NMB (romex) under a house

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JDB3

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San Antonio, Texas
A 1950's ranch house built on pier & beams. Currently has 7 single pole breakers in the inside panel. Looking to upgrade the whole works.
What is your opinion & code on installing romex under the house (stapling it to the floor joists to keep it off the ground. Attic would not work in a "bunch" of areas due to the slope of the roof.
Thanks in advance! ;)
 
Is the underside of the house enclosed or open so as to meet the definition of "damp location" ? If "damp[" you could not install NM.
NM or UF would need to be installed thru bores holes or have running board protection,
 
If this is a crawl space NM is perfect.


334.15 Exposed Work.
In exposed work, except as provided in 300.11(A), cable shall be installed as specified in 334.15(A) through (C).
(A) To Follow Surface. Cable shall closely follow the surface of the building finish or of running boards.
(B) Protection from Physical Damage. Cable shall be protected from physical damage where necessary by rigid metal conduit, intermediate metal conduit, electrical metallic tubing, Schedule 80 PVC conduit, or other approved means. Where passing through a floor, the cable shall be enclosed in rigid metal conduit, intermediate metal conduit, electrical metallic tubing, Schedule 80 PVC conduit, or other approved means extending at least 150 mm (6 in.) above the floor.
Type NMC cable installed in shallow chases or grooves in masonry, concrete, or adobe, shall be protected in accordance with the requirements in 300.4(F) and covered with plaster, adobe, or similar finish.
(C) In Unfinished Basements and Crawl Spaces. Where cable is run at angles with joists in unfinished basements and crawl spaces, it shall be permissible to secure cables not smaller than two 6 AWG or three 8 AWG conductors directly to the lower edges of the joists. Smaller cables shall be run either through bored holes in joists or on running boards. NM cable installed on the wall of an unfinished basement shall be permitted to be installed in a listed conduit or tubing or shall be protected in accordance with 300.4. Conduit or tubing shall be provided with a suitable insulating bushing or adapter at the point the cable enters the raceway. The NM cable sheath shall extend through the conduit or tubing and into the outlet or device box not less than 6 mm (? in.). The cable shall be secured within 300 mm (12 in.) of the point where the cable enters the conduit or tubing. Metal conduit, tubing, and metal outlet boxes shall be connected to an equipment grounding conductor.
 
The underside of the house is enclosed, with a tight fit to get under it. I was told that once you got under it, you had enough room to move around.
 
JDB3 said:
The underside of the house is enclosed, with a tight fit to get under it. I was told that once you got under it, you had enough room to move around.
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Then NM is fine. Install per Post #3
 
Hv&Lv said:
If this is a crawl space NM is perfect.


334.15 Exposed Work.
In exposed work, except as provided in 300.11(A), cable shall be installed as specified in 334.15(A) through (C).
(A) To Follow Surface. Cable shall closely follow the surface of the building finish or of running boards.
(B) Protection from Physical Damage. Cable shall be protected from physical damage where necessary by rigid metal conduit, intermediate metal conduit, electrical metallic tubing, Schedule 80 PVC conduit, or other approved means. Where passing through a floor, the cable shall be enclosed in rigid metal conduit, intermediate metal conduit, electrical metallic tubing, Schedule 80 PVC conduit, or other approved means extending at least 150 mm (6 in.) above the floor.
Type NMC cable installed in shallow chases or grooves in masonry, concrete, or adobe, shall be protected in accordance with the requirements in 300.4(F) and covered with plaster, adobe, or similar finish.
(C) In Unfinished Basements and Crawl Spaces. Where cable is run at angles with joists in unfinished basements and crawl spaces, it shall be permissible to secure cables not smaller than two 6 AWG or three 8 AWG conductors directly to the lower edges of the joists. Smaller cables shall be run either through bored holes in joists or on running boards. NM cable installed on the wall of an unfinished basement shall be permitted to be installed in a listed conduit or tubing or shall be protected in accordance with 300.4. Conduit or tubing shall be provided with a suitable insulating bushing or adapter at the point the cable enters the raceway. The NM cable sheath shall extend through the conduit or tubing and into the outlet or device box not less than 6 mm (? in.). The cable shall be secured within 300 mm (12 in.) of the point where the cable enters the conduit or tubing. Metal conduit, tubing, and metal outlet boxes shall be connected to an equipment grounding conductor.
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Off the original topic so forgive me. If I'm wiring a two-story home and I protect all NM-B cables that pass through floors with metal conduit in accordance with (B) above, do these pieces of metal conduit need to connected to an EGC as stated in (C) or is that just limited to unfinished basements and crawl spaces. The reason I'm asking is because looking at Art. 250.4 (A) (3) it implies that it does. If so, I'm just wondering why it was included in (C) and left out of (B).
 
Rick 0920 said:
Off the original topic so forgive me. If I'm wiring a two-story home and I protect all NM-B cables that pass through floors with metal conduit in accordance with (B) above, do these pieces of metal conduit need to connected to an EGC as stated in (C) or is that just limited to unfinished basements and crawl spaces. The reason I'm asking is because looking at Art. 250.4 (A) (3) it implies that it does. If so, I'm just wondering why it was included in (C) and left out of (B).
Click to expand...
Unless the wiring is exposed in this two story home 334.15 doesn’t apply.
 
No worries with NM, the mice love that stuff. Lol.
 
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