Electrical (non-LV) wiring raceways and hooks

Ira

Active Member
New home construction 50 miles south of Houston, "high voltage" (120/240VAC) rough-in starts in about a month. The house has a closed/unvented/insulated crawlspace over a slab foundation (which is very unusual in this area), so it's kinda like having a basement with a 3' ceiling height. The slab floor is about 18" above natural ground. Plumbing and electrical will go in the crawlspace, but HVAC will go in the conditioned attic. All floor joists are I-joists, and they all run in the same direction.
 
I want all of the wiring to be organized. There are a lot of LV cable management systems (trays, raceways, hooks, etc., which I plan to use, but I haven't been able to find anything for electrical wiring. All electrical wiring will be romex (12ga or larger). No armored shielding, no conduits. I would like to have four or five strategically placed "open top" troughs/raceways for home runs to the load center that will run perpendicular to the I-joists and hang from the bottom of the I-joists. When the wire for a circuit gets to the joist space that contains the first box on a circuit, the wire will come out of the raceway and run parallel with the joists until it gets beneath the wall that contains the box. I would like to use j-hooks screwed to the I-joist webbing for the runs that are parallel to the joists, and use the pre-punched knockouts in the webbing when going from box to box on a circuit on a wall that is perpendicular to the joists.
 
I know there are a lot of options for doing the above for LV wiring (which I plan on doing), but I haven't found any that specifically say they can be used for residential electrical wiring (non-LV). Does this stuff exist for non-LV residential wiring? Links appreciated.
 
Thanks,
Ira
 

wkearney99

Senior Member
Slab over crawl-space?  I mean, there's slab right on grade, and there's pier and beam, but a slab on a pier and beam?
 

Ira

Active Member
I said "crawlspace over a slab foundation", not vice versa. There's a regular slab on grade. The first/only floor is 4' (finished level) above the top of the slab with the floor I-joists supported by a continuous CMU block perimeter stem wall and 3' tall pony walls sitting on the slab.
 

wkearney99

Senior Member
Ah, right.  

There's a lot of different kinds of wireway products, and you're asking can those be used in a residential install for AC line voltage?  It's not commonly done, I'd gather mainly due to the considerable added costs for materials and labor to install it. Raceway is a LOT more expensive than stapling romex to wood. It's one thing to plan for all kinds of clever stuff, it's another thing to not break the budget under the weight of all the added little costs.

That and there are electrical issues with de-rating how many cables can be in closer proximity in the gutters.  But I'm no electrician, what does yours says about the idea?

You'd also do well to find out how your local electrical inspectors treat such installations, because what can be done often runs afoul of what will successfully pass inspection.
 

Ira

Active Member
The house is outside the city limits, and the county/state don't do electrical inspections (or a lot of other new construction inspections done by cities). Haven't discussed with electrician because I doubt that he's ever used troughs and J-hooks. This isn't done around here (all new construction wiring is almost always in the attic because the houses almost never have a crawlspace), so I want to know what is available before talking to him.
 
I found Cableway troughs from Arlington...
 
http://www.aifittings.com/catalog/non-metallic-cable-fittings-and-supports/cableway-cable-runway-support-system/T23T
 
...that I think will work. Approved for power cables. Looks like the trough, brackets, etc., will run about $10/foot combined, so the total cost for this stuff should be under $2K for my house. Arlington's spec's say that fill limit is 26 for 12/2 romex, That should be enough for me since I have a main panel and a subpanel (one on each "end" of the house), and they will use different troughs. Several of the circuits closest to the panels won't be run in the troughs. Also, some of the heavier cable, e.g., HVAC will probably not be put in the troughs.
 
The J-hooks I would like to use for electrical and LV cables are from Platinum Tools, and cost no more than $3 each. Since I will only use them when running parallel to the I-joists, I'm guessing  maybe 200 J-hooks at most.
 
If the above is correct (and I can use the J-hooks), it will add about $2500 to the cost. Not cheap, but I think it is worth it.
 

wkearney99

Senior Member
Don't do vs still a good idea to follow code.  I've had dialogs with a bunch of people over the decades that seem to take pride in cobbling together whatever they want, code-be-damned. Two have had electrical fires, one directly the result of just making it up as he went along. Fortunately neither led to significant property loss.

Following code is even more valuable if the local sparky isn't going to know de-rating and such unless they're doing this sort of work all the time.  Could be, but I'd be surprised.

I get why LV in wireways and such is tempting, as adding more CAT/whatever, fiber or who knows what at a later point would certainly be convenient if there's something fancy like a hinged-lid wireway ready for use.

I'm unclear on how AC wiring in troughs is necessary for a residence, especially down in a crawlspace.  Using romex mechanically fastened to frame is a known cost quantity, easily done and largely free from issues.   That and it's not like the AC circuits are going to change in a residence.  For commercial spaces, where there's potential for complete turnover from one tenant to the next, sure.  But a house?

Up front costs, a bit here, a little bit there... doesn't seem like much.  But when you start tallying it up against the ton of other little things... eventually budgets come into play.  
 
I'm not saying don't do it, I'm just wondering why bother for AC wiring?  
 

Ira

Active Member
I guess you can chalk it up to OCD. I'm not ignoring code. That's why I'm asking the questions... so I can be better informed. I think Cableway will fit my needs based on the documented fill limits, so there shouldn't be any de-rating.
 
I doubt many people will recoup the cost of using cable management systems in homes (attics, basements, crawlspaces, etc.) by making future enhancements. It's not that much harder to run new cable thru existing holes, staple it, etc., and most of that cable is also in an attic or crawlspace. However, people still do it, I guess for pride of ownership (like me in my previous home). My guess is most people who use expensive cable management systems and techniques in homes are DIY'ers that are willing to tackle the job, but can't/won't DIY for electrical wiring and won't pay the upcharge to have the electrician do it.
 
I've seen pictures of residential wiring where people must have paid a fortune to have all of the wiring (including the romex) "combed". To me, that's going too far. I'm simply trying to find a middle ground where I would be happy with the outcome in relation to the cost. Most of us would not be pleased with the typical "spider web" wiring that is done in many new homes today, so the question becomes what is acceptable to each person. I think using troughs and j-hooks (or cable stackers) not only look better but provide for a better overall result than staples and a lot of holes. I know a lot of people that are fine with "out of sight, out of mind" for stuff like this as long as it meets code. I'm just not "wired" that way.
 
I'm thinking that for the vast majority of projects discussed on this forum, someone will wonder for at least a part of each project "why bother". I know I have done so many times because the project is something that doesn't interest me or the outcome doesn't matter to me, but I know the most likely answer is "because I want to".
 

RAL

Senior Member
If it were me, I would simply mount running boards across the bottom of the joists and staple the cables to them.  It would give an equally organized result, although the cables would be visible rather than hidden in the troughs.  But in a crawl space, I wouldn't care about them being visible.  And I could spend the several thousand bucks saved on something else.
 

wkearney99

Senior Member
I hear you on the OCD-like aspects.  It is tempting to go for "that perfect look".   Have at it, and share the eventual pix.   :D
 

Neurorad

Senior Member
I'm unsure if you should use Romex in a raceway, in a damp location (would that be considered damp?).  Since there is no inspector, do you need to follow NEC guidelines? Is there a nearby AHJ to consult?
 
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