A spacer bar (in Dutch: biggenrug, literally “piglet’s back”) is an elongated, arch-shaped support made from concrete, plastic or steel that holds reinforcement mesh at the correct height above the formwork. The name refers to its curved shape, which resembles a piglet’s back. Spacer bars ensure that the specified concrete cover is maintained.
Function
- Maintaining position — the spacer bar holds the reinforcement mesh at the prescribed height above the bottom of the formwork
- Guaranteeing concrete cover — the minimum concrete cover protects the steel against corrosion
- Stability — the reinforcement sits firmly on the spacer bars and does not shift during concrete pouring
Application
Spacer bars are mainly used in:
- Ground-floor slabs — placed on insulation or a membrane, supporting the mesh above
- Foundation slabs — keeping the bottom reinforcement at the correct height
- In-situ concrete floors — when installing reinforcement mesh in cast slabs
Materials and sizes
- Concrete spacer bars — most common, available in heights of 25, 30, 35, 40 and 50 mm
- Plastic spacer bars — lighter, suitable for thin screeds
- Steel spacer bars — for heavier applications with thick reinforcement mesh
Related terms
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