How many 1-hole straps are needed to secure 128' of EMT to a wall?

To determine the number of 1-hole straps needed to secure 128 feet of EMT (Electrical Metallic Tubing) to a wall, it's essential to understand the National Electrical Code (NEC) requirements regarding the support of conduit.

According to NEC guidelines, EMT must be securely anchored to the wall at specific intervals. For EMT, the general rule is that it should be supported every 10 feet. Additionally, any offsets, junction boxes, or changes in direction typically require additional supports.

To calculate the number of straps needed for 128 feet of EMT, divide the total length by the maximum spacing allowed for securement. In this case, with a maximum spacing of 10 feet, you would divide 128 by 10, which gives you 12.8. Since you cannot have a fraction of a strap, this means you round up to the next whole number, resulting in 13 supports to cover the entire run of conduit.

However, since you also need to account for support at both ends of the conduit run, you would add an additional strap, making the total 14 straps.

This comprehensive consideration of both the spacing requirements and the necessary end supports clarifies why 14 straps is the correct answer for securing 128 feet of