Are Flat Ethernet Cables OK?
You need a cable under a rug or through a barely-open door, and round cable will not fit or lie flat. Flat ethernet cables solve exactly this — thin ribbons that slide where round cables cannot. They work, with tradeoffs worth knowing before you buy, especially versus a proper cable run.
TL;DR / Quick Fix
Quick fix: flat ethernet cables are fine for short runs under rugs and doors — discreet and easy to hide. But they're usually unshielded and flaky over distance, so keep runs short and check the Cat rating. For permanent or long runs, round cable is the safer bet.
Follow these steps
- Know why flat is tempting. Flat cables slide under rugs, through door gaps, and along baseboards nearly invisibly. For a temporary or renter-friendly run, that convenience is real.
- Understand the tradeoff. Flat cables are almost always unshielded (UTP) with tighter-spaced pairs, making them more vulnerable to interference and less reliable over distance than round cable.
- Keep runs short. Under 15–20 meters, a decent flat cable performs fine for gigabit. The problems start on long runs — which is also where the length limits bite.
- Check the real rating. The jacket should print a genuine Cat5e or Cat6 rating. Many listings claim Cat7 or Cat8 on flat cable — treat unprinted claims as fiction.
- Lay it properly. Flat under a rug is fine; folded sharply or pinched under furniture legs is not. Creases damage the pairs just like kinks damage round cable.
- Prefer round for permanent runs. If the cable will live in a wall or under flooring for years, round shielded cable is the grown-up choice — flat is for visible, reversible situations.
What NOT to do
- Do not run flat cable for long permanent installations. Distance plus interference is where flat cable earns its bad reputation.
- Do not believe Cat7/Cat8 flat cable listings. The standards assume round construction — exotic claims on flat cable are marketing.
- Do not pinch it under heavy furniture. A crushed flat cable fails just as dead as a crushed round one.
- Do not use flat cable outdoors. No UV or moisture rating — it will die within a season.
Frequently asked questions
Are flat cables slower?
Not inherently — a good flat Cat6 does gigabit fine. They are less robust over distance, which is different from slower.
Can I paint over a flat cable?
Yes, carefully — flat cables take paint well for camouflage along baseboards. Avoid painting the connectors.
Flat vs round for gaming?
For short runs, identical in practice. Latency differences between decent cables are negligible — pick by installation, not speed.