What is the function of chairs or spacers in rebar installation?

• A. Hold color
• B. Speed curing
• C. Maintain cover and alignment
• D. Provide decoration

Answer: (C)

Chairs and spacers are used to position reinforcing bars inside concrete. Their primary job is to keep the bars at the correct distance from the form and from each other, so the concrete cover and the bar alignment match what the engineer designed. This cover protects the steel from moisture, chemicals, and fire exposure, and it helps the bar bond with the surrounding concrete. Spacers also prevent bars from shifting during pouring and vibration, ensuring proper spacing, avoiding congestion, and allowing the concrete to flow and consolidate properly around the reinforcement. In short, they maintain the intended cover and alignment, which is essential for the strength, durability, and durability of the structure. They’re not used for color, curing speed, or decoration.