What is the minimum number of 1-hole straps needed to fasten 39' of 12-2 MC cable to a wall?

To determine the minimum number of 1-hole straps needed to fasten 39 feet of 12-2 armored cable (MC cable) to a wall, one must understand the electrical code requirements for securing cables. According to the National Electrical Code (NEC), cables must typically be secured at certain intervals to ensure safety and compliance.

For non-metallic sheathed cable like 12-2 MC, the NEC requires that cables be secured within 12 inches of any box or fitting and thereafter at intervals not exceeding 4.5 feet (54 inches) along the run. To calculate the number of straps required, first consider the total length of the cable: 39 feet.

1. Attach a strap within 12 inches of the beginning of the run.

2. Then, divide the remaining length (post-initial strap) into sections where each section can be controlled by the 4.5-foot rule.

39 feet can be divided as follows:

• The first strap is placed within 12 inches (1 foot), which leaves 38 feet remaining.

• The remaining length needs to be secured at intervals no greater than 4.5 feet.

You'll secure the cable at 4.5-foot intervals along the remaining