Common Faucet Installation Mistakes
Updated February 20, 2026
We've seen every faucet installation mistake in the book, and most are completely avoidable. The frustrating part is a botched install usually works fine for the first week -- then the slow drip starts, or the handle loosens, or a supply line lets go while you're at work. Here are the mistakes we see most often.
Overview
We've seen every faucet installation mistake in the book, and most are completely avoidable. The frustrating part is a botched install usually works fine for the first week -- then the slow drip starts, or the handle loosens, or a supply line lets go while you're at work. Here are the mistakes we see most often.
What to Know
Pro Tips
- Photo your sink from below before shopping -- show it to the plumbing associate if unsure.
- Always have a basin wrench. $15, essential.
- Flush lines 30 seconds before installing the aerator to clear debris.
Mistakes to Avoid
- Wrong faucet for your sink hole configuration.
- Overtightening until something cracks.
- Not checking shutoff valves while access is easy.
- Skipping the paper towel leak test.
- Mismatched supply line lengths.
Bottom Line
Most faucet problems come down to measuring wrong or tightening too much. Take your time on prep, match faucet to sink, and do the paper towel test.