Network Building: Network Installation Guidelines

The hardest part about installing network cable is the physical task of pulling the cable through ceilings, walls, and floors. This job is just tricky enough that you shouldn’t attempt it yourself except for small offices. For large jobs, hire a professional cable installer. You may even want to hire a professional for small jobs if the ceiling and wall spaces are difficult to access.

Here are some general pointers to keep in mind if you decide to install cable yourself:

  • You can purchase twisted-pair cable in prefabricated lengths, such as 50 feet, 75 feet, or 100 feet. You can also special-order prefabricated cables in any length you need. However, attaching connectors to bulk cable isn’t that difficult. You should use prefabricated cables only for very small networks and only when you don’t need to route the cable through walls or ceilings.

  • Always use a bit more cable than you need, especially if you’re running cable through walls. For example, when you run a cable up a wall, leave a few feet of slack in the ceiling above the wall. That way, you’ll have plenty of cable if you need to make a repair later on.

  • When running cable, avoid sources of interference, such as fluorescent lights, big motors, X-ray machines, and so on. The most common source of interference for cables that are run behind fake ceiling panels are fluorescent lights; be sure to give light fixtures a wide berth as you run your cable. Three feet should do it.

  • The maximum allowable cable length between the hub and the computer is 100 meters (about 328 feet).

  • If you must run cable across the floor where people walk, cover the cable so that no one trips over it. Inexpensive cable protectors are available at most hardware stores.

  • When running cables through walls, label each cable at both ends. Most electrical supply stores carry pads of cable labels that are perfect for the job. These pads contain 50 sheets or so of precut labels with letters and numbers. They look much more professional than wrapping a loop of masking tape around the cable and writing on the tape with a marker.

    Or, if you want to scrimp, you can just buy a permanent marker and write directly on the cable.

  • When several cables come together, tie them with plastic cable ties. Avoid masking tape if you can; the tape doesn’t last, but the sticky glue stuff does. It’s a mess a year later. Cable ties are available at electrical supply stores.

  • When you run cable above suspended ceiling panels, use cable ties, hooks, or clamps to secure the cable to the actual ceiling or to the metal frame that supports the ceiling tiles. Don’t just lay the cable on top of the tiles.