How to Choose a Concreter in Adelaide (And Avoid Costly Mistakes)

(copy exactly)

Title: How to Choose a Concreter in Adelaide (And Avoid Costly Mistakes)

---

A concrete driveway or slab should last 25–40 years. Choosing the wrong contractor can turn that into a 5-year nightmare of cracking, settling, and costly repairs. Here's what to look for — and what to walk away from.

---

Step 1: Check the SA Builder's Licence

In South Australia, any work over $10,000 in value must be performed by a licensed builder. Concrete driveways, patios, and slabs almost always exceed this threshold once you factor in labour and materials.

The licence to look for is a Building Work Contractors Licence (BWCL), issued by Consumer and Business Services SA (CBS). You can verify any contractor's licence at the CBS website.

What to check:

• Is the licence current? (Not expired or suspended)
• Does the licence category cover concreting work?
• Is the trading name the same as the company name on the licence?

If a contractor can't provide their licence number — or their number doesn't check out — walk away.

Opal SA Construction licence: BLD 317725 — verify at cbs.sa.gov.au.

---

Step 2: Ask About Soil Class and Reinforcement

This is the question that separates experienced Adelaide concreters from the rest.

Adelaide's soils range from non-reactive coastal sands (Glenelg, Brighton) to highly reactive clays in the northern suburbs (Salisbury, Elizabeth, Gawler) and parts of the south (Morphett Vale, Reynella). Reactive clay expands when wet and contracts when dry, exerting substantial pressure on any concrete structure above it.

Under AS 2870, slabs and footings must be designed to match the site's soil class. For driveways, this means:

• On Class H1 or H2 soils: thicker slab (125–150mm), heavier reinforcement (F82 mesh or bars), and sometimes a granular sub-base to manage moisture
• On Class M soils: standard 100–125mm slab with F72 mesh is sufficient
• On Class A or S soils: minimal special measures required

If you ask a prospective concreter "what soil class is this area?" and they look blank — that's a problem. It means they're likely pouring the same slab everywhere regardless of ground conditions.

---

Step 3: Get 3 Written Quotes

Three quotes gives you a market reference. You're not necessarily looking for the cheapest — you're looking for a quote that:

Is itemised (concrete volume, reinforcement spec, finish, preparation)

Is GST-inclusive

Specifies the concrete strength (MPa) and slab thickness

States what's not included

Includes a timeline and payment schedule

Red flags in a quote:

• No GST breakdown
• "Price may vary" without specifying why
• No mention of reinforcement
• No specification of concrete mix strength
• Verbal-only quote (no written document)
• Requires a large cash deposit upfront

---

Step 4: Ask Who Is Doing the Work

This is one of the most important questions you can ask — and most homeowners don't.

Some concrete contractors quote your job and then hand it to a subcontractor. The person who did the sales visit may never set foot on your property again. Subcontracting isn't inherently wrong, but it means:

• Less accountability if something goes wrong
• The sub may have different skill levels and equipment
• Quality control is harder for the head contractor

Ask directly: "Will your own crew be doing this job, or will you be subcontracting it out?"

At Opal SA Construction, every job is done by our own trained crew. Javed oversees each project personally.

---

Step 5: Check Insurance

Any contractor working on your property should carry:

• Public Liability Insurance — covers damage to your property or injury to a third party during the works
• Workers' Compensation — covers their workers if injured on your site

Ask for a Certificate of Currency before works start. A legitimate contractor will provide this without hesitation. If they can't — they may not be insured, which exposes you to significant liability.

---

Step 6: Look at Past Work

Ask to see photos of completed jobs — specifically in your suburb or nearby. Adelaide's soil variation means a concreter with experience in your area will already know the ground conditions, common drainage directions, and council requirements.

If possible, ask for a reference from a recent local customer. A good contractor will have satisfied customers happy to talk.

---

Step 7: Understand the Warranty

What does the contractor warrant? Minimum expectations:

• Structural warranty: 6–10 years against defective workmanship (major structural failures)
• What's covered: cracking beyond control joints, surface delamination, significant settlement
• What's not covered: surface marking from tyre scuffing, hairline control joint cracking (this is normal), staining

Ask to see the warranty in writing before signing.

Opal SA Construction provides a 10-year structural warranty on all concrete work.

---

Common Mistakes Adelaide Homeowners Make

Choosing on price alone

The cheapest quote is usually cheap for a reason — thinner slab, less reinforcement, cheaper concrete mix, or an unlicensed operator. The price difference between the cheapest and second-cheapest quote is often $800–$1,500 on a standard driveway. The cost of repairs if the cheap job fails is $5,000–$15,000+.

Not asking about drainage

Concrete must slope away from the house. On a flat site, this requires the formwork to be set with a deliberate fall. Without it, water ponds against the foundation — causing damp problems, concrete spalling, and in severe cases, undermining the slab edge.

Not checking if a permit is needed

Most residential concrete patios and driveways don't need a Council permit. But kerb cuts, retaining walls, and slabs supporting structures often do. Don't assume — check before work starts, or ask your contractor to check for you.

Accepting a verbal quote

Get everything in writing: scope, specification, price, payment terms, and warranty. If a contractor won't put it in writing, they won't honour it if something goes wrong.

---

Questions to Ask Every Concreter You Invite to Quote

What is your SA builder's licence number?

Do you carry public liability and workers' compensation insurance?

What soil class is this area and how does that affect your quote?

What concrete mix strength (MPa) and slab thickness do you recommend?

What reinforcement is included — mesh type and size?

Will your own crew do the work, or will you subcontract?

What is your warranty on labour and materials?

Can I see photos of similar work you've completed nearby?

If a concreter can answer all eight questions confidently and in writing — they're worth considering.

---

Talk to Opal SA Construction

We're happy to answer all eight of those questions — and anything else you want to know — before you decide whether to engage us. No pressure, no sales tactics.

SA Licence BLD 317725 · Fully insured · Own crew · 10-year structural warranty.

Call Javed: 0466 801 058 or request a free site quote.

---

FAQs

Does a concreter need a builder's licence in SA?

Yes — any building work over $10,000 requires a licensed builder in South Australia. Concrete driveways and slabs almost always exceed this threshold. Check at cbs.sa.gov.au using the contractor's licence number.

How many quotes should I get for concrete work?

Three is the standard recommendation. One quote gives you no reference point; two is a coin flip; three gives you a real market picture. Be suspicious of quotes that are 30%+ below the others.

What should I do if concrete work goes wrong?

First, contact the contractor in writing and give them the opportunity to rectify the issue under warranty. If they don't respond within a reasonable time (14 days), you can lodge a complaint with Consumer and Business Services SA. If the contractor was licensed, CBS has investigative powers and can require rectification.

---

Published: 10 May 2026 · Opal SA Construction · BLD 317725