The wire next time - wiring homes for computer and communications technologies

Sunset, Nov, 1996 by Bill Crosby

Anticipating what wires and cables you'll need as computer and communications technologies evolve

Your remodel is under way, and the crucial walls are opened up. Now is the perfect time to get wired for the information superhighway. But what exactly should you bury in the walls to meet future phone, computer, and Internet needs? "For the foreseeable future, putting in coaxial cable for your TV, and category 5 twisted-pair for your phone should be plenty," says Jim Saucier, engineering manager for T and D Communications, a Mountain View, California, company that specializes in data and communication network installations.

Check to be sure your electrician has had experience with cable installations. To find a cable installer, look in the yellow pages under Telecommunications - Telephone Equipment, Services & Systems, and Telecommunications - Telephone & Television Cable Contractors.

Category 5 cable. It's a lot of wire. Inside the cable are four pairs of wires - each pair twisted together at a different tightness so it doesn't interfere with the others while transmitting data. There are several different levels of cabling, designated categories 2, 3, 4, and 5. (There is no category 1.) Category 4 is no longer used because the difference in bandwidth - the space available for transmitting data - between category 3 and category 4 was not very significant; category 3 is used for voice and low-speed data transmission; and category 2 is for what cabling contractors call "plain old telephone service," or POTS. Category 5 cable is downwardly compatible, which simply means that it can replace lower-capacity cables. So even if all you're going to do is run a basic phone, you can still use one pair of wires in a category 5 cable. Its price varies from about 6 cents to 40 cents per foot (not including installation), depending on the brand of cable and the type of sheathing.

"I'd pull [install] two category 5 cables now; it takes as much labor to pull two as to pull one - just leave them in the wall," Saucier says. His firm recently upgraded the communications wiring in student housing at Stanford University using category 3 wire for voice, category 5 wire for data, and coaxial cable for video.

Coaxial cable. We also recommend installing two coaxial cables along with the category 5 cables; home technology displays we saw at the recent PCBC Western Building Show used paired coaxial cable for the interactive connections of future two-way data transmission links. And wire is cheap.

Saucier is emphatic about installing all wires "home run," which means that each wire you install starts at the same point, usually a panel in your garage or basement. Old phone installations were wired in a "daisy chain," which meant the wire was run from phone to phone rather than back to a central location. "By running everything back home, you can build a little network in your house so you can do things like let computers share a printer, a modem, or whatever the next thing will be," Saucier explains. It also lets televisions share a signal from a cable or satellite.

Fiber-optic cable. Kirk van Druten of San Francisco-based LANSharks Consulting, which also does installations, is skeptical about the need for fiber-optic cable in the home. "Fiber is expensive and troublesome to 'connectorize.' Some folks install it while they have the walls open but leave it 'dark,' with the thought that they could put it to use at some future date," he says. But fiber's primary advantage is transmitting large amounts of data long distances; the short-distance needs encountered at home suggest that fiber will be unnecessary for some time to come. Saucier agrees that fiber is most suitable for commercial applications. His firm used it at Stanford only to link data hubs.

ISDN FOR NOW

The hot new telephone technology, known as ISDN (Integrated Service Digital Network) offers data transmission at speeds almost four times as fast as the fastest conventional modem, and it can still run on telephone wiring. According to Pacific Bell's Mary Hancock, "People have been turning into skeletons waiting for information from the Internet to download. ISDN makes access to the Internet really fast, and allows you to multitask; for example, you can download information while receiving a fax." It may not be available in some areas; call your local phone company for details.

EXPERT'S TIP

Saucier has a trick for future wiring needs: "The best thing you can do is pull a string along with your wire and tie it off at both ends. Make sure you leave an ample pathway. Then, if you need to pull something like fiber-optic later, you're set."