Types of Residential Conduits:
Ways of Routing Electricity throughout the Home Depend on Application and Building Code
© 2008 by Kelly Smith all rights reserved; content may not be copied, rewritten, or republished without authors written permission
Residential electrical conduits may be Romex, rigid metal conduit, armored cable conduit, or PVC
conduit. Local building codes will spell out requirements during a remodel project or new construction.
The electrical current that supplies power the home enters at one location. Its then distributed
through the residence from the fuse box, circuit breaker box, or electric service panel. The gauge
of the wire bundle and the conduit which contains it is spelled out by your local electrical building code.
An option is to go above and beyond mandated requirements, which you will appreciate further down the road.
Before beginning a wiring project, its important to
understand home wiring
Nonmetallic Cable (NM cable or Romex)
Nonmetallic Cable (NM cable or Romex)The most common wiring cable youre likely to encounter.
This is specified for almost all applications, is easy to work with, and is very affordable. Upgrades
from Romex are widely used in commercial work, on exterior lighting and buried: armored cable, metal
conduit, as well as PVC conduit (great for landscape lighting).
Using Armored Cable Conduit
Always check your local electrical building codes and pull the required permits; some municipalities
now require using armored cable conduit rather than Romex, although its more common in commercial
construction. Its a good upgrade; the price isnt much more, and its much safer than Romex.
Armored cable is really just coiled metal sheathing with the wire bundle inside. Its almost
as flexible as Romex, however it protects against nail punctures when hanging drywall, hammering in
nails to hang pictures, and other mishaps.
To work with and cut armored cable, bend it smartly until its coils begin to separate. Then, carefully
twist the coils apart until enough wire is exposed. Use straight-cut aviation snips or side-cutters to
cut away any excess cable.
Using Metal Conduit for Residential Wiring
Usually commercial construction comes to mind when thinking rigid metal conduit. But as a matter of
fact, its a good choice for residential wiring in areas such as attics, garages, basements, as
well as crawlspaces.
Mice are fond of chomping on electrical wires in these spaces. Rigid metal conduit will
bring this destructive behavior to a quick end.
Working with rigid metal conduit is a bit different. Youll need a commercial conduit bender,
offset fittings, conduit couplings, and elbows.
Its also different from armored cable in that metal conduit doesnt come from the manufacturer
with the wire bundle factory installed. The wires are pulled through the metal conduit manually after
the conduit is installed.
For very long runs, or where there are many sharp turns between point A and point B, wire-pulling
is made easier using a wire-pulling lubricant made for this purpose.
When a very flexible connection off a box is required, Greenfield is used. (Its like
armored conduit except without the wire bundle.)
PVC Conduit for Residential Wiring Applications
PVC conduit is just the ticket for home exterior applications. Its very versatile considering the
broad range of connections available. Assembling a PVC circuit is similar to a plumbing project. The
difference is that the goal is to keep the water out, rather than in!
So hows it assembled? PVC conduit is rough-cut using your hack saw. Then the conduit lengths and
fittings are connected using PVC primer and glue to achieve a waterproof conduit.
Which applications favor PVC use? Two places leap to mind: outdoor lighting and buried underground.
The benefits gained in either area are first waterproofing, and secondly having confidence in a
Residential Conduit Conclusion
In conclusion, the methods of channeling electrical transmission in the residence is dependent on
several factors: local building codes, the environment, economy, and of course, safety.
If youre not comfortable doing the work. find a licensed electrician in your area, check out
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