For 15mm plastic pipework, what are the maximum horizontal and vertical clipping distances?

• A. 300 mm horizontally and 500 mm vertically
• B. 250 mm horizontally and 450 mm vertically
• C. 350 mm horizontally and 550 mm vertically
• D. 400 mm horizontally and 600 mm vertically

Answer: (A)

Clipping distances set how far apart supports are placed to keep pipework stable, aligned, and free from unwanted movement or noise. For 15 mm plastic pipework, the recommended maximum horizontal spacing is 300 mm and the maximum vertical spacing is 500 mm. The tighter horizontal spacing helps prevent sagging and misalignment along wall runs, where horizontal support is most critical. The vertical spacing can be a bit larger because gravity pulls the pipe downward, but it still needs regular support to stop movement and vibration, so 500 mm provides a practical balance. If you used closer spacing, installation would be more time-consuming; if you allowed greater spacing, the pipe could bow, rattle, or shift over time. In practice, always adapt to the specific installation conditions, but these are the typical maximums for 15 mm plastic pipe.