NASCLA General Contractor Practice Exam 2026 - Free Practice Questions and Study Guide

Rebar should be installed before pouring concrete to achieve optimal results in a concrete mix. This timing allows the rebar to be properly embedded within the concrete, enhancing the structural integrity of the final product. When rebar is placed prior to the concrete pour, it can effectively help to manage tensile stresses that the concrete alone cannot withstand since concrete is strong in compression but weak in tension.

If rebar were installed after the concrete has cured, it would not provide the necessary support within the concrete matrix, as it would not be able to bond with the cured concrete effectively. Installing it during the mixing process would also be ineffective since the rebar needs to be placed in specific positions to optimize load distribution and would not achieve adequate bonding in a mixed state. Placing rebar immediately after setting concrete would be too late for it to serve its intended purpose since the concrete would have already begun to harden, impeding effective integration and reducing the overall strength and resilience of the structure.

Therefore, the correct approach is to place the rebar before pouring the concrete to allow for the optimal interaction between the rebar and the concrete as it cures.