Inspections

Slab Stage Inspection Checklist

Pre-payment checklist for your concrete slab stage. Covers reinforcement, drainage, waterproofing, dimensions, and concrete finish before you release progress payment.

Slab Stage Inspection Checklist

Pre-payment checklist for your concrete slab stage. Covers reinforcement, drainage, waterproofing, dimensions, and concrete finish before you release progress payment.

When to use this checklist: Use this before releasing your slab-stage progress payment. Your builder cannot cover the slab until you (or your inspector) have approved it. If you find defects, list them in writing before signing off. Do not release payment until all items are satisfactory.

📋 Documentation to request

Engineer's footing and slab design — confirm it matches what was poured

Soil report (geotechnical report) — confirm site classification matches design

Council-approved plans — compare slab layout and dimensions

Waterproofing installer certificate (if required for your slab type)

Termite protection certificate (if chemical barrier used at slab stage)

🏗️ Site preparation

Site is level and compacted — no loose fill, soft spots, or low areas that could settle

Fill material (if used) is engineered fill, not construction waste or topsoil

Formwork removed or correctly positioned before pour

No standing water in trenches or on site before pour

Termite protection system installed before concrete pour (check certificate)

Vapour barrier (polythene membrane) installed under slab — no tears or gaps

🔩 Steel reinforcement

Rebar or mesh size matches engineer's specification

Bar spacing consistent throughout — no skipped areas

Reinforcement tied or clipped — no loose bars that could shift during pour

Concrete cover (distance from steel to surface) correct — typically 40–75 mm for slabs

Chairs or spacers used to hold steel at correct height — not sitting on ground

Reinforcement extends into edge beams and footings correctly

No rust or scale on steel beyond surface oxidation (light rust is acceptable, flaking is not)

Extra reinforcement at corners, penetrations, and re-entrant corners

🔧 Plumbing and drainage

All in-slab plumbing pipes in correct locations — match plumbing plan

Pipe penetrations through slab sleeved correctly

Floor waste positions match bathroom, laundry, and kitchen plan

Sewer and stormwater connections made at correct location and depth

Storm water pits and agricultural drains in position before pour

No unsupported pipes that could shift during pour

Plumbing inspection sign-off (council or certifier) obtained where required

🪨 Concrete finish and quality

Slab thickness — measure in several locations using a probe or at visible edges; matches spec

Concrete grade matches engineer's specification (e.g. N25, N32)

Surface finish is smooth and even — no honeycombing (porous voids), cold joints, or major pop-outs

No cracking beyond normal shrinkage hairlines (hairline < 0.2 mm is acceptable)

Control joints (saw cuts) placed at correct spacing and within 24 hours of pour

Slab edges straight and consistent height

No delamination — press firmly across surface, no hollow sound under foot

Curing compound applied or wet curing used — surface not allowed to dry out rapidly

📐 Dimensions and setbacks

Overall slab dimensions match approved plans — measure length and width

Setback from boundary correct — measure front, rear, and both sides

Slab is square — measure both diagonals; difference should be under 20 mm

Floor level (FFL) at correct height relative to datum peg and natural ground level

Step-downs in slab (alfresco, garage) at correct depth

Garage slab at correct fall toward front — typically 1:100

All room sizes match plan dimensions — measure at least 3 rooms

📏 Edge beams and footings

Perimeter edge beams at correct depth — matches engineer's design

Internal stiffening beams (if required) at correct depth and spacing

No voids under edge beams — check by pushing a rod under the slab perimeter

Footing depth correct at step-down zones and re-entrant corners

No formwork boards or debris left under slab

📝 Defects noted on inspection

Track defects digitally with Checka

This checklist helps you spot issues. Checka helps you document them with photos, share reports with your builder, and track what gets fixed.

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