggregate size (typically 20 mm for most residential work)
- Slump (workability of the mix, usually 80–100 mm for driveways)
- Whether the concrete is ready-mix (from a batching plant) or site-mixed
For most residential driveways and paths, a minimum of 25 MPa is standard practice in New Zealand. If you're in a coastal or frost-prone area, a higher-strength mix or air-entrained concrete may be recommended — check with your contractor and, if in doubt, consult BRANZ for guidance on appropriate specifications.
Site Preparation and Conditions
The quote should spell out who is responsible for:
- Clearing the area (removing existing concrete, pavers, or vegetation)
- Excavation depth and disposal of spoil
- Compaction of the subbase
- Access for the concrete truck and pump (if required)
- Any tree root or drainage issues that may affect the job
If site conditions are unusual — for example, poor ground, a steep slope, or limited truck access — the quote should acknowledge this and explain how it will be handled.
Pricing Breakdown
A transparent quote will show you how the price is made up, not just a single lump sum. Look for:
| Item | What to check |
|---|---|
| Labour | Number of workers, estimated days on site |
| Materials | Concrete volume (m³), reinforcing, formwork |
| Plant hire | Pump, compactor, screed rails |
| Disposal | Spoil removal, skip bin |
| GST | Confirm whether the price is GST-inclusive or exclusive |
As a rough guide, residential concreting in NZ can range broadly depending on region, finish, and complexity — always get at least two or three quotes to compare.
Building Consent and Compliance
Some concreting work requires a building consent from your local council. This is particularly relevant for:
- Concrete slabs that form part of a habitable building
- Retaining walls over certain heights
- Work that affects stormwater drainage
Simpler work like a driveway or garden path may be exempt under Schedule 1 of the Building Act 2004, but this varies by council and project. Always confirm with your local council before work starts — don't rely solely on the contractor's advice. You can find general guidance at MBIE Building Performance.
The quote should state clearly who is responsible for obtaining any required consents and whether consent fees are included in the price.
Payment Terms and Schedule
Before signing, make sure you understand:
- Deposit amount (a reasonable deposit is normal, but be cautious of requests for more than 20–30% upfront)
- Progress payments (if any, and what triggers them)
- Final payment timing — typically on completion and your sign-off
- Accepted payment methods
Never pay the full amount before the job is finished and you're satisfied with the result.
Variations and Extras
The quote should explain the process for variations — changes to the scope of work that arise during the job. Ideally, any variation should be agreed in writing before the extra work is carried out, with a clear price attached.
Warranties and Guarantees
Ask whether the contractor offers any workmanship warranty. While concrete is a durable material, poor placement, inadequate curing, or insufficient reinforcing can lead to cracking or surface defects. A reputable contractor should stand behind their work.
Note that your rights under the Consumer Guarantees Act apply regardless of what the quote says — services must be carried out with reasonable care and skill.
When to Call a Professional
Concreting is not a licensed trade in the same way as electrical or plumbing work, but it is a skilled trade that requires experience to get right. Poor concrete work is expensive to fix. For anything beyond a very small DIY project, it pays to hire a qualified concreter.
If your project involves drainage connections or changes to stormwater, a licensed drainlayer may also be required — check with the Plumbers Gasfitters & Drainlayers Board. For any structural concrete work, consult a Licensed Building Practitioner.
You can find experienced, local concreters on tradedirectory.co.nz.
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