The Problem Of Unused Cabling

Makarand writes "Technological advances constantly render functional cable obsolete by demanding data transfers at higher rates which older cabling cannot support. New cables that support higher data rates are laid right over older wires. The old wires are simply left in place and abandoned. This interesting article talks about the problems caused by abandoned cabling. According to an estimate several billion feet of abandoned cable lies unused in the plenum spaces of buildings that allow air to circulate creating a fire hazard. Also, very few firms currently worry about removing cabling when they move out of a building."

Comments

Some Thoughts from an Expert...

[lonb]

I used to run an ISP that was owned by a real estate firm. We wired many buildings in NYC and provided additional services, such as wiring tenant offices and providing Internet access. There are several considerations not pointed out here:

A. Limitation of Knowledge. The guys who do a lot of the wiring work don't know what the cables do -- believe it or not. My two most experienced, and best, pullers couldn't tell you what ethernet was if their life depended on it. Heck, I had one guy who didn't know what T568b was, but could punch down Cat5 to a T568b block in five seconds flat. All they knew was what they were told to install.

In the past I had specifically had discussions with them about pulling cables out. Unless they are explicitly directed by the landlord of the building (who knows even LESS than they do) they will not, and probably should not, touch cables that are pre-existing. This is due to fear of not knowing what they could be doing, and worse, what they are, or aren't, doing.

B. Cross-office runs. In one of my buildings, for example, each floor was an average of 12,500 feet. The average office was 800 sq. ft. Most floors had upwards of 10-12 offices on them. In order to get riser pulls (cabling run in the central, vertical risers of the building) to office drops (termination points for those cables), these typically ran over the other offices. It was typical for the first office, closest to the riser) to have anywhere from 20-40 cables running through their plenum cores that had nothing to do with that office.

Imagine you come in Monday morning, after a neighbor moved in that weekend, to find all your cabling (data, phone, cable TV, leased lines) had be removed by the overly eager data people.

C. Simple CBA. The bottomline for any real estate firm is, well, the bottomline. The risk of fire due to overly full cabling space is fairly minimal compared to the risk of losing money and facing lawsuits -- or worse, losing tenants.

The cost of pulling existing cabling plus the risk of damaging infrastructure minus the value of open space is just not in the favor of making the change. It's really that simple.

When all is said and done, with my engineering cap on, I'd like to see thorough documentation on cables and better diagrams of floors showing what cable goes where -- and it's really not that hard. But try telling a rushing tenant that they have to wait two weeks while your engineering team documents cables, yeah right.

Also, with my engineering cap on, I'd make one suggestion for anyone moving into a new office. If you are going to pull out the old cables, and it is in roughly strong strength, use it to snake your new cables! That's what we often did. There are a few snares with this trick to watch out for, but if you have good pullers they'll know what to do -- if you give them the green light.