Structured Wiring in steel framed house

  • Thread starter Deleted member 12930
  • Start date
D

Deleted member 12930

Guest
Hello,

So I just bought my first home, and want to do my own structured wiring. Well, I guess not completely structured, as it's only Cat5 I'll be running, the cable and phone are already taken care of.

I've done this for my parents home, which we built ourselves. That was obviously VERY easy, since I was able to go in before the drywall went up. This new house though is finished.

It has steel framing, which is leaving me a little unsure of the best way to handle this. It's a one story house, with an attic that gives me access to all the interior and exterior walls. I haven't actually gone up into the attic (besides peeking in during the home inspection), but don't foresee any problems with working up there. It's a HUGE attic, probably enough room to fit at least one good sized room up there.

All of the phone / cable hookups are on interior walls. My hope is that I'll be able to run the Cat5 through the same holes as the phone / cable lines. If not though, that means I'll have to drill through the steel. That's fairly easy, I can get grommets for the right size, so I don't cut the cable when pulling the line through. But since I've never worked with steel like this, I was hoping for some tips / tricks from anyone that has.

I also hope to run speaker cable in my living room, so I can get a nice surround sound setup going. For that I'll have to run the cable through an exterior wall, and also mount outlet boxes, which is one area I have no idea how do to with the drywall up.

So... any advice? :)
 
What you find on your exterior wall will depend on the construction technique and materials. It should be a stud wall like the interior walls but with deeper studs (2x6 instead of 2x4 nominal size in inches). The problem, especially if you live in a cold climate area, is that the exterior wall will be filled with insulation. You may or may not be able to be move it aside to pass the wires. If it's blown-in, expand-in-place foam, you are not going to touch it - it forms both the insulation and vapour barrier and shouldn't be messed with; it's more trouble than it's worth. If it's fiberglass or rock wool or similar, you might consider running a plastic conduit down the wall between the fiber and the drywall - your challenge is getting long(ish) bits of conduit into the attic and running it vertically with a very low ceiling above you. If the roof pitch is steep enough and the conduit sufficiently flexible, you have a chance. Conduit will make future wire pulls relatively easy, so upgrades are less painful.

If there's a lot of insulation, there would likely be a vapour barrier on the inside - you can punch your way through that, but you should re-seal it around the wiring box. It's possible that you can have a 2x6 exterior and another interior stud wall - in some, relatively uncommon circumstances, you can have a 2x2 wall supporting the drywall. This creates a gap between the drywall and the 2x6+vapour barrier+insulation. However, its not uncommon for them to set the interior stud horizontally in this case, which makes snaking wire a pain. I'll bet you won't have this.

Can you access any room from the basement? If you have a suspended ceiling in the basement, you could move a few panels and run wires inside.

Another possibility is to run plenum grade Cat5e inside air conditioning/heating ducts. That can be a way around digging through the walls, but you'll have to confirm it satisfies local building codes.
 
No basement in my house, only an attic. I live in the central valley of California, so no cold weather for me (relatively speaking). The insulation used that I've seen was white and fluffy, looked like it was sprayed on. This was in the attic though, above the ceiling basically. So I don't know if that's going to be different than what's in the walls. All my air conditioning and heating ducts end in the ceiling, so it would be a huge hassle to run wire through them. I'd have better luck with just drilling a hole right through the ceiling and letting the cord hang down (something I obviously won't be doing).

I guess the only real way to find out what is up is to just kind of dive in.

Edit: Oh and thanks for the advice! :)
 
That white fluffy stuff is likely a cellulose insulation or something similar. It can be blown in or dumped from big bags and spread out. It's pretty safe stuff, but just to be safe, you might want to wear gloves (latex, vinyl or nitrile for a sense of touch or tight woven fabric) and a dust mask when digging through it. It's commonly used in attics and mice, squirrels and such like to use it for nests - if you see any holes in the attic, make sure they're sealed or, if deliberate, covered with wire mesh to keep the little buggers out.

It is less likely to be used in walls, since it tends to settle easily. If there's only a thin layer of insulation in the attic (like 6" or less) then I'd not be surprised to see no insulation in the walls, especially if the house dates back to the '60s or earlier. However, steel studs didn't become popular till the '70s. More insulation will cut your air conditioning costs.

If there's no basement, is it a crawl space or slab-on-grade? If the former and you don't mind working on your back in dirt, that is a possibility. I'd select outdoor grade Cat5E in that case for its damp resistance.

If you put the cabling on top of the joists and insulation in the attic, you might consider outdoor grade Cat5e - it has better temperature handling (well a bit IIRC) and around here, indoor and outdoor grades at HD are the same price. The UV resistance of the outdoor grade will be of little significance unless there are openings, such as air vents on gables, that allow a good amount of sunlight in. If it's under the insulation, no worries. Not a big deal but for the same price...
 
If memory serves correctly the blown in insulation get's part of its R-Value by trapping air between the pieces. The general rule is that once it's blown in you don't want to disturb it, as you step on it the air is compressed out and the insulation looses it's effectiveness. More a heads up than anything but I'm an IT guy and by no means an insulation expert so it may be complete BS!
 
Thanks for the advice you two! It's greatly appreciated.

The house was built in 2003, and the foundation is a slab. Either this weekend or sometime this week I'm going to get up there and start digging around in the attic to figure out my plan of attack. I'm really hoping I can run the cable in with the phone line real easily.
 
just run more wire then you need also, when you do a single drop of cat5, run a 2nd or a 3rd just for future use.
 
If you step on the insulation, you'll end up with your feet showing inside the house - the insulation rests on the ceiling drywall and the drywall will not support your weight. You should only walk on the joists. It's not a bad idea to take a decent sized board with you to span across several joists to provide a surface to stand/sit on.
 
yub, my father used to take me on jobs all the time when I was younger. He works in HVAC, so I'm used to either crawling underneath houses, or navigating around in attics. Needless to say, I'm used to a lot of different construction environments. I've just never done structured wiring in a house that's already built.
 
be careful with that stuff, be sure to wear a mask rated to protect against this insulation, i ran a single wire in an attic similar to this and coughed for a week... it definitely isn't healthy.
 
So I still have not run the cable. I tried the other weekend and hit a really shitty snag. I am half tempted to pay someone to do it for me, but know that will get really expensive.

So my plan is to start with drilling the hole in the top of the stud, than dropping in the fishing rod down to the outlet box.

My problem is that once I do that, how in the hell do I retrieve the fishing rod so I can actually attach and than pull the cable through?!? Do I actually have to open up my whole wall to gain access? Or is there any unobtrusive way of doing this?
 
NickTheNut said:
So I still have not run the cable. I tried the other weekend and hit a really shitty snag. I am half tempted to pay someone to do it for me, but know that will get really expensive.

So my plan is to start with drilling the hole in the top of the stud, than dropping in the fishing rod down to the outlet box.

My problem is that once I do that, how in the hell do I retrieve the fishing rod so I can actually attach and than pull the cable through?!? Do I actually have to open up my whole wall to gain access? Or is there any unobtrusive way of doing this?
Click to expand...
I'm confused on how you are trying to do it??? If you are using a rod (not a tape) then you should make sure it's long enough to reach the hole without being dropped in. Or if it's a flexible rod, you can drop it in and pull it out the hole without doing damage. You won't be able to use an existing outlet box unless it's a low voltage box without the back, so I hope you're not trying to get it through an existing box. I think I'm mostly confused because dropping lines is so simple, how could you be stumped??? :confused:

EDIT: I just refreshed and saw you were trying to get it through an existing box. Go buy some remodel boxes or some low voltage boxes and put in some new boxes for your data.
 
supergper said:
I'm confused on how you are trying to do it??? If you are using a rod (not a tape) then you should make sure it's long enough to reach the hole without being dropped in. Or if it's a flexible rod, you can drop it in and pull it out the hole without doing damage. You won't be able to use an existing outlet box unless it's a low voltage box without the back, so I hope you're not trying to get it through an existing box. I think I'm mostly confused because dropping lines is so simple, how could you be stumped??? :confused:

EDIT: I just refreshed and saw you were trying to get it through an existing box. Go buy some remodel boxes or some low voltage boxes and put in some new boxes for your data.
Click to expand...

Sorry it's not a rod - it's tape.

And holy crap I had no idea about remodel boxes! I was so discouraged by the prospect of opening up my wall to put in a simple outlet box!
 
I used fish tape when helping my dad run Cat5 from the basement, up the clothes chute to the attic, then down into the upstairs office.

It can be difficult, especially maneuvering it through insulated walls, but it's easier than a non-flexible rod.
 
You must log in or register to reply here.
Back
Top