C6 Concrete Slab Inspection Checklist for Homeowners

C6 at a glance

Post-Pour Slab Inspection: what to check once the slab is poured

61checks

8sections

3result options

14pages

Records first (S1 and S2). Dockets, inspections and curing, then a quick look at the site.

On the slab (S3 to S6). Edges, levels, pipes and cracks, with a tape and the plans. Tick Fine, Later (not yet) or Issue.

Before the frame (S7 and S8). Your list to the builder in writing, with photos. S8 lists what your builder should be doing: ask to see the records.

The 8 sections

S1Pour day recordsSteel inspection, concrete grade and slump on dockets, truck times, volume, plumbing test, pour photos, signed changes8
S2Curing and the siteCuring method and timing, compound suits floor finishes, no loads on the slab, washout, kerb damage, sediment fence8
S3Slab edges and rebatesSolid, plumb edges with no honeycombing, 20 mm brick rebate, membrane at the edge, 150 mm above ground, garage rebate8
S4Levels, square and set-downsOutside dimensions and diagonals, floor level to plans, flat within 10 mm per room, set-downs placed and deep enough4
S5Pipes, bolts and jointsPipe positions to layouts, capped pipes, termite collars, tie-down bolts, pier pads, conduits, earthing, saw-cut joints9
S6Cracks and surfaceFinish by area, crack widths measured, cracks under 1 mm with no step, no dusting, scaling or ponding4
S7Before the frameEngineer's repair details, back-props kept in, photos with a tape in shot, your list sent in writing within two days5
S8What your builder should be doingSediment control, signs and toilet, power and water on, framing plans, pods collected, docket volumes, props off-hired15

Short on time? The “Check these 10” card on page 2 has the checks that matter most, and the “Documents to collect” box lists what to ask for. Use it straight after the slab pour and before framing starts. Educational guide only.

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Introduction

Building a home is one of the biggest investments you'll ever make, and the post-pour slab inspection is one stage you don't want to skip. The pre-pour inspection (our C5 Checklist) is arguably the MVP of stage inspections, but the post-pour check is just as essential.

Once the concrete is down, it's time to see what really happened. Did the pour go to plan? How was it finished? Did a concretor kick a pipe over by accident? It's far cheaper to catch problems now than after the frame is up.

In this post, we introduce our C6 Post-Pour Slab Inspection Checklist designed specifically for residential homes.

We'll also cover sediment and erosion control (ESC), the measures that stop soil washing off your site, and how the slab is assessed against AS 2870 (Residential slabs and footings) and the QBCC Standards and Tolerances Guide.

C6 - Post Pour Slab Inspection Checklist

$59.00 AUD

Last updated 28 Oct 2026 · Revision 4 · Free updates for life

Checklist Type: Minor

Form Factor: Fillable, print-ready PDF (A4, 21 pages)

When to use: After the concrete pour, before the frame goes up

A 61-point checklist to inspect your slab after the pour: records, curing, edges, levels, pipes and cracks, while repairs are still easy to arrange.

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What Is the Post-Pour Concrete Slab Inspection Checklist?

The C6 Post-Pour Slab Inspection Checklist helps homeowners, builders and project managers check the quality and compliance of a freshly poured house slab. It breaks the inspection into simple steps you can follow without being a construction expert. It follows on from our C5 Pre-Pour Inspection checklist:

First comes our C5 checklist then post pour, use our C6 checklist - for a buttery smooth slab surface finish 😄

Purpose of the Checklist

The checklist helps you find common problems straight after the pour, before the next stages start, such as:

Misalignment or unevenness in the slab that affects the framing stage.
Poor-quality finishes that compromise the slab’s longevity.
Incorrectly installed damp-proof membranes, which can lead to moisture ingress.
Non-compliance with sediment and erosion control (ESC) regulations, potentially resulting in fines or environmental harm.

Structure and Scope

The checklist is divided into several key areas of focus:

Site Management: Ensuring the construction site is organised, safe, and compliant with sediment control measures.
Concrete Features and Finishes: Checking the slab's flatness, levelness, curing and finishes against AS 2870 and the QBCC Standards and Tolerances Guide.
Erosion and Sediment Control: Checking that ESC measures are properly implemented to prevent runoff and sedimentation issues.

Quality control at this stage of construction is essential for avoiding:

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Did you know? Addressing slab issues early can save you thousands in repair costs and weeks in construction delays.

Key Terms Defined

Here are the key terms used in the checklist.

1. Sediment and Erosion Control (ESC)

ESC refers to measures implemented to prevent soil, sand, and construction debris from being washed into stormwater drains or neighbouring properties. These measures include sediment fences, straw wattles, and stockpile covers, all of which are important for compliance with environmental regulations.

2. Concrete Curing

Curing is the process of maintaining adequate moisture in the poured concrete to ensure it achieves its desired strength and durability. Common curing methods include applying curing compounds, sprinkling water, or using damp coverings like hessian or plastic sheets.

3. Green Concrete

Green concrete is freshly poured concrete that hasn't reached full strength yet. Most fixes are easiest in the first week, while the concrete is still gaining strength.

4. Tolerances (Flatness and Levelness)

Tolerances are the acceptable limits of variation in the slab surface. The QBCC Standards and Tolerances Guide (2023, clause 3.8) says a new concrete floor is defective if, within 12 months of completion:

Level within a room: it differs in level by more than 10mm in any room or area.
Level over a length: it differs by more than 12mm in any 3m length.
- The overall deviation of floor level to an entire building footprint shall not exceed 20mm within 12 months.

5. Damp-Proof Membrane (DPM)

A plastic sheet laid under the slab to stop ground moisture coming up through the concrete into the house. It must be intact, properly lapped, and run out to the slab edge.

6. Penetrations

These are openings in the slab for plumbing, electrical, or other services. They must remain plumb (vertical) and properly sealed or capped to prevent water ingress and termite infestation.

7. Termite Protection

Measures such as chemical barriers or physical seals applied around slab penetrations to prevent termites from entering the structure through gaps in the concrete.

8. Erosion Rills

Small channels or streamlets carved into exposed soil by running water. These can indicate poor erosion control on the site.

9. Control Joints

Deliberate weak lines cut or formed in the slab so that, as the concrete dries and shrinks, it cracks along the joint rather than randomly. Learn more about the different types of concrete joints in our post below.

10. Curing Compounds

Specialised chemical products applied to the slab surface to retain moisture during the curing process. They help prevent premature drying, which can lead to cracking.

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Quick Tip: If you’re unsure about technical terms, ask your contractor to explain them on-site—don’t be afraid to ask questions!

Essential Checks After Pouring the Slab

The post-pour inspection is your chance to deal with problems before they get expensive. Work through the slab and the site systematically.

Site Management Items

Here's what to check on site:

Sediment Fences: Ensure that sediment fences are upright, intact, and effectively preventing runoff. Damaged or improperly installed fences can lead to environmental fines.
Road Kerbs and Gutters: Verify that streets and drainage areas are free of sediment and debris. Sweep as necessary to maintain compliance.
Signage and Security:Confirm that all required safety signs are visible from the street.Ensure the site is secure to prevent theft or vandalism.
Neighbouring Properties: Check for any accidental damage to neighbouring yards, fences, or structures. Document issues with photos and address them promptly.

Concrete Features and Finishes

Concrete quality and adherence to specifications are critical for a durable slab. Pay close attention to these elements:

Flatness and Levelness:
Use a laser or long spirit level to check the slab against the QBCC tolerances: no more than 10mm out of level in any room or area, or 12mm in any 3m length. Sort out anything outside these limits before framing starts.
Curing:
- Confirm that curing methods are applied, such as water sprinklers, damp coverings, or curing compounds. Proper curing prevents surface cracking and ensures long-term strength.
Damp-Proof Membrane:
Check the DPM is intact (no tears), properly lapped, and runs out to the slab edge as the engineer's details and AS 2870 require. This protects the house from rising moisture.
Building Dimensions: Check the slab dimensions against the plans. The QBCC guide treats a departure of more than L/200 (L = the documented length) or 5mm, whichever is greater, as a defect.
Finished Floor Levels: Finished Floor Levels (FFL) or Reduced Levels (RL) are defective if they depart from the documented FFL or RL by more than 40mm.

Penetrations and Termite Protection

Service penetrations, such as pipes and conduits, require careful inspection:

Alignment:
- Ensure all penetrations remain vertical (plumb) and are capped or taped to prevent debris ingress.
Termite Barriers:
- Confirm that termite protection measures around penetrations are intact and covered in concrete. Any gaps can compromise termite resistance.

Erosion and Sediment Control (ESC)

Sediment and erosion control measures help protect the environment and prevent regulatory penalties:

Drainage:
- Inspect sediment traps, fences, and straw wattles for proper installation and maintenance. Check for any signs of water bypassing these measures
Stormwater Inlets:
- Confirm that all stormwater inlets are safeguarded against sediment infiltration. Clear any blockages immediately.

Visual Inspection and Documentation

A visual inspection can reveal issues that measurements might miss:

Edge Finishes:
- Walk the slab perimeter to ensure edges are straight, clean, and properly sponged or vibrated to avoid pitting.
Photos and Notes:
- Take photos from multiple angles, around the site including the front of the site clearly showing the sediment fence installation and ensuring the builder's & safety sign is visible.
- Use fluro line marker paint to highlight areas requiring repair for clear communication with contractors.
- Only use marking paints, crayons and the like when it will not affect future floor coverings or systems - like grinding or honing. Check with the suppliers to ensure product compatibility before using markers and applied products on slabs to ensure there is not a reaction or it creates further issues. Examples of surface finishes that may be affected by builders crayons are polished concrete and some vinyl flooring.

If anything significant turns up, document it thoroughly and contact your builder straight away.

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A flat and level slab isn’t just about looks—it’s the foundation for everything else in your home. Get it right, right from the start!

Common Post-Pour Issues

Even with a detailed checklist, problems happen. Here are the common post-pour issues and how to manage them.

1. Slab Flatness and Levelness

Issue: The slab is uneven or slopes incorrectly, outside the QBCC tolerances (10mm in any room, or 12mm in any 3m length). Even a slab inside tolerance can be too uneven for large rectified-edge tiles, so allow for floor preparation (grinding and levelling) in your budget.
Solution:
Use a laser, a long spirit level, or a long straight edge with a spirit level to find problem areas. Mark them and discuss options with your builder, such as grinding high spots or filling low areas, including the products, cost and timing. Verbal agreements cost money. Get the fix, who does it and when in writing.

2. Inadequate Curing (Hot Weather Curing)

Issue: The slab surface shows signs of premature or rapid drying, such as cracks or flaking.
Solution:
- Ensure curing compounds are applied or water curing is initiated immediately. If the concrete has already started cracking, consult with your contractor about applying a surface sealer or repairing the affected areas.

3. Damp-Proof Membrane (DPM) Misplacement

Issue: The DPM does not extend sufficiently beyond the slab edge or has been damaged during the pour.
Solution:
Look for tears or poor laps in the membrane and ask for repairs. If the DPM doesn't reach the slab edge, your builder needs an edge treatment approved by the structural engineer or a waterproofing consultant (for example a penetrating or cementitious waterproofing system). Ask for it in writing before any work starts, because the real question is who carries the liability if it goes wrong.

4. Termite Barrier Gaps

Issue: Gaps are visible between concrete and penetrations, compromising termite protection.
Solution:
- Add or repair termite collars around penetrations and ensure they are sealed with concrete.
- Termite sealants are available - just hard to find sometimes.
- Depending on the extent of the gaps, concrete scabble, cutting may be required to reset protection and allow sufficient coverage over the repair to prevent fouling of future floor coverings.

5. Edge Finishes and Surface Defects

Issue: Slab edges are pitted, irregular, or improperly finished, which can impact aesthetics and durability.
Solution:
Sponging or grinding can smooth rough edges and pitting. Any filling or patching of slab edges should only be done as directed by the structural engineer, and if there's excessive honeycombing (voids where the concrete didn't fill properly) or cold joints, the engineer needs to look at it.

6. Sediment and Erosion Issues

Issue: Soil or construction debris has washed into stormwater drains or neighbouring properties, violating sediment and erosion control (ESC) regulations.
Solution:
Clear blocked drains and repair sediment fences. Check the kerb and channel is clear and that sediment fences are trenched in, taut and upright. Make sure vehicle access and parking areas have 40-50mm gravel to stop mud being tracked onto the road.

7. Excess Concrete and Debris

Issue: Excess concrete has been dumped on-site, or debris remains uncollected, creating safety hazards.
Solution:
Arrange removal of waste and leftover concrete. Breaking up excess green concrete before it fully sets can save on machine hire and disposal later. Sweep kerbs and roads to avoid council fines, and note any over-ordering so future deliveries are adjusted.

8. Cracking in Green Concrete

Issue: Hairline cracks have appeared in the slab before it has fully cured.
Solution:
- Minor hairline cracks can often be monitored, but significant cracks may require filling with epoxy or other sealants. Discuss with your contractor to assess the severity and ensure it won’t affect structural integrity.
How big is your crack?

Damage categories for concrete floors
Category	Crack width	Out of level over 3 m	What it looks like
0 Negligible	under 0.3 mm	under 8 mm	Hairline cracks
1 Very slight	under 1 mm	under 10 mm	Fine but noticeable cracks
2 Slight	under 2 mm	under 15 mm	Distinct cracks, slab noticeably curved
3 Moderate	2 to 4 mm	15 to 25 mm	Wide cracks, obvious curvature
4 Severe	4 to 10 mm	over 25 mm	Gaps in slab, disturbing curvature

Summarised in our words from AS 2870 Appendix C. Check the current edition.

9. Documentation and Follow-Up

Issue: Issues identified during the inspection are not being addressed promptly by contractors.
Solution:
- Keep detailed records of all identified problems, including photos and written notes. Follow up with contractors via email and phone, ensuring you have a record of all communications.

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Most issues are easiest to fix when the concrete is still green—don’t wait too long to act!

How to Manage Erosion and Sediment Control (ESC)

Erosion and sediment control isn't just a council requirement. It protects neighbouring properties and stormwater drains, and poor ESC can mean fines and delays. Here's what to check after the pour. Our C3 Sediment and Erosion Control checklist (linked below) covers it in detail.

Sediment Fences:
- Check for proper installation and no signs of damage or sagging.
- Confirm that sediment fences effectively trap debris while allowing water to flow through.
Stormwater Drain Protection:
- Inspect drains for sediment infiltration. If sediment traps are installed, ensure they are functional and not clogged.
Site Cleanliness:
- Verify that concrete slurry, debris, and washout are confined to the designated areas and not entering drains
Stockpile and Soil Protection:
- Ensure that any soil stockpiles are securely covered with tarpaulins or erosion-control mats to prevent wind and water erosion.
Driveway and Kerb Areas:
- Confirm that the road and kerb are swept clean of debris, and erosion control measures (such as straw wattles) are protecting the edges.
Divert clean water away from the site using temporary drainage channels.
Install and maintain spoon drains to manage water flow across the site.

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Inspect after every storm! Heavy rain can undo even the best erosion control measures, so regular checks are a must.

Wastewater Management:
- Prevent wastewater from trades (such as concrete washout) from entering stormwater drains. Use designated washout stations instead.

Read our blog post on ESC and get our ESC checklist below:

Tips for Documenting and Communicating Issues

Clear records and early communication prevent misunderstandings, delays and disputes.

1. Take Detailed Photos

Capture All Angles: Photograph the slab from multiple perspectives, ensuring that key features like penetrations, edges, and finishes are clearly visible.
Highlight Issues: Use a line marker or tape to indicate areas of concern in your photos. This visual aid helps contractors quickly identify the problem.
Include Context: Ensure that each photo includes identifiable elements, such as the builder's sign or surrounding landmarks, to provide context.

2. Maintain Comprehensive Notes

Record Observations: Write down specific details about each issue, including its location, nature, and potential impact on the project.
Use Checklists: Tick off completed items on the inspection checklist and annotate any delays, follow-ups, or unresolved issues.

3. Communicate Clearly with Contractors

Use Multiple Channels:
- Follow up verbal discussions with written communication, such as emails or text messages, to maintain a clear record.
- Attach annotated photos and checklist entries to ensure clarity.
Be Prompt: Notify contractors of any issues immediately to prevent delays in remedial work.

4. Focus on Resolution

Provide Clear Instructions: Specify the corrective actions you expect for each identified issue.
Set Deadlines: Request that repairs or adjustments be made within a reasonable time frame, especially if the slab is still green and corrections are easier to perform.

5. Keep a Risk/Issue Log or Communication Register

Track Actions: Maintain a log of all communication and follow-ups, including the date, time, and nature of each interaction.
Monitor Progress: Revisit the site as necessary to verify that issues have been resolved and document the changes.

6. Be Prepared for Escalation

If contractors fail to address critical issues:

Engage a Third Party: Consider hiring an independent building inspector to assess the slab and provide recommendations.
Escalate Through Formal Channels: If necessary, escalate the matter with your builder, and if that fails, the QBCC.

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"Photo-Photo" - Take photos, take notes, take charge. The more detail you record, the easier it is to resolve issues later.

Conclusion

A post-pour slab inspection is your chance to catch small problems before they become big, expensive ones. Check the levels, the penetrations, the membrane and the site controls, write everything down, and keep talking to your builder. Don't worry if some of it feels technical. With the checklist in hand, you'll know what to look for.

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“Don’t forget to revisit the site! A follow-up inspection ensures that reported issues are resolved and nothing is missed.

Support the CSIRO

Support the CSIRO and grab a copy of their Footing Performance and Maintenance Guide (view-only version linked below).

While your builder might hand it over at the end of construction, why wait?

Get it early, read it, and actually apply it to your home. Don't let it gather dust in the handover folder.

Test yourself

Five quick questions on this topic. Click a question to see the answer.

Why is curing important for concrete?

It controls the loss of moisture and allows ongoing hydration of cement.

What is one method mentioned for maintaining a continuously wet surface during concrete curing?

Ponding or spraying the surface with water.

What is the consequence of loss of moisture and/or cement grout through formwork?

Honeycombing.

Why should PVA-based bonding agents be avoided in locations where concrete may become wet?

They tend to re-emulsify in wet conditions.

Why is it important to limit the temperature rise in concrete?

To avoid thermal cracking.

FAQs

1. Why is a post-pour slab inspection important?
A post-pour inspection ensures your slab meets Australian standards (like AS2870) and is free from defects that could cause delays, extra costs, or structural issues later on.

2. What tools do I need for a slab inspection?
A spirit level, laser level, tape measure, line marker, a camera or smartphone for photos, and a copy of the checklist will be your best tools.

3. How soon after pouring should the slab be inspected?
You should inspect the slab within 24–48 hours of the pour. This is when any immediate issues, like flatness or curing problems, can be most effectively addressed.

4. What are the acceptable tolerances for slab levelness?
Under the QBCC Standards and Tolerances Guide, a new concrete floor is defective if it's more than 10mm out of level in any room or area, or more than 12mm in any 3m length, and the overall deviation across the building footprint can't exceed 20mm within 12 months of completion.

5. How do I check for termite protection around slab penetrations?
Look for termite collars or chemical barriers around any pipes or conduits penetrating the slab. These should be sealed in concrete without gaps.

6. What should I do if I find cracks in the slab?
Hairline cracks (under 0.3mm) are classed as negligible under AS 2870. Larger cracks may need professional assessment, and your builder may need to repair them with epoxy or other fillers.

See 8. Cracking in Green Concrete (above) and the section below on plastic shrinkage cracking.

7. What are the penalties for not complying with sediment and erosion control (ESC) measures?
Non-compliance with ESC regulations can lead to fines from local councils or environmental authorities, as well as costly remediation work.

8. How do I document issues effectively during the inspection?
Take clear photos from multiple angles, mark problem areas with spray paint or tape, and write down detailed notes about the issue and its location.

9. Can I perform the inspection myself, or do I need a professional?
Homeowners can perform most of the inspection using the checklist, but for complex issues or peace of mind, you may want to hire an independent building inspector.

10. What should I do if my contractor ignores the issues I report?
Escalate it with your builder in writing. If that doesn't work, contact the QBCC. An independent inspector's report can support your case.