running ethernet through attic

null_pointer_us · 05-12-2006, 07:54 PM

I'm not sure whether this belongs in the electrical forum or the construction forum, but I'm interested in running approximately 50 ft. ethernet cable to my room from a finished bonus room through the attic. I know how to network, so most of my trouble is making sure I don't make the house implode.

:D

Anyway, here's the drill. Upstairs is a bonus room which must have the DSL modem and wired gateway because my dad uses it for VoIP at his desk. To get Internet access down in my room, which is on ground level all the way across the house, I've installed a wireless router in the bonus room and a wireless NIC in my PC. But no matter which hardware I use - and I've tried a lot - I get periodic errors often requiring hard resets of the router and manual configuration - which is annoying. Long story short, I need ethernet run to my room through the attic.

The good news is that there's an unused electrical box and cover up in the bonus room which would be just perfect for an ethernet jack, and that wall just happens to open into the attic which itself just happens to provide a nice walkway over to the top of one of my bedroom walls. Perfect so far, right?

Problem #1

My knowledge of construction is very, very limited, but I do know that the wall is hollow and uninsulated because it's an inside wall. Trouble is, there's a board - a 2x4? - attached horizontally to cover the top of this wall so that I can't simply drop a bunch of cable down into the wall.

There are several holes drilled in this 2x4 for other wires including cable TV and telephone. These wires run right down into the jacks which I want to use for ethernet, so in theory everything should be OK, but, talking to my dad, he seems to think that drilling a new hole through this 2x4 will crack the wall, the plaster ceiling, and who know's what else.

Will I be OK with drilling this hole, or, failing that, is there something I could do to minimize the chance of damage? It's a fairly new house, and the board isn't really near any of the plaster ceiling - maybe 2-3 feet away. If I make a crack in his vaulted, plaster ceiling, he's gonna kill me...

Problem #2

Assuming I can get the cable down into the wall of my room, how will I fish it out? I wish to use an existing box and jack along that wall since my dad doesn't want any new holes cut into his new walls. Surely there's some trick of the trade for this?

Can I cut out part of the plastic electrical box and just use a bent, metal coat hanger to snag the wire and pull it within grabbing range? Or do I risk wrecking some of the other wiring? I'm not sure, but it's possible there's some power cables running through that wall.

And in any case, I can't do this if there's a good chance of ruining something else. Having to call in a professional to open up the wall to fix something I've done to it would really tick my family off...

Advice on this would be much appreciated!

null_pointer_us · 05-14-2006, 04:12 PM

WRT getting cable into an existing electrical box, I found this thread which has some good ideas:

http://groups.google.com/group/misc....5d3c740337868f

I've come up with my own idea using some stuff I have lying around.

Get the following:

A piece of small chain about 6" in length, a width smaller than the width of the cable, and able to be attracted by a magnet
A telescoping magnet, like a pen-shaped pocket magnet.
A flashlight with a good, long charge to it. And maybe some replacement batteries.
A pair of needle-nose pliers that can fit a little ways into the punch-out hole of an electrical box.
Lots and lots of patience, and a helper...with even more patience.

Here's the process:

Remove the cover from the existing electrical box and punch out one of the hole tabs so that the wire can fit through.
Set the flashlight on something that can angle it slightly up (or down) to shine through the punchout hole and into the wall.
Go upstairs and drill two holes in the top board of the wall: one for the cable and one for your eye.
Attach the short length of chain to the end of the cable and begin lowering the cable down one of the two newly drilled holes.
Lower the cable until it reaches the light from the flashlight. Since the wall is fairly dark, the light should be quite visible.
Go downstairs and insert the telescoping magnet through the punchout hole until it attracts the metal chain and clicks onto it.
Carefully pull the telescoping magnet back through the hole, stopping just before the point where the chain presses against the box and forces itself off the magnet.
With your other hand, use the needlenose pliers to grab the chain and thread it into the electrical box.
Discard the flashlight and grab the chain with your free hand, using the pliers to work the end of the cable up slightly and through the punchout hole.

(I still need advice on whether drilling will cause cracks in the wall.)

Teetorbilt · 05-14-2006, 08:15 PM

Tell dad that drilling a 5/16" hole through the top plate for Cat5 will not cause any structural damage. How does he think that all of the rest of the electrical/phone/alarm systems were installed?

null_pointer_us · 05-15-2006, 06:08 PM

Thanks! I plan to tell him after the project's finished, though.