Civil Casting: a Kicker is Necessary or Not?

 

Here’s your civil casting kicker illustration—it shows exactly how the small concrete step (50–75 mm high) is formed at the base of a wall or column during the foundation pour.

The diagram highlights:

• Foundation slab with rebar protruding.

• Kicker cast on top of the slab, acting as a guide.

• Formwork is fixed to the kicker to ensure alignment.

• Wall concrete poured above, with the kicker preventing leakage at the joint.

What a Kicker Does in Civil Casting

A kicker is a small concrete projection (usually 50–75 mm high) cast at the base of a wall or column during the foundation pour. It acts as a guide and seal for the next vertical concrete pour.

Why It’s Necessary

• Alignment control: Ensures the wall or column formwork is correctly positioned.
• Leak prevention: Stops slurry leakage at the joint between the slab and wall.
• Structural continuity: Provides a clean, roughened interface for bonding between pours.
• Ease of formwork fixing: Simplifies vertical shuttering alignment.

When It Might Be Omitted

• For precast walls or waterproof joint systems, where alignment and sealing are handled differently.
• In temporary or non-load-bearing structures, where precision isn’t critical.

So, in civil casting, a kicker is recommended and generally necessary for structural accuracy and watertightness—especially in basement walls, retaining walls, and water tanks.

Diagram of Kicker Placement in Civil Casting

Here’s a clear step-by-step guide showing how a kicker is placed in civil casting. This will help visualize its role in ensuring alignment, watertightness, and structural continuity at the base of walls or columns.

1. Prepare Foundation Slab

Ensure the slab surface is clean and ready for kicker placement.

• Remove debris and laitance from the slab surface

• Roughen the surface for better bonding

• Mark the wall or column layout lines

2. Cast the Kicker

Critical

Pour a small concrete upstand (50–75 mm high) along the wall or column line.

• Use the same grade of concrete as the slab

• Maintain uniform height (50–75 mm)

• Ensure kicker width matches wall thickness

3. Fix Formwork Against Kicker

Alignment

Position vertical shuttering against the kicker for accurate alignment.

• Place plywood or steel formwork flush with the kicker edge

• Secure with props and ties

• Check the plumbing and line before tightening

4. Pour Vertical Wall Concrete

Final Pour

Proceed with wall or column casting using the kicker as a guide and seal.

• Pour concrete continuously to avoid cold joints

• Vibrate properly for compaction

• Ensure the slurry does not leak at the base joint