What is the best strategy to accomidate electrical wire runs in new construction when the attic will largely be finished. If the wires are run as is typical, over the rafters, the flooring install will be an issue. I assume drilling rafters is a code no no. I have not spec’d in engineered trusses in the attic floor (allowing ample space for runs) but I am having it engineered for load. Any thoughts on an electrician friendly / owner economical solution? Thanks in advance.
Lastly, I hear wire is going absolutley crazy in price. Should I purchase now for 4Q06 Construction?
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Well, they are floor joists, even in the attic ;-)
And you can drill them for wires just like any other floor joist...same rules....
A classic "assuming" incident...ya know!!!!
What calender year is 4Q06.......Hee Hee
4th quarter 2006. 4Q06.
So I can drill. That is good news. Wire has always gone through engineered web and over attic floor joists. Was not sure and wanted to verify before encountering a code issue. Thanks for the input.
Chances are you're going to have knee walls in attic?
Why not route the wires behind where the knee walls will be placed?
"I have not spec'd in engineered trusses in the attic floor (allowing ample space for runs) but I am having it engineered for load."
So what ARE you using? 2X lumber? I-joists?
I-joists have specific instructions for where you can and can't drill holes. The manufacturer's literature will have info on that.
If you do end up using attic trusses, you can't just drill holes in them like you can with typical 2X floor joists. Contact the manufacturer for info on your specific situation.
Most attics that I've been in have an unused space outside the kneewalls. You can get a heck of a lot of wiring out there running perpendicular to the floor system and not have to drill anything.
Still waiting to get the engineering plans back but last time he spec'd in mostly 2x6 lumber. I am sure any penetrations in the engineering spec would need his signoff. I am just wondering if it would not be better to have web-trusses instead of the engineers 2x spec'd.
I should have knee walls on one side. The back side will have an attic dormer with a deck. Thus the finished attic part. Behind the knee walls and along the joist runs should be the answer. Just have to buy more wire I suppose.
I'm a little confused, are you saying you are going to be running 2x6's as floor joists for a finished attic....or the bottom cord of the truss's are 2x6's?
I don't know about trusses, though a 2x6 for a floor joist seems way to small
What CAGIV says -- unless there's a very steep roof you're apt to have a knee wall with unfinished area behind. Running wires pushed back into the rafter/joist corner is actually preferred, since they're less likely to be stepped on or otherwise damaged vs running in a more central location.
Copper prices seem to be past the panic peak, and as construction slows down in the winter, may ease off even more. So, I'd hold off until you need the wire. If you can find old stock that hasn't been marked up, though, grab it.
-- J.S.
If the wires are run as is typical, over the rafters, the flooring install will be an issue
That will depend on how much of the attic, how it is floored. If you are only flooring where there's living space, and maybe some adjacent storage decking, using all diagonal sip flooring for the sub floor gets you some "relief space" for wires "over" joists.
I'd make sure to have a major sit down not just with the electrical sub, but the electrical leadman with the plans, and point out where you're putting in finished space. Far cheaper to run "around" now, than take a stray nail into a wire. Better for the electrical guys too, if they get a call back for some mystery circuit problem later, too (no havign to remember "Did we run under, or around?"
Lastly, I hear wire is going absolutley crazy in price. Should I purchase now for 4Q06 Construction?
The oil used to make the plastic insulation seems to be the most recent spike in price, with copper mostly settled back down. If you're buying to have some, I'd watch prices for late August, and see if oil costs stay half reasonable. If you're buying to not have to pay a materials markup to the elec sub--well, that can be some tough sledding. The price the electrician starts from is his averaged price buying thousands of feet of cable in all of his used sizes. His pricing for 310' of 14/2 will be different than yours (you'd need to buy two boxes of 250', and you have 200' of "leftovers"). You'd need the complete cable take off, too, to get the right quantity of wire to have on hand (won't help anybody if you're off by 10-15% for quantity).
But, that's just my 2¢.
You're not in Madisonville, are you?