Electric wire stapled to joists vs hole
We passed electric rough-in today, but the inspector took issue with the homeruns in my basement.
Since I am not finishing the area, and I didn’t want to drill the I joists, I stapled the romex (every 4′) to the bottom of the joists. It is secure and neat. His comment was he may ask me to drill the joists and repull the wires at final unless I can show him documentation that the I joists cannot be drilled (the truth is I’m not sure of the I joist drilling rules, so I avoided it entirely) He didn’t seem too confident on what the rules were, so this may be a “preference” issue for him. His final comment “I could be a harda$$, but I’ll go ahead and pass you, so you can start drywall)
What is the code issue here – I stapled my last house (crawl space) and I’d like to leave things the same – is there a website where I could grab the code on this?
Replies
Check the NEC. Romex cables under #8 around here need a backing strip when running joist to joist without boring.
Do you ever have plans of finishing your basement? That's maybe his issue.
Sorry, Just read your post agian. I quess you will not finish your basement
Edited 12/20/2005 9:47 pm ET by VAVince
If he uses a drop ceiling, then it wouldn't matter if he finished it or not. I guess that would depend on the basement's height.
You know if you have done this in a way that you can fir down to provide a mounting surface for sheet rock and supply the "race-way" effect the inspector wants,and this may only take a few hours and not bang up your nice wire insulation from removing and...etc.SCRIBE ONCE CUT ONCE!
I-joists, at least the ones I've used, had 1 1/2" knockouts in the web. You're not allowed to drill, notch or cut the flanges but are good to go drilling small holes in the webs for wire and water supply lines.
Where the drilling issue comes into play is with larger holes, like you'd need for 3 or 4" waste pipe, ducting, etc.
Romex has to be protected, so the inspector might be concerned about the exposure of your runs.
Edited 12/20/2005 9:55 pm by Notchman
an inspected told me, He did not like romex stapled to bottom due to it would be too easy to use as a clothes hanger and that could damage the wire.. 2+3=7
The reason the smaller gauge wires cannot be stapled to the bottom of the joists has nothing to do with "hanging clothes", you could hang clothes on the wires if they are installed thru holes in the joists. The reason is wire breakage due to deflection of the joists, a "running board" is allowed so that the NM cables are supported by a continous surface and the board helps limit deflection of the joists.
Joists deflect just as much if the wires are run through holes. (More, actually.)And the rule only applies to wires "within reach", as I understand it.
If ignorance is bliss why aren't more people
happy?
Yes DanH but the wires are not stapled to the joists when pulled thru the holes, they "float" with no direct connection to the joist, allowing the joist to flex without putting direct strain on the cables.
2002 NEC Art. 334.15 (C) Non-Metallic Cable, Exposed Work, In unfinished basements where the cable is run at right angles with the joists in unfinished basements, it shall be permissible to secure cables not smaller than 2-#6 or 3-#8 conductors directly to the lower edges of the joists. Smaller cables shall be run either thru bored holes in joists or on running boards.
Your my kind of poster - makes a statement backed up up by documentation and totally devoid of opinion and conjecture. Around here, all some guys have in conjecture and their "deductive reasoning"... It gets old.
Thank you Matt, I used to share my 30 years experienced opinion here, but soon found out that a couple of people were sure quick to "correct me" so I now only state the NEC Code or documentable info.
PS, BillH, it has everything to do with deflection of the joists, talk to a structural engineer, or the NFPA or post it on electrical-contractor.net where professional, licensed tradesmen, with years of experience can answer that for you.
Oh and plumbing pipes are not directly connected to the bottom of the joists, they used to use bellhangers or 2-hole strap, which allow some movement, thats why a lot of the plumbers now use J hooks, isolated clamps/plastic straps on TJI's because the pipes either broke the bellhangers with expansion and deflection or they made noise.
Go to any engineered joist manufacturer's website, read the fine print , and they all say that for a "superior floor system, blocking should be installed midspan to prevent deflection" Then go to multiple job sites and see who does this. Almost nobody, I had to coerce my framer and pay him extra to do it. You can jump up and down and the China doesnt rattle in my house.
BTW, Bill, when is the last time you got your hands dirty in the field, or are you just a desk jockey? ;-)
I'm with you on that one Bigman.Autonomy on the board makes many stone throwers. Another reason to fill out that profile!Stu
LOL Stu, I know what you mean, anybody that puts their "opinion" on these posts should at least fill out the profile page, I have also noticed that there are an awful lot of "armchair generals" around here, but after awhile you know who is full of BS and who knows what they are talking about. Happy Holidays to all!!!
I don't buy deflection as reason for not allowing stapling to the bottom of the joist either.Never saw any referene to that in the past.A single 1x2, which is enough for a couple of cables, is not enough to prevent any deflection.Seen too many old house with it cables stapled to the bottom of the joist.Andd what about copper and PVC pipe that is just run across the bottom of the joist.
if its not deflection, then what ?
The Code allows cables to be run at angles with joists, or thru bored holes ...no wording for running with the joist ...on the bottom of it....
perhaps the AHJ is going to want the stuff in pipe then
I think that it was has been posted early, chances of being accidently snaged and also used for hangers.
yet another reason to NOT allow it to be run exposed......there, that oughta start something
Baring any authoritative reference from a "structural engineer, or the NFPA" I tend to agree with your view that deflection doesn't seem to provide much of an answer.Those staples are not welded to the cable, ideally they are just slightly more than touching the cable jacket, and the cable is never pulled very tight. Usually it is just tight enough to keep it from noticeably sagging. Typically I can give the cable a pull and get a significant amount of slack out of a run of any length without damaging the cable. Hard to believe that a joist would deflect more than a couple of inches or that even that much deflection would cause a problem. A 1/360 deflection would be 1" in 30' of span. maybe I'm lacking imagination but even double that, 2" of deflection, I have a hard time imagining that compromising a decently installed cable run. Perhaps I can corner one of the inspectors and see what he, or she, says.
The deflection isn't up and down, its side to side twisting (which is why they recommend mid-span blocking), which causes stress along the wire length. And NM cable is generally stapled way to tight, (haven't you ever traced a short to an indented staple?) that is one of the reasons the insulated SN-40 staple is required by the BI's in our area of CT.
A good tradesmen makes the effort to install the NM cable properly, the problem is there aren't enough guys that pay attention or even care about the quality of the installation.
> The deflection isn't up and down, its side to side twisting (which is why they recommend mid-span blocking), which causes stress along the wire length.
This sideways twisting of the bottom edge of the joist also allows the top of the joist to bend downward. Basically, the bottom of the joist moves out of the position where its resistance to tension is needed. Blocking prevents that, and therefore makes the floor more solid against vertical loads.
That's the main reason for it, and it has the added good effect of eliminating the motion that would otherwise affect the wires.
-- J.S.
BINGO!!! Thank you J.S.
The difference between the basement and the crawlspace is that in spite of your current intentions, the basement, as opposed to a crawlspace, could be finished in the future and those wires would not be in a protected position.
"...I stapled the romex (every 4') to the bottom of the joists."
I doubt that stapling romex every 4' is acceptable.
The comment about using the wires to hang stuff from is the reason romex isn't typically allowed on the bottom of joists.
With respect to building "code" on the I-joists, it is wahtever the manafacturer says it is. As notchman said, all the ones I have used have knock-outs. I'd sure hate to have to have you re-pull all your wires, but it would be a lot easier now...
I don't know what the NEC says about that siuation though.
You know that someone, one day, is gonna want to finish that basement though...
BTW - remember that many states use different building codes and then you got Canada, Europe, etc, etc.
The basic idea is that smaller cables, in areas where folks might be inclined to hang things from them, must be routed through the joists or have a strip under them to prevent someone from hanging a coathanger on them. Crawlspaces aren't a problem, obviously, since few people hang their clothes there.
happy?
Around here, the issue is that the cables have to be "protected" from being hit, or snagged or something like that. In practice, these means they get sheathed in conduit of some type if the are below 8' high and below joists.
So you might also be able to box them in, if they are all pretty much together.
"He didn't seem too confident on what the rules were, so this may be a "preference" issue for him." Wether or not the inspector is well versed in the specifics of the Code (sadly, most are not), it is not a preference, but a violation. One that I fully agree with. Frankly, you are lucky that the inspector passed the rough-in. Had he/she actually been a hardcase, they could have probably sited you for many violations.
The joist can be drilled in the proper locations. This IS readily available on the manufacturers' websites.
The NEC can be purchased from some book stores and from a couple dozen places online. Find out which version applies to your location and to your permit(s). Buy it and get someone that understands it to help you to understand it. It is not the easiest document in the world to read and make sense of, though you should do so.
"It is secure and neat." That may be your opinion of all your hard work, but if you have unprotected NMB cable transversing the bottom side of floor joists, it is certainly not secure. It is also very poor practice. This, my friend, is why so many professionals despise the uninformed HO/DIY.
My paraphrased version of the applicable Code language is: Anywhere that NMB (aka Romex) "is subject to possible physical damage" , it is not allowed per the NEC (NFPA 70). It has nothing to do with neatness or the inspector being difficult. It is a mistake on your part and it needs to be corrected. The reason that you were allowed to get away with this previously is that a crawl space is, by definition, not an occupied space, where a basement, regardless of the finishes inplace or planned, is an occupied space. In an occupied/occupieable space people move themselves and sometimes heavy damaging objects around and that PVC coated live wire hanging across the bottom of the floor joist is simply a very vulnerable target.
The NEC can be purchased from some book stores and from a couple dozen places online. Find out which version applies to your location and to your permit(s). Buy it and get someone that understands it to help you to understand it.
Great advice. It amazes me how many apparently try to "play the game" without having a copy of the "rule book" in hand. In many cases they've never even laid eyes on a copy.
....." . Find out which version applies to your location and to your permit(s).......". what version ??
> ....... what version ??
NEC gets updated every three years. Some local building departments adopt the new ones quickly. Others may lag a version or two behind, or spend some time re-writing their own exceptions.
-- J.S.
I thought the "version " he was referring to meant ...regional or some weird thing like ...High Desert Edition, or ..Great Lakes NEC.......LOL
I am no electrician, but I know this code, to some extent, because I have a copy (1996) and I read it and I got help from electrical installers and designers to interpret the applicable portions that weren't clear. I did this so that when I wired my home it would be done right and that it would be done safely. There is no excuse for anyone doing any electrical work, professional or amatuer, not to do the same. If you DIY poorly on many facets of the home, the only real consequence that it may look crappy, perform poorly, or devalue the property. Some plumbing and HVAC mistakes can kill as well, especially those that involve combustible or deadly gases, can cause great harm as well. Electrical work done poorly will very likely eventually kill someone. The best case scenario is that no one is harmed in the process.
> Some plumbing and HVAC mistakes can kill as well, ....
Plus structural mistakes, too.
-- J.S.
Plus structural mistakes, too.
True: http://www.answers.com/topic/hyatt-regency-walkway-collapse
True, but fortunately, most significant structural projects are beyond what an unskilled individual will attempt. You can walk into Home Depot or Menard's or Lowe's, et al, and purchase all the material/components that you need to wire a house, with the possible exception of a meter head. Not too many box stores selling LVLs or truss joists, though dimensional lumber is readily available. You can buy a water heater, all sorts of gas piping materials, those little diverter thingy's that dump dryer exhaust into the living space, all sorts of items that can easily be missapplied or improperly installed.
Personally, and I'm sure the original poster will disagree, I believe the inspector did him and his community a disservice by allowing him to continue.
Actually, you don't need to buy LVL's and such to get into big structural trouble. All those places will sell you a sawzall, which is all you really need to bring the whole house down on your head. I've seen DIY shows on TV where they tore out a wall without any thought as to whether it might be bearing.
-- J.S.
"Personally, and I'm sure the original poster will disagree, I believe the inspector did him and his community a disservice by allowing him to continue."
Although this post has taken on a life of its own, as the original poster, I'll reply w/ what happened:
my wife hung a bunch of clothes on the wires, and the house burned down :-)
actually...
I am drilling the I joists before final inspection. To a 2nd generation builder who has been building off and on since 1988, all the DIY comments seem a little silly.
Thanks for the info everyone...
Treat every person you meet like you will know them the rest of your life - you just might!
Brian, good luck with your project. Hope all works out for you and your family.
"To a 2nd generation builder who has been building off and on since 1988, all the DIY comments seem a little silly."
Frankly, based on the methods you described and lack of code knowledge, everyone assumed that you are a non-professional. As a "2nd generation builder", you should be ashamed. Given the fact that you have already experienced first hand exactly why the NEC dissallows such poor practice, and yet you chose to repeat the same installation, further underscores that assumption. What is "silly" is that you don't know better, having been somewhat involved in the building trade for almost 20 years.
Thanks Tim
You'd really have to see the particulars of the installation before assuming it is poor practice - in this case drilling the joists is functionally identical to the staples but its the one size fits all NEC solution, so I'll go with it even if the difference is negligible.
As for my building experience, its just that - very little electrical - I'm just wiring 1 (my) house to save $, and the electrical inspector (another county) that checked my work could quote chapter and verse of the code from memory but he didn't think drilling was warranted. So not ashamed of any "poor practice", nor feeling any need to read electrical code books - I have electricians for that.
The house burning down part was a joke.
Treat every person you meet like you will know them the rest of your life - you just might!
Alright, you got me on the joke. :)
As far as acceptable or not, take a pic and show us what you did. Based on the verbal description, it "sounds" bad to me.
As far as having "electricians for that", did they or you install the wiring as previously described? If they did (and did it wrong) then they too need to get/read/understand a copy of the current NEC.
You seem to disagree that exposed NMB wiring needs to be protected from physical damage, and therefore don't understand why through the joists is not the same as along the bottom of the joists, regardless of how "secure" it appears.
As far as the inspector that "could quote chapter and verse of the code from memory but he didn't think drilling was warranted". I'm skeptical. IF he could "quote chapter and verse", then he would KNOW, not think, whether the installation meets code or does not. This is black or white. If the inspector knows the code (which is doubtful) then a "yes" or "no" is the answer. "I think" is the realm of incompetents and bullshooters. He is one or the other.
On TOH today (show 2513) they showed where they where blowing foam insulation.This was the underneath of a flat roof. The structure was i-joist with strapping for the later ceiling install.You could clearly see cables run down the side of the i-joist and also across the bottom parallel and about 2" away from the strapping.
in 2005 NEC, Unfinished basements:
cables smaller than (2) #6 or (3) #8 SHALL be run through bored holes in joists or running boards..... ,
sounds like you might lose this one......
the larger cables may be run at angles to the joist
Thanks all - its only 12 or so wires, so no big deal - just a few hours and some sawdust. I'll be sure to hang the wires high so no one is tempted to hang laundry...
Treat every person you meet like you will know them the rest of your life - you just might!
Make sure the hole is in the center third of the joist or you will start another code discussion!
This is a question I was wondering about. I plan to propose it to my electrical inspector, but I try to screen my questions before I go to the inspectors (I'd rather look like an idiot to you guys).
I'm planning to strap my ceiling & floor joists with 2x3's or2x4's. Partly for added stability, partly to help reduce sound transmission. Plus my wall height is currently 97 1/2" & I'd like to do away with a 1" strip at the bottom.
Anyway, if I do this, would I be able to run the wires along the strapping as opposed to drilling through the floor joists?
hold on a minute........
......cables smaller than (2) #6 or (3) #8 SHALL be run through bored holes in joists or running boards.....
the word SHALL , indicates that work will meet the requirement only if done exactly as spelled out in the Code ......
on the bottom of strapping...is at least to me .. still on the bottom and exposed.
no harm in asking the inspector, he may suggest placing strapping on either side of the cables....but I ain't never seen anything like that.
I meant along side the strapping not underneath it.
...went back and reread it, ....I would say yes,
What MD posted for UNFINISHED ceilings.
I assume that you are going to put up DW on the stapping. In that case the section that he referenced does not pertain.
I am not familar with strapping ceilings, but read comments from Mike Smith and others where strapping is common that it is common to run rommex directly on the bottom of the joist.
BTW, they use 1 by for straping and if the desire is to reduce noise transmission I think that would be better than 2by.
As I understand it the running boards are only allowed to be used in unfinished basements, where the wiring is exposed, as per the code section I quoted earlier.
If you plan to sheetrock the ceiling over strapping, you must drill the joists in order to maintain the 1-1/4" clearance to protect the concealed wires from a screw or nail, you cannot run it alongside the strapping.
Merry Christmas to all!!!!
Edited 12/24/2005 12:09 pm ET by Bigman
Here in MA, we strap all finished ceilings with 1x3 strapping. In basements (and living spaces for that matter) wiring is just about always run stapled directly to the joists. In fact I haven't seen a drilled joists (for wiring) in 5 or 6 years other than a floor system opened up for remodeling. Another benefit of the strapping is that it further aids in preventing the joists from deflecting by "rolling" and eliminates the need for mid-span blocking.
I'm not saying one is better, or one is right and the other wrong. Just sharing another common way of doing things. I like the strapping because it also eliminates questionable drilling from ill-informed apprentices and a few lazy bosses. Seems that guys who don't live in areas where strapping is common can't get their head around the idea of strapping and it's many benefits.
'Course you rarely see drywall around here either. 99% blueboard and skim coat veneer plaster.
Not necessary better or worse.... just different. I like hearing about different building practices in different parts of the country. I hear about Tim Uhler's shear wall inspections and it makes me grateful we don't have to deal with that stuff. And then I hear about how Joe (Framer) runs his framing sites where they frame the whole house without a lick of sheathing and then have a "sheathing crew" come behind them. That sounds great to me but it's just unheard of around here. I couldn't find a "sheathing crew" to save my life if I needed one.
I like the diversity offered here. I guess you find what you're looking for though.
"As I understand it the running boards are only allowed to be used in unfinished basements, where the wiring is exposed, as per the code section I quoted earlier."
I don't have a code book handy, but I don't think that it reads as to where running boards are ALLOWEd, but rather list one place that they can be used.
"f you plan to sheetrock the ceiling over strapping, you must drill the joists in order to maintain the 1-1/4" clearance to protect the concealed wires from a screw or nail, you cannot run it alongside the strapping."
Again I don't have a code book handy, but I believe that the clearnace is from the edge of a joist or stud to a HOLE for the wire. Don't run it in a hole and that number does not pertain.
Bill, that 1 1/4" distance is from the face of any nailing surface. Even if wire is run parallel to a joist, it must be held that distance from the edge. 1x3 strapping with wire running beside it would not meet that requirement. Move it out 1 1/4" form the strapping and it does.
The purpose of running boards for the wire is so that no ceiling material can be applied directly over the wire, not for wire support. Type NM cable must be supported every 4 1/2 feet maximum, whether it is on a running board or stapled to the side of a joist.
I'll run this by one of the inspectors next month at our Electric Clearing House meeting and continuing education class.
Dave
That make sense, even though you'd be nailing into the strapping, it would be easy to miss & nail into the wire.
As others has said, if you want to be code compliant, you must either drill holes through the joits or use running boards when using #12 NM cable. If you drill holes the NEC says the hole should be at least 1.25 inches from the edge or be protected by a steel plate 1/16th. You can staple along the length of the joists (just remember to keep them at least 1.25" away from edge. The NEC sections are 300.4(A)(1) and 334.15(B)
Bundling cables opens up a derating issue...
" is there a website where I could grab the code on this?"
http://www.nfpa.org/aboutthecodes/AboutTheCodes.asp?DocNum=70&cookie%5Ftest=1
Scroll down to the area: listed in red: Additional Information about this document and click on the link "preview this document" immediately below same. You will gain a read-only access to the 2005 NEC (uncorrected for TIA/Errata since original publication).
http://www.wisdom-soft.com/products/screenhunter_free.htm