Q: I am building a new home and want to wire it for a future network of two or three personal computers that may use the same printer and other devices. What cabling and structure will take me through the next five years?
A: A house is usually constructed of permanent, closed walls, floors, and ceilings, and is expected to stand for 50 to 100 years. A typical family home contains telephones, televisions with video recorder and cable-TV connections and, maybe, a small local area network. A telecommunications cabling system should provide every room in your house with telephone outlets for telephone and fax, video outlets for video, and even data outlets for an in-home network. Think of a telecommunications cabling system as the fourth utility. You could not build a new home with only one convenience outlet in the kitchen and another in the master bedroom--the placement of these is specified in nfpa-70 of the National Fire Protection Association (Quincy, MA). But new homes are being built today with severely limited telecommunications cabling systems.
I recently visited with an architect for whom I normally consult on commercial projects. He is designing and building seven very high-end homes in an affluent neighborhood in Austin. His first question was, "What do I need to do to ensure that these homes are cabled for every possible telecom service?" My answer was the same as when we are discussing everything from cleanrooms to classrooms: "Make certain that the pathway is properly sized to support growth. If you make a mistake in the number of cables required, or the cable of today does not meet the needs of the years to come, then you can add to or completely change the cable without opening the walls."
Designing a pathway system for your home is very simple. There is no complicated software to learn. Plan sufficient outlet locations to prevent the need for extension cords. Provide an outlet location in each room. Additional outlet locations should be provided within unbroken wall spaces in a room of 12 or more feet.
With a little planning and a Saturday afternoon at the site before the gypsum board is hung, you can install a piece of flexible plastic conduit from each telecommunications outlet box to an area that will remain accessible for the life of the house. Be generous with the number of outlet boxes in each room--you don`t have to put all your cable choices in all the boxes. With the flexible conduit in place, you can add and remove cables as your needs change. Hint: Before the gypsum board goes up, videotape the entire house. Then, if you need to know where the cable runs are, you can simply review the tape.
Installing a residential cabling system is not difficult for the average do-it-yourselfer. Most manufacturers` product lines are designed for snap-together assembly. Do not attempt to mix parts from multiple product lines on the same faceplate. This setup produces a sort of a round-peg-in-the-square-hole scenario.
As a minimum, install one or two Category 5 4-pair unshielded twisted-pair (utp) cables and one or two 75-ohm coaxial cables to each outlet location. Although you don`t need to own these documents, you should know that Category 5 4-pair utp cable is specified in ansi/tia/eia-568a, and 75-ohm coaxial cable is specified in scte ips-sp-001.