Running NMB under floor along a joist in old construction
#1
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How do you run NMB under floor along a joist in old construction?
#4
The cable must be fastened to the joist (or pass through a small hole in the joist) at intervals not exceeding 4-1/2 feetl and again within 12 inches of an outlet box or or panel box etc. it enters without a box clamp. However if it is necessary to rip open floor or ceiling or enlarge a fishing hole for the sole purpose of stapling the cable (or for drilling a passage hole in the joist not absolutely needed for the cable to get from point A to point B), then that staple/hole may be omitted/skipped/neglected.
Last edited by AllanJ; 09-21-16 at 06:45 PM.
#7
Cables fished through finished spaces only need to be stapled where it is accessible. Otherwise you can use a fish tape or rods to get the cable through the closed bays with only limited disruption of the wall/ceiling finish material.
Note that because this is living space above a garage you are working with a rated fire wall, so make sure you're cognizant of that per your building code.
Note that because this is living space above a garage you are working with a rated fire wall, so make sure you're cognizant of that per your building code.
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Yeah its a bonus room, and builder only put one outlet....
Under the floor there are many nails and screws from the plywood underlayment and wood flooring.
Am I allowed to use, and leave in, a piece of UNSECURED conduit to protect the wire when fishing?
Under the floor there are many nails and screws from the plywood underlayment and wood flooring.
Am I allowed to use, and leave in, a piece of UNSECURED conduit to protect the wire when fishing?
#9
If the nails are in the floor of the attic and you are fishing cables they will lay on the ceiling of the garage and the nails above are not an issue. How did you plan to get a conduit into a finished ceiling?
#10
I do not believe the code allows fished conduits; it only specifically mentions cables. An unsecured conduit could be more harmful to the wiring as the edges or fitting could abrade the insulation.
#11
What exactly are you trying do,do you have access to this,if joists are exposed you would staple the cables horizontally along them,or run a board perpendicular with them and staple the cable yo it.
How about some pics so we can see your situation.
How about some pics so we can see your situation.