Type NM cable installed on a wall of an unfinished basement or crawl space subject to physical damage must be protected in accordance with Sec. 300.4, or be installed within a raceway with a nonmetallic bushing or adapter at the point where the cable enters the raceway, and the NM cable must be secured within 12 in.

Can nm B cable be exposed?

The National Electrical Code forbids the use of NM cable in situations where it is exposed in a manner where physical damage is possible.

How often should NM cable be secured?





every 4 ½ ft.

NM cable must be supported and secured every 4 ½ ft. and within 12 inches of every outlet box, junction box, cabinet, or fitting. Secure and support. Where nonmetallic cable is installed horizontally through holes or notches in framing members, it is considered supported and not required to be secured.

When can NM cable be exposed?

If the NM cable is installed where it passes through a floor, the cable must be protected for at least 6 inches above the floor by enclosing it in rigid metal conduit, intermediate metal conduit, or one of the other methods previously mentioned.

Do cables need mechanical protection?

There is no need to mechanically protect wires in domestic situations as it would take a deliberate act to damage visible wires.

How do you protect exposed nm wire?





Nonmetallic-sheathed cable must be protected from physical damage by rigid metal conduit (RMC), intermediate metal conduit (IMC), Schedule 80 PVC conduit, Type RTRC-XW conduit, electrical metallic tubing (EMT), guard strips, or other means approved by the authority having jurisdiction (AHJ) [334.15(B)].

Is Romex allowed to be exposed?

Romex is a brand name of non-metal sheathing wire. To give you an overview of what the National Electrical Code (NEC) regulations state, Romex wire shouldn’t be left exposed anywhere in the house, be it the basement, attic, or the home itself.

Does Romex need to be stapled?

Quote from the video:
Quote from Youtube video: It actually says under securing and supporting non-metallic sheath cable shall be supported and secured by staples cable ties listed and identified for securement.

Can Romex be exposed in garage?

As electrical wirings are found everywhere homeowners often wonder – can Romex be exposed in the garage? The short answer to the question is – no, you should never expose your Romex wiring in your garage. You should always cover Romex wiring on your property.

How far apart does Romex need to be secured?



Article 336-18 stated that cable must be secured in place at intervals not exceeding 4.5 feet (1.37 m) and within 12 inches (305 mm) from every cabinet, box, or fitting.

Do cables need to be protected in walls?

If the wall is made from metal then it will need RCD protection, or. The cable should be armoured with an earthed armour or metal sheath, or. The cable should be in metal trunking or conduit which is earthed or, It should have protection from at least 3mm steel.

What is classed as mechanical protection for cables?

Mechanical protection is protection against mechanical damage such as being knocked or bashed.

Should cables be protected in walls?



All electrical cables should be set into the walls at a minimum depth of 50mm if they are not mechanically protected. If it isn’t possible to chase the walls to that depth then the cables should be set deep enough so that metal capping can cover them and allow for plaster to cover that.

Do cables have to be capped?

So if cables are on a block wall that is to be plastered or rendered, you should protect it from damage by a plasters trowel for example. So you fitted capping.



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Is it OK to plaster over cables?

No problem plastering straight over cables but if you think you might ever want to pull them out put some plastic capping over them first.

How do you protect electrical wires in the wall?



Quote from the video:
Quote from Youtube video: And you hammer it down so that it's pretty much flush with the wood. Now. When you are screwing drywall into place or if you are putting any screws into the wood.

Is Romex wiring safe?

Romex wire is one of the better and safer alternatives for the following reasons: Presence of a ground wire. Sheathing is flame-resistant and heat resistant, able to withstand a temperature of 90 degrees Fahrenheit. Longer-lasting due to copper metal composition.

What is an NM cable?

Type NM stands for nonmetallic sheathed. The cable consists of a factory assembly of two or more insulated conductors within an overall nonmetallic jacket. Additionally, there is an equipment-grounding conductor that is bare or has green insulation.

How many nm cables are in a bored hole?

The Answer. According to the National Electrical Code, you can have 4 12/2 nonmetallic sheathed cables through a single bored hole that is fire- or draft-stopped using thermal insulation, caulk, or sealing foam, or where proper spacing is not maintained for more that 24 in.

How often does Romex need to be supported?



General Cable Support



Runs of NM cable must be supported at least every 54 inches. 1 They also must be secured within 12 inches of an electrical box that includes a cable clamp or within eight inches of a box or enclosure without a cable clamp.

Can you staple two Romex wires together?

When stacking multiple Romex wires under one staple, the general rule of thumb is to always wire just one wire per stable, and if you really must, staple no more than two wires side by side. In the field, anything more than two wires at a time is known as a stack.