Rebar & Reinforcement Inspection

Rebar size and spacing must match structural drawings. Common residential sizes: #4 (1/2") and #5 (5/8"). Spacing typically 12" or 16" on center.

1. Check bar size matches plans — measure diameter (#4 = 1/2", #5 = 5/8", #6 = 3/4")

2. Measure spacing between bars — should match plans (typically 12" or 16" OC)

3. Verify bars in both directions for slabs and walls (grid pattern)

4. Check for proper bar placement — bottom bars in slabs, both faces in walls

5. Verify any special reinforcement at corners, openings, and load points

6. Look for bar mark tags or labels to confirm correct grade (Grade 60 is standard)

- Wrong bar size (undersized rebar = under-strength concrete)

- Spacing too wide (concrete between bars not reinforced)

- Missing bars in one direction

- Wrong bar placement (top vs bottom of slab)

- Grade 40 rebar used instead of Grade 60

- Rebar not in both faces of thick walls

Minimum concrete cover protects rebar from corrosion. Chairs and supports keep rebar at proper position during concrete pour. Cover: 3" for soil contact, 40mm for bars up to 20mm diameter (50mm for larger bars).

1. Check chairs/supports are holding rebar at correct height in forms

2. Verify cover to soil — minimum 3" clear for concrete cast against earth

3. Verify cover for formed surfaces — minimum 40mm for bars up to 20mm diameter, 50mm for larger bars in walls, 3/4" for slabs not exposed to weather

4. Check that chairs are spaced close enough to prevent rebar sagging (4-5 feet maximum)

5. Verify chairs are made of approved material (plastic, concrete, or coated wire — not bare metal)

6. Check that rebar is not resting on the ground or on forms without chairs

7. Walk along the rebar — it should not deflect significantly when stepped on

- Rebar sitting on ground without chairs (no concrete cover underneath)

- Insufficient cover — rebar too close to surface (will corrode and crack concrete)

- Chairs spaced too far apart — rebar sags between supports

- Rebar pushed down during concrete pour (workers walking on it)

- Bare metal chairs that can rust and stain concrete surface

- Chairs sinking into soft subgrade

Where rebar must be joined, lap splices must overlap by the required development length. A practical rule of thumb is 40 bar diameters minimum. Splices must be tied with wire.

1. Check lap splice length — minimum 40 times bar diameter (#4 = 20", #5 = 25", #6 = 30") for standard cases (this is an approximation — actual requirements per ACI 318 depend on bar size, concrete strength, and cover)

2. Verify splices are staggered — not all bars spliced at the same location

3. Check that spliced bars overlap side by side (not end to end)

4. Verify all intersections and splices are tied with tie wire (every other intersection minimum)

5. Check for mechanical splices or welded connections if specified in plans

6. Verify continuity of rebar through footings, walls, and slabs where required

7. Check dowel bars connecting footings to walls (proper length, spacing, and position)

- Lap splice too short (joint is weak point)

- All splices at same location (creates weak plane)

- Bars butted end-to-end instead of overlapped

- Untied intersections (bars shift during pour)

- Missing dowels between footing and wall

- Wrong splice location (should be in low-stress zones)