Concretor on a residential job: scope, licensing, tolerances, working with other trades

TL;DR

The concretor supplies the labour for formwork, reinforcement placement, concrete placement and finishing on residential slabs, footings, paths, and driveways. AS 2870:2011 (Residential slabs and footings) is the design and construction standard for Class 1 and Class 10 residential work, covering site classification, footing types, and concrete grade requirements. Pricing for a house slab package varies widely by region and job complexity; supply boundaries between the concretor’s labour, the concrete truck (batching plant supply), and the engineer’s design are the most common source of variations. The critical hold point for a residential slab is the pre-pour inspection: the certifier or building inspector must sign off formwork and reinforcement before the pour begins. A pour that starts without sign-off is a structural defect and usually requires breaking out and repour.

What this trade covers

The concretor on a residential job is responsible for the concrete work from setting up formwork through to curing. On a standard residential project they typically work across four categories.

Footings and edge beams: setting out and forming up the edge beam, strip footing, or pad footing in accordance with the engineer’s design and AS 2870:2011 site classification. The concretor places reinforcement to the reo schedule and prepares for the pre-pour inspection before placing concrete.

Slab on ground: the most common residential concretor package. Formwork, trench mesh and bar placement to the structural engineer’s details, receiving and placing the concrete truck load, screeding and power-floating or hand-trowelling to finish level, then curing.

Paths, driveways, and aprons: off-slab flatwork around the dwelling. May use plain or reinforced concrete depending on the engineer’s requirements and the soil classification. Finish options include broom finish, exposed aggregate, or standard steel trowel.

Retaining walls and concrete structures: reinforced concrete retaining walls designed to AS 3600:2018 (Concrete structures) for walls outside the geometric limits of AS 2870. Engineer’s details govern reo placement and pour sequence.

What’s in scope (typical residential)

Formwork set-up, including edge forms, kicker boards, and void-former systems (waffle pod or ribbed) to engineer’s design
Reinforcement placement and tie-wire fixing per reo schedule and AS 2870:2011
Bar chairs and spacers to achieve correct concrete cover
Ordering and receiving the concrete truck; coordinating delivery sequence with the batching plant
Concrete placement: chute, pump, or buggy depending on access
Compaction and vibration during placement
Screeding, power-floating or hand-trowelling to specified finish
Curing compound or wet hessian and poly cover for the curing period
Paths, driveways, and aprons as specified

What’s out of scope (often confused)

Structural design: the slab and footing design is engineer scope under AS 2870:2011 and AS 3600:2018. The concretor constructs to the engineer’s drawings and reo schedule; they do not design the footing system.
Concrete supply: the concrete itself (cubic metres) is typically ordered by the concretor but charged to the client or builder separately. Confirm in the scope of works whether the concretor’s quote includes or excludes concrete material cost.
Pump hire: concrete pumping is sometimes a separate hire item. On constrained sites where direct chute is impractical, a boom pump or line pump is required. Clarify who arranges and pays for the pump.
Reinforcement supply: steel bar and mesh is often supplied by the builder or client and placed by the concretor. Confirm supply side before quoting.
Vapour barrier and termite protection: the underslab vapour barrier (polyethylene sheet) and termite management system are often installed by the builder or a specialist before the concretor begins formwork. Confirm sequence and who supplies.
Sub-base preparation: crushed rock or compacted fill preparation is often civil or earthworks scope, not the concretor. The concretor typically works on a prepared base, not raw ground.
Decorative finishes: exposed aggregate sealing, coloured concrete grinding, or polished concrete finish are typically a specialist finisher, not the concretor who placed the slab.

The scope of works should specify concrete grade, supply responsibility, pump allowance, and sub-base condition at handover. Most variations on concretor packages originate at these supply and preparation lines.

Engagement basics

Licensing, state-by-state

State	Scheme	Key rule
NSW	NSW Fair Trading contractor licence	Required for general concreting work valued over $5,000 in labour and materials (including GST). Qualification: CPC30320 Certificate III in Concreting (or equivalent predecessor). Scope covers formwork, reinforcement fixing, and concreting for dwellings, garages, outbuildings, swimming pools, and concrete retaining walls. Penalties: $22,000 individual / $110,000 company under the Home Building Act 1989 (NSW) (verified 2026-05-10).
QLD	QBCC concreting licence	QBCC concreting licence required. Scope covers installing formwork, reinforcement, and concrete, plus incidental work. Managerial qualification (BSBESB402) required for contractor licence. Minimum financial requirements apply. Fit-and-proper person test applies (verified 2026-05-10).
VIC	Building and Plumbing Commission (BPC)	The BPC (formerly the Victorian Building Authority, transitioned July 2025) regulates building practitioners. Concreting work on residential buildings is typically captured under the building practitioner framework for work over $10,000 requiring a domestic building contract. Verify current registration class and threshold with the Building and Plumbing Commission before quoting (verified 2026-05-10).
WA, SA, TAS, NT, ACT	Each state has its own scheme	Verify current licence class, insurance requirements, and threshold with the state regulator before quoting.

Apprenticeship pathway

Concretors typically complete CPC30320 Certificate III in Concreting (the current qualification, superseding CPC30318) through a registered training organisation (RTO), usually via an apprenticeship combining on-the-tools work with block-release study (verified 2026-05-10).

Insurance the concretor should carry

Public Liability: typical floor $5m for sole-trader residential, $10m when working under a head contractor
Workers Compensation: required for any employees or apprentices
Tool and plant insurance: standard for operators with significant plant (poker vibrator, power float, pump)

Current Certificates of Currency for PL and Workers Comp should be sighted before work starts. The concretor holds them; the engaging party (usually the builder, sometimes the client direct) confirms them.

Pricing basis

Concretor pricing is typically structured two ways:

Per m² (labour only): for slab-on-ground packages with a defined area and standard reinforcement. Rate includes formwork, reo placement, pour, finish, and cure. Does not include the concrete itself, pump hire, or sub-base preparation unless stated.
Lump sum: for the full package on a defined footprint with detailed drawings. Cleaner from a budget control perspective; requires a complete reo schedule and engineer’s design before pricing.

Avoid agreeing to a rate without confirming what the concrete grade is, who supplies the reo, whether a pump is included, and what the sub-base condition is at handover. Each of these is a common variation source.

Tolerances and acceptance

Concrete work is assessed at the pre-pour inspection (before the pour) and at practical completion against the structural drawings, AS 2870:2011, AS 3600:2018, and the HIA Guide to Materials and Workmanship plus the relevant state Guide to Standards and Tolerances.

Standards baseline

AS 2870:2011 sets the design and construction requirements for residential slab and footing systems for Class 1 and Class 10a buildings, covering site classification (A, S, M, H, E, P), footing types, concrete grade minimums, cover to reinforcement, and construction requirements (verified 2026-05-10).

AS 3600:2018 is the structural concrete standard, referenced by the NCC for reinforced concrete elements outside AS 2870’s scope, such as engineered retaining walls and suspended slabs (verified 2026-05-10).

AS 1379:2007 governs the specification and supply of concrete from the batching plant, including minimum strength grade, slump, and delivery requirements (verified 2026-05-10).

AS 3610.1:2018 covers formwork for concrete, specifying documentation, surface finish classifications, and formwork construction requirements (verified 2026-05-10).

Workmanship tolerances (HIA Guide pending)

Numerical limits for slab flatness, finish consistency, and formed surface tolerances are set by the HIA Guide and the relevant state Guide. Values are pending HIA member access.

Item	Guide coverage
Slab surface flatness (F-number or mm deviation)	Per current HIA Guide to Materials and Workmanship and state Guide. Pending HIA member access. [HIA-133]
Slab thickness variation	Per HIA Guide and state Guide. Pending HIA member access. [HIA-134]
Edge beam and kerb alignment	Per HIA Guide and state Guide. Pending HIA member access. [HIA-135]

What can be assessed independently

Concrete grade: the delivery docket from the batching plant confirms the specified grade (e.g. N25, N32) per AS 1379:2007. Check the docket before the truck leaves site.
Cover to reinforcement: AS 2870:2011 sets minimum cover requirements per exposure class. Bar chairs should be correctly sized and spaced. A pocket rod or cover meter can verify before the pour.
Reo layout: the reo schedule on the structural drawings specifies bar size, spacing, and lap lengths. Checked at the pre-pour inspection before the pour is authorised.
Slab level: a laser level check at completion confirms falls to floor wastes and threshold clearances.

Common defects to look for

What inspectors and clients flag at the pre-pour inspection, PCI, and final inspection:

Cold joints: when fresh concrete is placed against concrete that has already begun to set. Caused by delays between batches, excessive time in the truck, or poor coordination with the batching plant. Creates a visible plane of weakness with low bond strength. A structural defect in footings and slabs.
Crazing: a network of fine surface cracks, usually caused by rapid moisture loss from the surface during finishing. Typically cosmetic but can be a precursor to deeper surface degradation if the curing regime was inadequate.
Plastic shrinkage cracking: parallel surface cracks appearing within hours of placement, caused by high evaporation rates (wind, heat, low humidity) exceeding bleed water supply before the concrete sets. Shallow and typically not structural, but unsightly and a PCI call.
Laitance: a weak, milky layer of cement paste, water, and fines that accumulates at the surface when the concrete is over-vibrated, has a high water-cement ratio, or bleed water is worked back in during finishing. The surface looks smooth but bonds poorly and dusts easily. Common on paths and driveways.
Honeycombing: voids left in formed concrete (footings, retaining walls) where aggregate is not surrounded by paste. Caused by inadequate compaction or vibration. Structural severity depends on location and extent.
Inadequate cover: reinforcement placed too close to the surface. Causes rust staining and spalling as moisture penetrates. Only reliably checked before the pour; once concrete is placed, it’s a cut-and-core to verify.
Surface blistering: bubbles of entrapped air or water trapped under a prematurely sealed surface. Caused by finishing the surface before bleed water has fully evaporated, typically in hot or windy conditions.

Most pour-related defects (cold joints, inadequate cover, honeycombing) are only addressable before the concrete sets. The pre-pour inspection is the last chance to fix formwork and reo before the pour is locked in. After the pour, remediation is core-drilling, patching, or full break-out.

Subbie quote pack, what should be in it

A complete concretor quote pack covers:

Scope: which concrete elements are in (slab, footings, paths, driveways, retaining walls), which are explicitly out; supply boundaries for concrete, reo, pump, formwork, sub-base, vapour barrier
Concrete specification: grade (N25, N32, or other), slump, admixtures if any; batching plant confirmed
Reinforcement: who supplies bar, mesh, bar chairs, tie wire; who places and fixes
Pump allowance: included or excluded; if excluded, who arranges and pays
Finish specification: broom, trowel, power float, exposed aggregate; level and falls confirmed
Pricing basis: lump sum or rate per m²; what is and isn’t in the rate
Programme commitment: pour date, curing period before loading, dependencies (sub-base ready, engineer’s inspection complete, certifier booked)
Licence and insurance: contractor licence number, Certificates of Currency for PL and Workers Comp
Site obligations: SWMS for formwork and concrete works, WHS obligations, concrete washout procedure
Variation mechanism: how unscoped work is priced; written authorisation required

The same list reads from different sides:

For the engaging party (builder or client direct): use this list as the quote template. Require all items before signing.
For the concretor quoting: providing all of these without being asked wins jobs and reduces disputes.
For the client reviewing a builder’s engagement: this is the bar the builder should be applying.

References

AS 2870:2011 Residential slabs and footings (Standards Australia) (verified 2026-05-10)
AS 3600:2018 Concrete structures (Standards Australia) (verified 2026-05-10)
AS 1379:2007 Specification and supply of concrete (Standards Australia) (verified 2026-05-10)
AS 3610.1:2018 Formwork for concrete, Part 1: Specifications (Standards Australia) (verified 2026-05-10)
NSW Government: General concreting work licensing (verified 2026-05-10)
QBCC: Concreting licence (verified 2026-05-10)
Building and Plumbing Commission (VIC) (verified 2026-05-10; VBA transitioned to Building and Plumbing Commission July 2025)
CPC30320 Certificate III in Concreting (training.gov.au) (verified 2026-05-10)
HIA Guide to Materials and Workmanship, pending member access for numerical workmanship tolerances
NCC 2022 Volume Two for Class 1 and Class 10 buildings, ABCB (verified 2026-05-10)