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Plumbing

Inspect Water Supply Lines

EASY15 minPlumbingPart of Spring Maintenance

Why It Matters

Burst supply lines are the number one cause of homeowner insurance water damage claims. Replacing them is cheap prevention.

Quick Guide

  1. 1

    Gather your tools and materials

    You'll need: Flashlight. Materials required: necessary materials.

  2. 2

    Perform the inspect water supply lines

    Check flexible supply lines under sinks, behind toilets, and at the washing machine for bulging, cracking, or corrosion.

  3. 3

    Verify and clean up

    Check that the work was completed correctly and clean up your workspace. If replace any supply line that shows bulging or cracking, consider calling a professional.

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Tools & Materials

Tools

  • Flashlight

Community Tips

TipKasa Team

Check supply lines at their connection points to the shutoff valve and fixture first, as 80% of leaks originate from these fittings rather than the line body itself. Tighten any loose compression nuts by hand, then use an adjustable wrench for a quarter-turn only—over-tightening copper or PEX fittings causes the opposite problem.

Tool RecKasa Team

A Ryobi LED Flashlight with magnetic base ($15-25) allows hands-free inspection under sinks and behind toilets, making it easier to spot corrosion, mineral deposits, or pinhole leaks that indicate imminent failure. The magnet secures it to metal pipes, freeing both hands for manipulation or note-taking.

WarningKasa Team

Polybutylene (PB) supply lines installed between 1978 and 1998 become brittle and fail without warning; if gray or white tubing is present, plan for complete replacement rather than patch repairs. Modern PEX lines like those from Uponor ($0.50-1.00 per foot) offer superior durability and should replace any original PB discovered during inspection. ---