Education

1. FLOOR OUTLETS
Floor outlets are electrical outlets that are installed into a floor area rather than into a wall. Often, a
floor outlet will be equipped with a metal plate to protect the outlet and wiring, along with a cover that
prevents dust and other material from collecting in the outlet when the device is not in use. Outlets of
this type are usually found in dens and living rooms of homes, as well as in conference rooms or
other larger gathering areas in offices and public buildings.
As with any type of outlet, the floor outlet is intended to allow easy access to electrical current.
Because the plug can be placed at any point along the floor, it is possible to strategically position
several outlets within a space, creating easy access to electricity even when a power source is
needed somewhere other than along a wall. When not in use, covers snap or slide into place in
order to protect the outlets and also to allow the floor to retain a smooth surface.
Beneath the surface of the floor, the configuration of the floor outlet is similar to that of a
standard wall outlet. The plugs are housed in an outlet box and normally connected to a central
junction box that helps regulate electric power flow. Wiring runs from the outlet box to the central
junction in the same manner that electrical wiring runs through walls to a central power source.
While it is possible to use plastic or porcelain plates with a floor outlet, the general recommendation
is to utilize metal plates. Durable metal is much less likely to be damaged if the outlet is stepped on
when not in use. The metal covers can hold up well to a lot of weight, which will help to keep the
general appearance of the outlet simple and clean. When necessary, the metal plates can be
outfitted with covers that are spring loaded to snap closed when the outlets are not in use.
In terms of function and appearance, a floor outlet can be helpful in many situations. In a conference
room, an outlet in the floor under the conference table makes it much easier to plug in audio visual
equipment without running extension cords to a wall outlet. In the home, the presence of a floor
outlet in the living room aids in arranging the furnishings, since major seating areas do not have to
remain near a wall in order to include the presence of accent lamps in the grouping.
Installing a floor outlet is very similar to the installation of a wall outlet. As with any type of electrical
wiring project, it is recommended that the installation only be conducted by a properly
certified electrician.
Floor Outlet Covers on wiseGEEK:
 Floor outlets are electrical outlets that are installed into a floor area rather than into a wall.
 Typically, a spring-loaded door covers each plug contained on the outlet unit, making it easy to seal
off access to each plug when the outlet is not in use.
Stumped by the Code? Using Floor Receptacles and Wall
Outlet Requirements, Placing Receptacles on Countertops,
and More
Dec 18, 2012

2. by
Mike Holt
NEC Trainer / Consultant,Mike Holt Enterprises
822 Articles
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COMMENTS 1
Your most pressing National Electrical Code (NEC) questions answered
All questions and answers are based on the 2011 NEC.
Q. What are the Code rules for using floor receptacles to meet the receptacle
wall outlet requirements in a dwelling wall space?
A.Floor receptacle outlets are not counted as the required receptacle wall outlet, if they are
located more than
18 in. from the wall [210.52(A)(3)].
Q. What are the NEC rules on placing receptacles for countertops in a dwelling
unit kitchen?
A.A receptacle outlet must be installed for each kitchen and dining area countertop wall
space 1 ft or wider, and receptacles must be placed so that no point along the countertop
wall space is more than 2 ft (measured horizontally) from a receptacle outlet [210.52(C)(1)].
Exception: A receptacle outlet isn’t required on a wall directly behind a range, counter-
mounted cooking unit, or sink, in accordance with Fig. 210.52(C)(1) in the NEC, as shown
in Fig. 1.

3. Fig. 1. Don’t space out when determining the receptacle locations in a kitchen space.
If the countertop space behind a range or sink is larger than the dimensions noted in Figure
210.52(C)(1) of the NEC, then a GFCI-protected receptacle must be installed in that space.
This is because, for all practical purposes, if there is sufficient space for an appliance, then
an appliance will be placed there.
At least one receptacle outlet must be installed at each island countertop space with a long
dimension of 2 ft or more, and a short dimension of 1 ft or more [210.52(C)(2)].
At least one receptacle outlet must be installed at each peninsular countertop with a long
dimension of 2 ft or more, and a short dimension of 1 ft or more, measured from the
connecting edge [210.52(C)(3)].
The Code does not require more than one receptacle outlet in an island or peninsular
countertop space, regardless of the length of the countertop, unless the countertop is
broken, as described in 210.52(C)(4).

4. When breaks occur in countertop spaces for range tops, refrigerators, or sinks, each
countertop space is considered as a separate countertop for determining receptacle
placement [210.52(C)(4)].
If a range, counter-mounted cooking unit, or sink is installed in an island or peninsular
countertop, and the depth of the counter behind the range, counter-mounted cooking unit,
or sink is less than 12 in., the countertop space is considered to be two separate countertop
spaces.
GFCI protection is required for all 15A and 20A, 125V receptacles that supply kitchen
countertop surfaces [210.8(A)(6)].
Receptacle outlets required by 210.52(C)(1) for the countertop space must be located on or
above (but not more than 20 in. above) the countertop surface. Receptacle outlet assemblies
listed for the application can be installed in countertops [210.52(C)(5)].
Note:Receptacles must not be installed in a face-up position in countertops or similar work
surface areas in a dwelling unit [406.5(E)].
Exception: The receptacle outlet for the countertop space can be installed below the
countertop only for construction for the physically impaired or when wall space or a
backsplash is not available, such as in an island or peninsular counter. Under these
conditions, the required receptacle(s) must be located no more than 1 ft below the
countertop surface and no more than 6 in. from the countertop edge, measured horizontally.
Receptacle outlets rendered not readily accessible by appliances fastened in place, located in
an appliance garage, behind sinks, or rangetops [210.52(C)(1) Ex], or supplying appliances
that occupy dedicated space don’t count as the required countertop receptacles.
An “appliance garage” is an enclosed area on the countertop where an appliance can be
stored and hidden from view when not in use. If a receptacle is installed inside an appliance
garage, then it doesn’t count as a required countertop receptacle outlet.
Q. What is the Code rule for mixing conductors of different systems in the same
raceway, cable, or enclosure?

5. A.Power conductors of alternating-current and direct-current systems rated 600V or less
can occupy the same raceway, cable, or enclosure, if all conductors have an insulation
voltage rating not less than the maximum circuit voltage [300.3(C)(1)], as shown in Fig 2.
Fig. 2. Conductors of different systems can occupy the same raceway, cable, or enclosure if the insulation voltage
rating is not less than the maximum circuit voltage.
Control, signal, and communications wiring must be separated from power and lighting
circuits so the higher-voltage conductors don’t accidentally energize the control, signal, or
communications wiring:
• CATV coaxial cable [820.133(A)]
• Class 1 [725.48]
• Class 2 and Class 3 control circuits [725.136(A)]
• Communications circuits [800.133(A)(1)(c)]
• Fire alarm circuits [760.136(A)]

6. • Instrumentation tray cable [727.5]
• Sound circuits [640.9(C)]
Class 1 circuit conductors can be installed with associated power conductors [725.48(B)(1)],
if all conductors have an insulation voltage rating not less than the maximum circuit voltage
[300.3(C)(1)].
A Class 2 circuit that’s been reclassified as a Class 1 circuit [725.130(A) Ex 2] can be installed
with associated power conductors [725.48(B)(1)], if all conductors have an insulation
voltage rating not less than the maximum circuit voltage [300.3(C)(1)].
PV system conductors, both direct current and alternating current, are permitted to be
installed in the same raceways, outlet and junction boxes, or similar fittings with each other,
but they must be kept entirely independent of all other non-PV system wiring [300.3(C)(1)
Note 2 and 690.4(B)].
Q. What are the GFCI protection requirements for a receptacle installed in a
non-dwelling location if it is under a counter with a sink above it?
A.All 15A and 20A, 125V receptacles installed within 6 ft of the outside edge of a sink in non-
dwelling occupancies must be GFCI protected [210.8(B)(5)].
Exception No. 1: In industrial laboratories, receptacles used to supply equipment where
removal of power would introduce a greater hazard aren’t required to be GFCI protected.
Exception No. 2: Receptacles located in patient bed locations of general care or critical care
areas of health care facilities are not required to be GFCI-protected.
Q. How does the Code address the spread of fire or products of combustion in
regard to fire-rated assemblies?
A.Electrical circuits and equipment must be installed in such a way that the spread of fire or
products of combustion won’t be substantially increased. Openings into or through fire-
rated walls, floors, and ceilings for electrical equipment must be fire-stopped using methods

7. approved by the authority having jurisdiction (AHJ) to maintain the fire-resistance rating of
the fire-rated assembly [300.21].
Fire-stopping materials are listed for the specific types of wiring methods and the
construction of the assembly that they penetrate.
Directories of electrical construction materials published by qualified testing laboratories
contain listing and installation restrictions necessary to maintain the fire-resistive rating of
assemblies. Outlet boxes must have a horizontal separation not less than 24 in. when
installed in a fire-rated assembly, unless an outlet box is listed for closer spacing or
protected by fire-resistant “putty pads” in accordance with manufacturers’ instructions.
Boxes installed in fire-resistance-rated assemblies must be listed for the purpose. If steel
boxes are used, then they must be secured to the framing member, so cut-in-type boxes
aren’t permitted (UL White Book,Guide Information for Electrical
Equipment,www.ul.com/regulators/2008_WhiteBook.pdf).
This rule also applies to control, signaling, and communications cables or raceways:
• CATV [820.26]
• Communications [800.26]
• Control and signaling [725.25]
• Fire alarm [760.3(A)]
• Optical fiber [770.26]
• Sound systems [640.3(A)]
How to Install a Floor Outlet
Say goodbye to hazardous extension cords
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8.  Step-by-Step
 Tools & Materials
 Next Project
Sometimes electricity is just not where you needit,especially in big rooms and in olderhouses.A flooroutlet may be the
perfect way to solve the problem.
By the DIY experts of The Family Handyman Magazine
 Step-by-Step
Put an outlet where you need it
Until someone comes up with a better idea, we're stuck with plugging lamps into outlets to get
light. But what if you want a lamp in the middle of the room where there's no outlet? You don't
have to resort to ugly and dangerous extension cords. We'll show you how easy it is to put the
power where you need it by installing a handsome, stampede-proof, moisture-proof outlet in
your floor (assuming your floor's not concrete!).
Cutting in and mounting the steel outlet box is a job anyone with basic carpentry skills can
handle. Connecting the power is a little trickier because it requires you to locate a suitable circuit
and make electrical connections. If you're uncertain how to do it, consult a basic house wiring
book or a local electrician for help.
Before starting any electrical work, contact your electrical inspections department for a permit. A
permit fee is a small price to pay for the assurance that the wiring is safe, and you might even get
some free advice from the inspector. (See Top 10 Electrical Mistakes to see some common
mistakes to avoid.)
Besides basic tools like a hammer, tape measure and screwdrivers, you'll need a drill and a 3/32-
in. bit, 3/8-in. and 5/8-in. spade bits and a jigsaw. You'll also need a needle-nose pliers, a
pocketknife or utility knife, a wire stripper and a voltage tester.
CAUTION!

9. If you're pulling power from an existing junction box or receptacle, check the color of the bare
wire ends. If they're gray rather than dull brown, they're made of aluminum rather than copper.
Call in a licensed electrician to connect the old aluminum wires to the new copper wires.
Back to Top
Buy a special floor assembly – a regular wall outlet won't do
Photo 1: Find a location
Measure from a reference point, such as the radiator heating pipes shown, to locate the floor
outlet so it falls between the 2x10 floor joists. Then use an 8-in. straight length of clothes hanger,
snipped off at an angle to form a point, as a locator bit. Start the drill slowly while holding the
hanger to keep it from whipping around as you drill through the flooring.
The National Electrical Code requires floor outlets to be a part of an approved assembly
consisting of a metal box, gasket seal, special receptacle and strong cover plate with a moisture-
proof cover. You can't just mount a regular wall outlet in the floor. The first time someone
stepped on it, it would break. Besides, mopping a floor around an outlet that doesn't have a
moisture-proof cover could cause corroded connections, or worse, give you a lethal shock.
The residential floor box assembly we're using may be available at home centers, but if you can't
find one there, you'll find a selection at a local electrical supply store that caters to professionals.
You can find aTamper Resistant Receptacle Floor Box Kit online, available through our
affiliation with Amazon.com.
In addition to the floor box assembly, buy enough cable to connect the outlet to the power
source. With a few local exceptions, you can use plastic-sheathed cable (technically called Type
NM-B). Use 14-gauge wire if the circuit you're connecting to is protected with a 15-amp fuse or
circuit breaker (12-gauge wire for 20-amp circuits).

10. You'll also need at least one plastic cable clamp (Photo 6), wire connectors (Photo 10), 1/2-in.
plastic staples (Photo 10) and 1/2-in. x No. 4 flathead screws.
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Pick a location you can reach with the power cable
Photo 3: Cut a hole for the box
Outline the outlet box on the floor. Drill two 3/8-in. holes at the corners where the screws
protrude from the sides of the metal box and two more where the outlet mounting screws go.
Now use a jigsaw with a wood-cutting blade to complete the box cutout. Apply masking tape to
protect the floor finish.
You can put a floor outlet anywhere, but getting the cable there can be tough. So keep routing
problems in mind when you choose a location. Floors over unfinished basements or crawlspaces
are easy to reach from below. Concrete floors are tougher because you have to cut a trench to the
nearest power source. Floors with a finished ceiling below present a challenge that can usually be
overcome with some ingenuity. SeeFishing Electrical Wire for details on how to pull cable
through finished walls and ceilings.
Locate the floor joists before you cut the outlet hole. Use heat vents, cable or plumbing pipes that
penetrate the floor and are visible from below as reference points. Drill a small hole through the
floor (Photo 1) where you intend to place the outlet and locate the bit from the open ceiling
below. If you drilled directly over a joist, you won't be able to see the bit. Move over a few
inches and try again. Patch the misplaced hole in the floor with matching wood putty. We used a
cut-off clothes hanger as a drill bit because it's cheap, handy and easy to spot from below. This
homemade clothes hanger bit is a must for carpeted floors because the smooth sides won't catch
the carpet fibers like a regular drill bit.

11. Back to Top
Find a circuit to supply power
Photo 5: Run the cable
Run plastic-sheathed cable from the floor outlet to the power source. See the guidelines in the
next step for drilling and stapling the cable.
Most open ceilings have light-fixture boxes and metal or plastic junction boxes where a number
of cables are joined. Both offer potential sources of power for your floor outlet, but a ceiling
light box like the one shown (Photo 9) that's switched with a pull chain rather than a wall switch
is most likely to contain “hot” wires suitable for connecting the floor outlet.
Turn off the circuit breaker or unscrew the fuse that controls the circuit you've chosen. If your
light fixture box is like ours, just turn on the light and have a helper watch it as you switch off
the circuit breakers one at a time until the light goes out. Leave this circuit breaker switched off.
If the electrical junction box you've picked doesn't have a light fixture, you'll have to use a
voltage tester to determine which circuit breaker or fuse to turn off. This process can be complex.
If you don't have electrical experience or are unsure how to do this, don't hesitate to enlist the
help of a licensed electrician.
A word of warning is in order here. Some electrical boxes contain more than one circuit. Before
doing any work in the box, test all the wires in a box with a simple neon voltage tester (Photo 9)
to make sure they're “dead.”
The electrical code requires two additional steps to ensure safety:

12. 1. Determine if the circuit you want to use can handle the additional outlet without
overloading. Do this by shutting off the circuit at the main panel. Then go through the
house turning on lights and other electrical items. Add up the wattage for everything that
doesn't go on, including things that are normally plugged in, such as stereos and
televisions. Then add the wattage of the lamp you'll be plugging into the floor outlet. The
National Electrical Code (NEC) allows a total of 1,800 watts for a 15-amp circuit; 2,400
for a 20-amp circuit. The amp rating of the circuit is printed on the circuit breaker or fuse.
If the total wattage exceeds these amounts, you'll have to find a new circuit. Also, as a
rule of thumb, don't use a circuit if it has any device drawing more than 7.5 amps either
plugged in or directly wired to it.
2. To figure out if there's enough space in the box for the minimum box size required by the
NEC, add: 1 for each hot and neutral wire entering the box, 1 for all the ground wires
combined, 1 for all the clamps combined, and 2 for each device (switch or receptacle)
installed in the box. Multiply this figure by 2 for 14-gauge wire and 2.25 for 12-gauge
wire to get the minimum box volume in cubic inches. Plastic boxes have their volume
stamped inside. Steel box capacities are listed in the electrical code. Call the electrical
inspector for that information. If the box you want to use isn't big enough, add a box
extension or replace the box with a larger one. For more information on sizing an
electrical circuit, seePreventing Electrical Overloads.
CAUTION!
The electrical code prohibits any connections to “dedicated” circuits, such as 20-amp small-
appliance circuits in kitchens and dining areas, 20-amp laundry circuits and 20-amp bathroom
circuits. If you're unsure about your circuit, ask the electrical inspector.
Back to Top
A first-rate electrical job mostly means getting the details right

13. Photo 7: Wire the receptacle
Snip off the wires so they're at least 6 in. long and protrude from the top of the metal box at least
3 in. Strip 5/8 in. of insulation from the black and white wires with a wire stripper. Connect the
bare ground wire to the metal box by looping it once in a clockwise direction around the green
grounding screw and tightening the screw. Loop the end of the same bare grounding wire
clockwise around the grounding screw on the receptacle and tighten the screw. Connect the black
wire to the brass screw and the white wire to the silver screw.
Photos 2, 3 and 4 show how to cut in and install the steel outlet box that's included with the floor
outlet assembly. Mount the box. Then run the cable from your power source to the floor outlet.
Follow these rules if you have to drill through joists.
 Avoid drilling holes in the center one-third of the span or length of the floor joist.
 Holes must be a minimum of 2 in. from the top and bottom edge of the joist. Staple the
cable with special 1/2-in. plastic NM cable staples every 4-1/2 ft. where it runs along the
joist. (TIP: For a neater, easier job, unroll the cable and remove the twists before
installing it.) Don't staple either end of the cable yet, and leave at least 1 ft. of extra cable
on each end.
Photos 6 – 8 show how to wire the new outlet. For more information, see How to Make
Safe Wire Connections.
When the floor outlet connections are complete, move to the basement and connect the
other end of the wires to the power in the ceiling box (Photos 9 and 10). You'll have to
remove a “knockout” plug with a screwdriver or needle-nose pliers to provide a hole for
the cable to enter the box. Attach the cable to the box with a cable clamp. Many boxes
have built-in clamps. Connect the wires as shown in Photo 10. Match the wire connectors
you're using to the number of wires being connected. Red connectors like the ones we're
using can usually connect up to five 14-gauge or four 12-gauge wires, but check the

14. manufacturer's specifications on the package to be sure. Replace the light fixture or cover
plate to complete the wiring job.
For outlet installations on carpeted floors, the top edge of the outlet box must be flush
with the carpet. Flipping the outlet ears over before mounting the box is one easy way to
accomplish this.
Your new floor outlet is strong enough to withstand occasional abuse, and with the cover
and gaskets in place you'll be able to damp-mop the floor without worrying about getting
shocked or damaging the wiring. Keep a record of the manufacturer's name in case you
lose the cover and have to order a new one.
Back to Top
 Tools & Materials
Required Tools for this Project
Have the necessary tools forthis DIYproject lined up before you start—you’llsave time and frustration.
 Cordless drill
 4-in-1 screwdriver
 Needle-nose pliers
 Drill bit set
 Jigsaw
 Voltage tester
 Non-contact voltage tester
 Utility knife
 Wire stripper/cutter
 Wood chisel
Required Materials for this Project
Avoid last-minute shopping tripsby having allyourmaterials ready ahead oftime.Here's a list.
 Electrical cable
 Metalcoat hanger
 Floor boxassembly
 Plastic cable clamps
 Wire connectors
 Plastic staples
 No. 4 x 1/2-in. flathead screws