Footing & Columns Checklist for any Building 

Footings and columns are the most critical components of any building, as they transfer the entire load of the structure safely to the ground. Even a minor mistake during their casting can be dangerous for the overall structure.

Let's first understand the technical details of the three points you mentioned, followed by a proper, actionable checklist.

1. Detailed Explanation of Key Aspects

A. Verticality (Plumb)

• What is it? Ensuring the column stands perfectly vertical at a 90-degree angle.

• Why is it important? If a column tilts even slightly, the load transfer will be improper, creating "eccentricity." This puts extra stress on the column and significantly increases the risk of structural failure.

• How to check? After erecting the shuttering (formwork), a 'Plumb Bob' is used to check verticality on at least two adjacent faces of the column. For large or tall columns, surveying instruments like a Total Station or Theodolite are used.

B. Reinforcement Spacing

• What is it? The distance between the main vertical steel bars and the binding rings (stirrups/ties).

• Why is it important? If the spacing exceeds the structural drawing's specifications, the column's shear strength will decrease, making it highly vulnerable, especially during earthquakes.

• How to check? Use a measuring tape to verify the center-to-center (C/C) distance between the stirrups. Ensure that the stirrup hooks are bent inward at a 135-degree angle. Additionally, Cover Blocks (usually 50mm for footings, 40mm for columns) must be securely placed between the steel and the formwork to maintain concrete cover and prevent the reinforcement from rusting.

C. Starter Casting

• What is it? Before the main column concreting begins, a small base layer of concrete (about 50mm to 75mm in height) is cast on top of the footing or slab. This is called a starter.

• Why is it important? It acts as a firm base and guide for the main column's shuttering. This ensures the formwork fits in perfect alignment and prevents concrete slurry leakage from the bottom during the main casting.

This list is divided chronologically: Before Concreting, During Concreting, and After Concreting.

Construction Checklist: Footings & Columns

General Project Information (Prior to Inspection)

[ ] Verify that the latest revision of the structural drawings and specifications is being used. 

[ ] Ensure all necessary building permits are obtained and displayed. 

[ ] Confirm that material testing reports (soil bearing capacity, concrete mix design, rebar mill certificates) are approved.

Part 1: Footings (Foundations)

A. Pre-Pour Inspection (Excavation & Formwork)

[ ] Soil Bearing Capacity: Confirm the excavated surface matches the soil type assumed in the structural design (and verified by a geotechnical engineer if required). 

[ ] Subgrade Condition: The base must be compacted, level, undisturbed, and free of loose soil, debris, organic matter, or standing water. 

[ ] Dimensions: Check excavation width, length, and depth against drawings.

[ ] Location & Alignment: Verify the footing centerlines match the building grid lines set by the surveyor. 

[ ] Formwork: Ensure forms are rigid, braced properly to withstand concrete pressure, clean, and coated with form oil (release agent). 

[ ] Moisture: If pouring directly against earth, ensure the soil is slightly damp (not saturated) to prevent it from sucking water from the concrete.

B. Footing Reinforcement (Rebar)

[ ] Size & Grade: Verify bar diameters and steel grade (e.g., Grade 60) match specifications. 

[ ] Placement & Spacing: Check bottom and top bar spacing (both directions). 

[ ] Concrete Cover: Ensure proper use of "chairs" or concrete dobies to maintain the specified clear cover between the rebar and the ground (usually 3 inches/75mm for concrete cast against earth). 

[ ] Cleanliness: Rebar must be free of excessive rust, mud, oil, or paint. 

[ ] Hook Lengths/Bends: Verify that hooks and bends comply with standard codes (e.g., ACI).

C. Column Dowels (Starter Bars)

[ ] Location: Crucial step. Verify that the column rebar cage (starter bars) is located exactly on the centerline and within the footing formwork. 

[ ] Configuration: Check the number of bars, diameter, and shape (e.g., "L" bends at the bottom). 

[ ] Embedment Depth: Ensure the dowels extend into the footing and above the footing surface by the specified development/lap splice length. 

[ ] Securing: The dowels must be securely tied or welded to the footing rebar to prevent movement during the pour.

Part 2: Columns (Structural Supports)

A. Pre-Pour Inspection (Formwork & Alignment)

[ ] Surface Preparation: If casting on previously poured concrete (the footing or a lower slab), ensure the surface is roughened (scabbled) and cleaned to ensure a good bond. 

[ ] Kicker/Starter: If using a concrete starter rib, verify its height and alignment. 

[ ] Verticality (Plumbness): Crucial. Use a plumb bob or transit to check that the forms are perfectly vertical. Check two adjacent faces.

[ ] Dimensions: Verify the cross-sectional size (e.g., 12"x12"). 

[ ] Stability & Bracing: Formwork must be able to withstand high concrete pressures. Check form ties and external bracing. 

[ ] Cleanout Ports: Confirm that "windows" or ports exist at the base to remove debris right before pouring. 

[ ] Form Oil: Ensure internal surfaces are coated.

B. Column Reinforcement (Rebar Cage)

[ ] Vertical Bars: Count the vertical bars and verify their size and location within the column. 

[ ] Lap Splices: Verify the lap length of the column bars protruding from below matches drawings. 

[ ] Ties/Stirrups: Check tie bar size, shape, and spacing. Note special confining zones (closer spacing) near the top and bottom of the column. 

[ ] Tie Hook Angles: Verify that stirrup hooks have a 135-degree bend (seismic hook) when required, rather than just 90 degrees. 

[ ] Concrete Cover: Ensure sufficient side cover using plastic spacers or concrete dobies between the cage and the formwork.

Part 3: During Concreting (Both Footings & Columns)

[ ] Concrete Mix: Verify the delivery ticket matches the specified concrete strength (PSI/MPa), slump, and max aggregate size. 

[ ] Slump & Sampling: Perform slump tests on-site and cast test cylinders/cubes for strength verification. 

[ ] Placement Height: To prevent segregation, concrete should not be dropped freely from a height exceeding 3–5 feet (1–1.5m). Use a tremie or chute for tall columns. 

[ ] Layer Thickness: Place concrete in horizontal layers (usually 12–18 inches thick) for columns. 

[ ] Vibration/Compaction: Ensure mechanical vibrators are used properly. Do not use the vibrator to move concrete horizontally. Insert vertically at close intervals. 

[ ] Cold Joints: Ensure placement is continuous to prevent unintentional cold joints between batches. 

[ ] Cold/Hot Weather: Monitor concrete temperature and apply appropriate measures (e.g., ice water in hot weather, insulation in cold weather).

Part 4: Post-Concreting (Both)

[ ] Formwork Removal: Do not strip forms until the concrete has reached sufficient strength (consult structural engineer for minimum time). 

[ ] Curing: Begin curing immediately after finishing. Options include: water ponding, wet hessian/burlap, or spraying a curing compound. Keep the concrete moist for at least 7 days (depending on cement type and weather). 

[ ] Visual Inspection: Once forms are stripped, inspect for defects: 

* Honeycombing: Voids due to poor vibration. 

* Cold Joints: Visible separation between layers. 

* Cracks: Thermal or shrinkage cracks. 

* Exposed Rebar: Due to low concrete cover.

[ ] Repairs: Major defects must be assessed by the structural engineer and repaired using approved non-shrink grouts or epoxy injection methods. 

[ ] Final Plumb Check: Verify the final columns are still plumb after stripping.

Disclaimer: This checklist is for general guidance. Always refer to specific project structural drawings, architectural specs, local building codes (e.g., IBC, ACI, Eurocode), and safety regulations.