there's no direct access through wall space from attic to the first floor or basement.  There are wood blocks in the way to prevent a fire from racing from basement to attic.  There are going to be places where the electrician will have drilled through to run wires from the basement to the attack and you may be able to run a wife up through there.  Usually they drill a slightly larger hole than they need.  So bottom floor through the basement and then run a line up to the attic and then do the top floor from the attic.  You can run the wires outsid the building, that's how the cable companies do it to save on labor.  It just doesn't look nice.




---------------
Technician - "We can't even get decent physical health care. Mental health is like witchcraft here."

Drop the wires down or next to your heating and cooling plenum to get from basement to second floor.  It's not code, but then again we are talking about Cat 5 here, not really gonna cause a fire.




"So I will be hitting the snatch hard, I think, tonight." - gzt

Powerline ethernet? Devolo make some pretty good gear for that.
Or do you have some unusual requirements?
--
dmg - HuSi's most dimwitted overprivileged user.

If you don't want to run it outside.

Is the basement finished? Is the attic finished? What kind of insulation in the attic?

Running wires outside will look terrible.

If it looks like a beam above the wall it might indeed be a load-bearing beam that will be no fun to drill through and probably shouldn't be messed with.

If you haven't done this before you're going to have a helluva time making a neat job of it.

I've done a lot of ethernet wiring. I wired my basement office, but when I bought a media player box for the TV and it's wireless connection turned out to be quick enough to play movies, I decided not to bother running a wire to it and stuck with wireless.

The first question is the extent to which you want the wiring done. While living in Ohio, it was pretty easy to run a cat-5 and coax from one spot on the second floor to one spot on the first floor so that both floors could share cable and Internet. But if you want connections in more than one room, that may or may not be easy.

The second question is the design of your specific home. I've lived in houses where running cable through the wall up through multiple floors into the attic was easy. But those were all older homes built back in the 1930s, 1920s, or earlier. More modern homes may have the sorts of things that jimgon brings up that prevent running a wire straight up through the wall.

In other words, this may be a piece of cake and it may be a nightmare. It all depends on what you want to do and what it looks like in the walls of the house you're doing this to.

One clever solution I've seen is to run 4" conduit through out the house with easy access junctions at strategic places. The husband of an aunt of mine did this so that he could wire or rewire at ease in the future. But whether that is feasible or not depends on a large number of factors.

---

There is no more degenerate kind of state than that in which the richest are supposed to be the best.
Cicero, The Republic

First decide where your router will be going.  We'll assume you have a cable/phone drop there already for the modem.  From that space you need to figure out how to get wires to each room you need a drop.  Likely the easiest method is to pull wire from below and above the living spaces.  I wired every room in my house 30 years post construction.  The second floor rooms have jacks that run into the attic then over to a space where two closets stack on top of each other (1st and 2nd floor).  Wires run from each 2nd floor room, into the attic, over to this closet, down into a corner of the closet, through the interior space of the closet, through the floor into the 1st floor closet and down into the basement.  In the basement each drop runs to the wiring closet in the basement where the modem and router is.  Drops on the first floor run from the wiring closet along the basement ceiling to just underneath each wall where I want the jack and then up into the wall space.

Each place where I have a jack was cut into the drywall I used a standard low voltage box designed to be installed after drywall is up.  It has little ears that fold out so it can be slid into a precise hole in the drywall then tightened up to it.  A fishtape (semi rigid wire designed for pulling cable through closed in spaces) was used to run wire from the basement/attic to each hole in the drywall.  You will need a drill with a bit long enough to go through the wall's floor/top plate, the stringer depth plus a few inches to spare.  They make flexible bits for just this purpose but you can usually get away with a spade bit and extension if you have good access.

Depending on your needs you may be able to make use of an existing wire run to pull your cat5.  If you only want to pull one cable from the basement to the attic you might be able to run the fish tape inside the plumping wall alongside the stack pipe.  There might be a cable tv drop you can run the fish tape along, or possibly the wire for your thermostat to furnace.  I ran too many cables to do that so I used the stacked closets and cut a 1" diameter hole in the floor and ceiling of each in order to run multiple cat5, rg6 and cat3 cables from basement to attic.  Then I used fire rated spray foam to close the holes back up.

The problem around doing it right is trying to run wire from floor to floor through a wall, in order to properly hide it you need to open up drywall on the first floor near the ceiling and on the 2nd floor near the floor so you can drill between the floor (through a top plate, ceiling, stringer bay, floor, and floor plate which can add up to 18" or so).  Then you can do the same to the basement and attic and have totally hidden wire runs.  It's much easier to make use of the corner of two stacked closets.

If you do cabling, plan for its replacement, perhaps by creating conduits so you can take the old wiring out and put new wiring in.

Also I found it a wise decision to have 4 port Ethernet sockets instead of just a single one per room; now that everything seems to want to hook up to the Net, including satellite TV boxes and TVs themselves, this was a good idea. I have a Gigabit Ethernet switch in the attic, also connected to a wireless router for mobile phones and those devices which don't have network ports

---

Girls come and go but a mortgage is for 25 years -- JtL

do you use your phone jacks? My wife had her (now our) house built 5 years ago, before I was in the picture, and also didn't specify networking. We rely exclusively on our mobiles and don't have phone service to the house, getting our Internet service via the cable TV provider. When the need arose for wired networking, it turns out the builders had used CAT5 for the phone wiring, and all I had to do was change the wall jacks and stick a patch panel in where the phone drops had been tied together and voila - networking in every room. Strictly speaking, they may not have pulled the phone cabling to the same standards as a data installation, but we're not seeing any problems yet.