NMB in floor joist cavity

Status
Not open for further replies.
G

GCelectric

New member
My question is: Is NMB cable allowed to remain in a floor joist section that did not have air return panning for forced air furnace before the new furnace was installed ? Has anyone been required to relocate these cables before or is it allowed because of any grandfathered clause?
 
Welcome to the forum.:)

In my opinion you would not be able to "grandfather" this type of installation. If you are changing the use of the floor joist cavity to become a cold air return then I would say that the NM cable running parallel with the cavity would be a violation and would have to be moved.

JMHO,

Chris
 
raider1 said:
Welcome to the forum.:)

In my opinion you would not be able to "grandfather" this type of installation. If you are changing the use of the floor joist cavity to become a cold air return then I would say that the NM cable running parallel with the cavity would be a violation and would have to be moved.

JMHO,

Chris
Click to expand...

However, if you traverse the return it is legal-- go figure...
 
Dennis Alwon said:
However, if you traverse the return it is legal-- go figure...
Click to expand...

I think the exception to 300.22(C) is a concession due to the fact that logistically it would be tough to wire a home with a basement and not run NM cable perpendicular through a cold air return built using a panned off floor joist space. That just my thoughts.:)

Chris
 
raider1 said:
I think the exception to 300.22(C) is a concession due to the fact that logistically it would be tough to wire a home with a basement and not run NM cable perpendicular through a cold air return built using a panned off floor joist space. That just my thoughts.:)

Chris
Click to expand...


Guess you haven't wired too many homes with LVL's everywhere... ;) :grin:
 
iwire said:
Neither have I, how does that change things? :-?
Click to expand...


Agreed, you are permitted to drill an LVL according to the manufactures installation instructions so I don't see how this is any different than usign nominal lumber or I joists.

Chris
 
stickboy1375 said:
Guess you haven't wired too many homes with LVL's everywhere... ;) :grin:
Click to expand...

I just did a house with no less then 30 LVL's--- I avoid drilling them but I will if I have to. I also drill them over a wall if possible but generally there is no problem with a 3/4" hole.
 
iwire said:
Neither have I, how does that change things? :-?
Click to expand...


You can only drill where the manufacture lets you... and only so many holes, but its up to the manufacture, It can be a real PITA to run all your feeders in a basement with LVL's installed everywhere.
 
Last edited:
Dennis Alwon said:
I just did a house with no less then 30 LVL's--- I avoid drilling them but I will if I have to. I also drill them over a wall if possible but generally there is no problem with a 3/4" hole.
Click to expand...


Dennis, i've seen inspectors fail houses because of alarm guys drilling 3/8 holes in them, not something to mess around with....
 
stickboy1375 said:
Dennis, i've seen inspectors fail houses because of alarm guys drilling 3/8 holes in them, not something to mess around with....
Click to expand...

That may be but I called the manufacturer and they told me that a 3/4" hole would not be a problem if you drilled it in the middle of the width--- anywhere along the length. Go figure.
 
Dennis Alwon said:
That may be but I called the manufacturer and they told me that a 3/4" hole would not be a problem if you drilled it in the middle of the width--- anywhere along the length. Go figure.
Click to expand...

It can be a real pain always calling manufactures on what you can and cant do...
 
around here i never had a problem drilling an LVL. usually i go in the middle but if i cant i cut the strapping below it and throw a nail plate over once i run the cables. just drill in the middle of the joists or lvl's and you wont have a problem
 
electricalperson said:
around here i never had a problem drilling an LVL. usually i go in the middle but if i cant i cut the strapping below it and throw a nail plate over once i run the cables. just drill in the middle of the joists or lvl's and you wont have a problem
Click to expand...

If you dont follow the directions you could have a problem... They are engineered... You cant just modify them... they have strict restrictions on hole locations.
 
Status
Not open for further replies.
Top