Cutting a groove in the BOTTOM of a stud for wiring
A while back I was looking online at some articles on “new construction” techniques and ran across an idea for cutting a groove or “v” shaped notch in the bottom of studs before they are assembled in the wall to provide a path for wires. The idea being a whole row of studs can be cut with a saw more quickly than drilled and batt insulation can be installed with out compressing or slitting to go around the wires.
I mentioned this to the building inspector and tried to find out if this was acceptable. He said he couldn’t speak for the electrical inspector as to whether or not it was acceptable. I was just asking from a framing stand point. I really don’t think he understood. I mentioned several other things, like two corner studs with drywall clips and he said it didn’t meet code. These guys here (NM, small county) don’t want to change their way of thinking or learn antything. He just said we could fix any problems after they inspected. Who wants to FIX problems! I want things designed and built correctly!
The only reference I could find when I went looking again is this: https://www.finehomebuilding.com/how-to/tips/energy-saving-sole-plates.aspx?nterms=61672,65824 (from 1982!) It talks about cutting a groove in the sole plate, which I don’t think is a good idea, because you are removing more total material, and I think it would weaken the sole, but I can find no references to grooves or notches in the BOTTOM of a stud. I would think the same rules for 40% for a hole or even 25% for a notch in IRC 602 would apply. At 25% in a 2×4 would allow a 7/8ths notch, which should be enough for at least two 12-2 or 12-3 wires.
Anyone have any comments or references why it would or wouldn’t be in code compliance from both construction and electric code stand points?
Thanx
Replies
A grove in the sole plate won't compromise a thing. Most of the loading on the sole plate is compression, so lateral forces are at a minimum.
Now ask me, as an electrician, if I want to crawl around on my knees pulling wire in your groove or notched studs.
OK, I'll do it, but you are going to pay extra for my sore knees and back. Your call. Who gets paid more, the electrician or the insulator?
A decent electrician and a helper can rough in a 2000 sf house in a day to day and a half, using the standard drill and pull method. Put them on thier knees crawling around and my guess would be over two days,
If you are worried about slitting fiber glass insulation to fit around wires, just use dense pack cellulose or spray foam. Better choices to start with and air sealing to boot.
or use a dual wall and have absolutely nothing in the way of the current or any future wires.
yeah, but......... all of the options y'all mentioned would be considerably more expensive than an extra day of an electrician's time.
In addition to what Dave said, remember that standard practice is to position electrical wires 1.25" into the wall, so drywall fasteners won't reach them. That's a pretty deep dado to cut in the studs. I'd much sooner bore holes up higher.
Hole boring goes pretty quick, especially with a "wood butcher" bit (spade bit) and a stout right angle drill.
I'd also be worried about the trim carpenters installing the baseboard. They can shoot long trim nails at times.
No on the notch
I think. IRC 2006 sez R602.3.4 Bottom (sole) plate. Studs shall have full bearing on a 2x bottom plate.
However, 2 stud corner with DW clips is addressed on page 129. Lower right pic note says "Note: a third stud shall be permitted to be omitted if clips or other approved backing device is used."
Scraps of sheathing work for me, don't need no stinking cleeps.
Where you at here in NM, the Land of Enlightenment?
In a state where half the building stock is tornado modified trailers it's surprising they even have a building code.
Joe H
In a state where half the building stock is tornado modified trailers it's surprising they even have a building code
Roar!
I did my first house that way ... cutting a notch in the center of the 2x6 studs. Personally, I don't think there is a big advantage in doing it. My last house I made a plywood jig so all my wiring holes were e.g. exactly 12" up. Cutting batts to length is a piece of cake to fit around the wire. Yeah, an extra cut, but no big deal. You can quickly cut a couple dozen lengths for the bottom and then do the top lengths.
As for the 2 stud corners ... Your BO is washed up! I used the drywall clips and 2 stud corners in 1980 on a house ... it was inspected and approved. Personally, I don't care for them, but it is a designed method. I'd rather nail scrap plywood to the back side of the stud (great use for scrap plywood) or use a 3 stud corner w/ the 3rd stud turned 90 to give you the support lip ... although that is a waste of a stud for little benefit. The 2 stud corner meets code everywhere I've been. The 3rd stud isn't even structural. You're right ... he doesn't want to change an old mindset.