Concrete Inspection Checklist (What Inspectors Look For)

Building inspectors verify that your concrete work meets local codes before you pour (pre-pour inspection) and sometimes after completion (final inspection). They're checking for proper dimensions, adequate base preparation, correct reinforcement placement, and compliance with approved plans. Knowing what they look for helps you prepare for a successful concrete pour.

Failing an inspection means fixing issues before the pour can proceed—which is far better than discovering problems after concrete sets.

When Inspections Happen

Pre-Pour Inspection (Most Critical)

Conducted after forms and reinforcement are in place, but before concrete is poured. This is your last chance to fix issues.

Timing: Schedule 24-48 hours in advance. Inspector must see and approve before concrete trucks arrive.

Post-Pour / Final Inspection

Some jurisdictions require a final inspection after the concrete cures (usually 7+ days later). This verifies the completed work matches approved plans.

Timing: Schedule once concrete has cured sufficiently to walk on safely.

Pre-Pour Inspection Checklist

Inspectors verify these items before approving the pour:

Forms and Dimensions

Item	What They Check	Common Issues
Dimensions match permit	Measure length, width	Wrong size
Proper thickness	Depth of forms	Too thin
Forms are square	Diagonal measurements	Corners not 90°
Forms are level/properly sloped	Level or string line	No drainage slope
Forms are secure	Stakes, bracing	Weak or insufficient
Setback compliance	Distance from property lines	Too close to lines

Base Preparation

Item	What They Check	Common Issues
Subgrade compacted	Visual, probing	Soft spots, loose soil
Gravel base (if required)	Thickness, material	Too thin, wrong material
Proper slope for drainage	Grade	Water would pool
No organic material	Roots, debris	Vegetation present
Vapor barrier (if required)	Plastic sheeting	Missing or torn

Reinforcement

Item	What They Check	Common Issues
Rebar size correct	Measure diameter	Wrong size (#3 vs #4)
Rebar spacing correct	Measure centers	Too far apart
Rebar positioned correctly	Chairs/supports	Sitting on ground
Wire mesh (if used)	Overlap, placement	Insufficient overlap
Clearance from forms	Edge distance	Too close to edges
Tied properly	Connections	Loose or missing ties

Rebar positioning: Rebar must be supported to sit in the lower third of the slab, not on the ground. Chairs or dobies (concrete supports) hold it at proper height.

Drainage and Slope

Item	What They Check	Common Issues
Surface drainage	Slope direction	Toward building
Slope percentage	Level/string	Insufficient slope
Connection to drainage	Existing systems	Conflicts or blockages

Typical slope: 1/8" to 1/4" per foot away from structures.

Common Inspection Failures

Failure: Rebar on the Ground

Problem: Reinforcement is laying on the subgrade instead of elevated.

Why it matters: Rebar needs to be in the lower third of the slab to work. On the ground, it does nothing.

Fix: Add chairs/dobies to raise rebar before inspection.

Failure: Forms Not Square

Problem: Corners aren't 90 degrees; diagonals don't match.

Why it matters: Creates crooked slab; may violate setback requirements.

Fix: Use 3-4-5 triangle method. Adjust stakes until diagonals are equal.

Failure: Insufficient Base Compaction

Problem: Subgrade is soft or shows footprints.

Why it matters: Settlement and cracking after pour.

Fix: Compact soil properly; add and compact gravel base.

Failure: Wrong Thickness

Problem: Form depth doesn't match permitted thickness.

Why it matters: Thinner concrete won't support intended loads.

Fix: Adjust forms to proper depth before pour.

Failure: Setback Violation

Problem: Slab is too close to property line.

Why it matters: Violates zoning code; could require removal.

Fix: Adjust forms to meet setback requirements. May need revised permit.

Failure: No Vapor Barrier

Problem: Code requires vapor barrier but none is installed.

Why it matters: Moisture issues in enclosed spaces.

Fix: Install 6-mil polyethylene; overlap seams 6 inches.

How to Schedule an Inspection

1. Call the building department or use their online scheduling system
2. Provide your permit number and address
3. Request "pre-pour concrete inspection"
4. Confirm date and time window (often morning or afternoon, not exact time)
5. Be ready when inspector arrives—don't schedule concrete delivery until after approval

Lead time: Most jurisdictions need 24-48 hours notice. Some require more.

What to Have Ready

Documents

• Approved permit and plans (on site)
• Contractor license info (if applicable)
• Property survey (if setbacks are close)

Site Conditions

• Site accessible to inspector
• Forms complete and ready to pour
• Reinforcement installed and visible
• Base preparation complete
• No standing water

Knowledge

• Know your permit requirements
• Know your lot's setback distances
• Be able to answer basic questions

What If You Fail?

1. Don't panic. Failures happen; that's why we inspect before pouring.
2. Ask what needs to be fixed. Get specific requirements.
3. Make corrections. Fix exactly what the inspector noted.
4. Re-schedule inspection. Usually can be same day or next day.
5. Get approval. Only pour after passing inspection.

Cost of failure: Re-inspection fees are typically $25-75, plus any material/labor to fix issues.

DIY Self-Inspection Checklist

Even if no permit is required, use this checklist before pouring:

Forms:

• ☐ Dimensions match plans
• ☐ Forms are square (diagonals equal)
• ☐ Proper thickness (4" patio, 5-6" driveway)
• ☐ Stakes every 2-4 feet
• ☐ Slope away from structures (1/8" per foot minimum)

Base:

• ☐ Subgrade compacted (footprints don't sink in)
• ☐ Gravel base installed (4" minimum for driveways)
• ☐ No organic material (roots, debris removed)
• ☐ Vapor barrier if needed (enclosed spaces)

Reinforcement:

• ☐ Rebar/mesh elevated on chairs (not on ground)
• ☐ Proper spacing (typically 18-24" for residential)
• ☐ Tied or secured at intersections
• ☐ 2-3" clearance from edges

Ready to pour:

• ☐ Concrete ordered for correct volume
• ☐ Weather forecast checked
• ☐ Tools and help ready
• ☐ Forms braced and double-checked

Frequently Asked Questions

What does a concrete inspector look for?

Inspectors verify forms match permitted dimensions, base is properly prepared and compacted, reinforcement is correctly sized and positioned (not on the ground), drainage slopes away from structures, and setbacks from property lines are maintained. They're ensuring work meets code requirements.

When should I schedule a concrete inspection?

Schedule your pre-pour inspection 24-48 hours before you want to pour. The inspection must happen after forms and rebar are complete but before concrete arrives. Never have concrete delivered until you've passed inspection.

What happens if I fail a concrete inspection?

You fix the issues noted by the inspector, then schedule a re-inspection. Common fixes include repositioning rebar, adjusting forms, or improving base compaction. Re-inspection fees are typically $25-75. You cannot pour until you pass.

Do I need an inspection for a patio?

If you pulled a permit, yes—follow the inspection requirements. If no permit is required in your jurisdiction, there's no official inspection, but using a self-inspection checklist helps ensure quality work. When in doubt, check with your building department.

Key Takeaways

• Pre-pour inspection happens after forms/rebar but before concrete—schedule 24-48 hours ahead
• Common failures: Rebar on ground, forms not square, insufficient base, wrong thickness
• Failing isn't disaster—fix issues and re-schedule
• Have permit and plans on site during inspection
• Use the self-checklist even for non-permitted work

For permit requirements, see do you need a permit. For contractor guidance, see how to hire a concrete contractor. For project planning, visit our complete concrete guide.