Maximum vertical spacing for steel pipe is ___________.

• A. 5 feet
• B. 10 feet
• C. 15 feet
• D. 20 feet

Answer: (C)

The main idea is how far apart pipe supports should be to keep a steel run from sagging and moving. For typical HVAC steel piping, spacing hangers or supports up to about 15 feet apart keeps deflection under control, so the pipe stays aligned, joints stay stressed less, and vibration and leaks are less likely. The 15-foot limit reflects a balance between material weight, thermal expansion, and practical installation tolerances. If you’re dealing with larger temperatures, heavier pipe, or different diameters, closer spacing might be necessary, but 15 feet is the standard maximum for many steel piping installations.