Many landlords require low voltage cabling such as Ethernet inside the wall cavity or floor channel to be run in conduit. When planning cable runs, consult with your IT department and cabling contractor to determine the number of wires that will be run to each destination. Be certain the architect is aware of the number of cables so the plans reflect the proper sized conduit.
In a typical office environment, we generally recommend a minimum of three (3) cables per destination (1-phone, 1-computer, 1-peripheral). Although some VoIP telephones accept direct computer connection freeing up a cable, the additional wire can still be used for a peripheral or spare/backup. It costs less to run the cable during construction than installing cable once the walls and ceilings are closed up.
Ensure the architect specifies a note indicating conduit should have a drag line allowing for easy cable pulls for your cabling contractor.
Recommended conduit sizing for Cat6 cables are:
(3) Cables – 1/2″ Conduit
(5) Cables – 3/4″ Conduit
(8) Cables – 1″ Conduit
(14) Cables – 1- 1/4″ Conduit
(19) Cables – 1- 1/2″ Conduit
(32) Cables – 2″ Conduit
Use this as a sizing guide for other types of cable such as VGA, HDMI and audio.
2024 UPDATE: Revised with Fiber Calculations: Click to read updated post
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A lot of cat6 has a spine in it. The cat6 you mentioned in your conduit sizing. Does the wire have a spine or not.
Hi, at the time the article was written, there was no pair separator spine. Just the twisted pairs. Thanks for adding that clarification.