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OBJECTIVESAfter studying this unit, the student should be able to

• list equipment grounding requirements for bathroom installations.

• draw a wiring diagram for the bathroom and hallway.

• understand Code requirements for receptacles installed in bathrooms.

• understand Code requirements for receptacle outlets in hallways.

• discuss fundamentals of proper lighting for bathrooms.

Lighting Branch-Circuit–Bathrooms, Hallway

Circuit A14 is a 15-ampere branch-circuit that sup-plies the lighting outlets and receptacle outlet in thehallway, and the vanity lighting in both bathrooms.The receptacle outlets in the bathrooms are suppliedby separate circuits A22 and A23. This is a Coderequirement, discussed later in this unit and inUnit 15.

Table 10-1 summarizes outlets and estimatedload for the bathrooms and bedroom hall.

Note that each bathroom shows a ceilingheater/light/fan that is connected to separate circuit

J and K. These are discussed in detail inUnit 22.

A hydromassage tub is located in the bath-room serving the master bedroom. It is connected to a separate circuit A and is also discussed inUnit 22.

The attic exhaust fan in the hall is supplied by aseparate circuit L, also covered in Unit 22.

LIGHTING BRANCH-CIRCUIT A14 FORHALLWAY AND BATHROOMSFigure 10-1 and the electrical plans for this area ofthe home show that each bathroom has a luminaire(fixture) above the vanity mirror. Some typical lumi-naires (fixtures) are shown in Figure 10-2. Ofcourse, the homeowner might decide to purchase amedicine cabinet complete with a self-containedluminaire (lighting fixture). See Figure 10-3, whichillustrates how to rough-in the wiring for each type.These luminaires (fixtures) are controlled by single-pole switches at the doors.

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UNIT 10

Table 10-1 Bathroom and bedroom hall: outlet countand estimated load (Circuit A14). The receptacles inthe master bathroom and hall bathroom are not in-cluded in this table as they are connected to separate20-ampere branch-circuits A22 and A23.

VOLT-DESCRIPTION QUANTITY WATTS AMPERES

Receptacles @ 120 W each 1 120 120

Vanity luminaires (fixtures) @ 200 W each 2 400 400

Hall luminaire (fixture) 010 100 100

TOTALS 4 620 620

236 UNIT 10 Lighting Branch-Circuit—Bathrooms, Hallway

S3

S3S

SS

SS

SSSSS

GFCIJ

K

A14

A11

HEAT–VENT–LIGHT CIRCUIT

HEAT–VENT–LIGHTCIRCUIT

DETAIL OF SWITCHARRANGEMENTIN BATHROOMS

BATHROOMS–HALL

NIGHTLIGHT

LIGHT VANITYLIGHT

HEAT VENT

A12

A22

A23

Figure 10-1 Cable layout for the master bathroom, hall bathroom, and hall. Layout includes lighting Circuit A14,two circuits (A11 and A12) for the heat/vent/lights, and two circuits (A22 and A23) for the receptacles in thebathrooms. The special purpose outlets for the hydromassage tub, attic exhaust fan, and smoke detector arecovered elsewhere in this text.

Figure 10-2 Typical vanity (bathroom) luminaires (lighting fixtures) of the side bracket and strip types. Courtesyof Progress Lighting.

UNIT 10 Lighting Branch-Circuit—Bathrooms, Hallway 237

You must remember that a bathroom (powderroom) should have proper lighting for shaving,combing hair, grooming, and so on. Mirror lightingcan accomplish this, because a mirror will reflectwhat it “sees.” If the face is poorly lit, with shadowson the face, that is precisely what will be reflected inthe mirror.

A luminaire (lighting fixture) directly overheadwill light the top of one’s head, but will cause shad-ows on the face. Mirror lighting and/or adequatelighting above and forward of the standing positionat the vanity can provide excellent lighting in thebathroom. Figure 10-4, Figure 10-5, and Figure 10-6show pictorial as well as section views of typicalsoffit lighting above a bathroom vanity.

Bathroom ReceptaclesThe NEC® in Article 100 defines a bathroom as

“an area including a basin, with one or more of the fol-lowing: a toilet, a tub, or a shower.” See Figure 10-7.

Bathroom receptacles are required to be GFCIprotected per 210.8(A)(1) as discussed in Unit 6.

ºAt least one wall receptacle shall be installedwithin 3 ft (900 mm) of the outside edge of eachbasin, and must be located on a wall or partitionadjacent to the basin, 210.52(D).≠

Receptacles shall not be installed face-up oncounters or work surfaces, 406.4(E).

At least one 20-ampere branch circuit must beprovided for receptacles in bathrooms, 210.11(C)(3).This separate 20-ampere branch-circuit shall not

A B

FRAMED OPENINGFOR RECESSED

MEDICINE CABINET

MOUNT BOX TO PROVIDE ENOUGHCLEARANCE BETWEEN LUMINAIRE(LIGHTING FIXTURE) AND MIRROR

FRAMED OPENING FOR RECESSEDMEDICINE CABINET THAT COMES COMPLETE

WITH A LUMINAIRE (LIGHTING FIXTURE)

BE SURE TO BRING CABLE OR CONDUIT IN AT PROPER LOCATION. IT IS BEST TO

HAVE THE ACTUAL MEDICINE CABINET OR INSTALLATION INSTRUCTIONS TO DETERMINE

EXACT LOCATION OF CABLE KNOCKOUT.

Figure 10-3 Two methods most commonly used for roughing-in the wiring for lighting above a vanity.


RIGHTWRONG

Figure 10-4 Positioning of bathroom luminaires (lighting fixtures). Note the wrong way and the right way toachieve proper lighting.

Figure 10-5 Incandescent soffit lighting. Refer to Unit 7 for minimum clearance Code requirements forinstallation of recessed luminaires (fixtures).

TYPICAL INCANDESCENT RECESSED SOFFIT LIGHTING OVER BATHROOM VANITY

FIXTUREJUNCTION

BOX

END CUTAWAY OF SOFFIT SHOWING RECESSED INCANDESCENT LUMINAIRES (FIXTURES) IN TYPICAL

SOFFIT ABOVE BATHROOM VANITY. TWO OR THREE LUMINAIRES (FIXTURES) GENERALLY INSTALLED TO PROVIDE PROPER LIGHTING.


Figure 10-6 Combination fluorescent and incandescent bathroom lighting.

TYPICAL FLUORESCENT RECESSED SOFFIT LIGHTING OVER BATHROOM VANITY. NOTE ADDITIONAL INCANDESCENT “SIDE-OF-MIRROR” LIGHTING.

F40 SP30/RS/WM

CEMENT BOARD

DRYWALL

END CUTAWAY VIEW OF SOFFIT ABOVE BATHROOM VANITY SHOWING RECESSED

FLUORESCENT LUMINAIRES (FIXTURES) CONCEALED ABOVE TRANSLUCENT ACRYLIC LENS

A

B

C D THIS IS A BATHROOM EVEN THOUGH A DOOR SEPARATES THE AREA INTO TWO PARTS.

THIS IS NOT A BATHROOM.(BASIN ONLY)

THIS IS A BATHROOM.(BASIN, TOILET)

THIS IS A BATHROOM.(BASIN, TOILET, TUB)

Figure 10-7 The Code in Article 100 defines a bathroom as an area including a basin with one or more of thefollowing: a toilet, a tub, or a shower.


supply any other outlets, except that if the circuit supplies a single bathroom, then that 20-amperebranch-circuit is permitted to supply other electricalequipment in the same bathroom. The other equip-ment shall not exceed 10 amperes which is 50 percentof the 20-ampere branch-circuit.

The intent of 210.11(C)(3) is to take bathroomreceptacles off of the lighting branch-circuits inhomes. In many instances, overloads caused byplugging in high-wattage hair dryers and similarhigh-wattage appliances have resulted in total lossof power to that particular branch-circuit.

The present wording of 210.11(C)(3) permitsmore than one bathroom to be connected to the onerequired separate 20-ampere branch-circuit.

In this text, we have chosen to run a separate20-ampere branch-circuit A22 to the receptacle inthe master bedroom bathroom, a separate 20-amperebranch-circuit A23 to the receptacle in the hall bath-room, and another separate 20-ampere branch-circuit B21 to the receptacle in the powder roomlocated near the laundry. These separate circuits areincluded in the general lighting load calculations, sono additional load need be added.

Receptacles in Bathtub andShower Spaces

Because of the obvious hazards associated withwater and electricity, receptacles are not permittedto be installed in bathtub and shower spaces,406.8(C).

GENERAL COMMENTS ON LAMPSAND COLORIncandescent lamps (light bulbs) provide pleasantcolor tones, bringing out the warm red flesh tonessimilar to those of natural light. This is particularlytrue for the “soft” white lamps. Fluorescent lampsavailable today provide a wide range of “coolness”to “warmth.” Rated in degrees Kelvin (i.e., 2500K,3000K, 3500K, 4000K, 5000K, etc.), the lower theKelvin degrees, the “warmer” the color tone. Con-versely, the higher the Kelvin degrees, the “cooler”the color tone. Warm fluorescent lamps bring out thered tones, whereas cool fluorescent lamps tend to givea person’s skin a pale appearance. Thus, you will findmany types of fluorescent lamps, each providing dif-ferent color tones and different efficiencies. Thesemight be marked daylight D (very cool), cool whiteCW (cool), white W (moderate), and warm whiteWW (warm). These categories break down furtherinto a deluxe X series, specification SP series, andspecification deluxe SPX series. Unit 7 of this textdiscusses some basics of lighting. The Instructor’sGuide lists some lamp manufacturers’ publicationsthat cover the subject of lighting in greater detail.

HANGING LUMINAIRES (FIXTURES) IN BATHROOMSNo parts of cord-connected lumnaires (fixtures),hanging lumnaires (fixtures), lighting track, pendants,or ceiling-suspended (paddle) fans shall be locatedwithin a zone measuring 3 ft (900 mm) horizontally

Figure 10-8 No parts of cord-connected luminaires (lightingfixtures), hanging luminaires (fixtures), lighting track, pendants, orceiling-suspended (paddle) fans shall be located above the tub andthe area within 3 ft (900 mm) measured horizontally from the top ofthe bathtub rim (top view), 410.4(D).

3 FT(900 mm)

3 FT(900 mm)

3 FT(900 mm)


and 8 ft (2.5 m) vertically from the top of the bathtubrim, 410.4(D). Figure 10-8 projects the top view ofthe 3 ft (900 mm) restriction. Figure 10-9 shows boththe allowable installation and Code violations of thegiven dimensions. Recessed or surface mountedlumnaires (lighting fixtures) and recessed exhaustfans may be located within the restricted zone.

HALLWAY LIGHTINGThe hallway lighting is provided by one ceiling lum-naire (fixture) that is controlled with two three-wayswitches located at either end of the hall. The home

run to Main Panel A has been brought into this ceil-ing outlet box.

RECEPTACLE OUTLETS IN HALLWAYSOne receptacle outlet has been provided in the hall-way as required in 210.52(H), which states that “forhallways of 10 ft (3 m) or more in length, at leastone receptacle outlet shall be required.”

For the purpose of determining the length of ahallway, the measurement is taken down the center-line of the hall, turning corners if necessary, but notpassing through a doorway, Figure 10-10.

EQUIPMENT GROUNDINGWith few exceptions, equipment with exposed metalparts that could become energized shall begrounded. This includes such things as luminaire(fixtures), in-the-wall and baseboard electricheaters, metal faceplates, medicine cabinets thathave lighting, and similar items. Equipment thatmust be grounded is itemized in 250.110, 250.112and 250.114.

8 FT(2.5 m)

3 FT(900 mm)

CODEVIOLATION

THIS IS OK

8 FT(2.5 m)

3 FT(900 mm)

3 FT(900 mm)

CODEVIOLATIONTHIS IS OK

SUNKENTUB

TUB

Figure 10-9 No parts of cord-connected luminaires(fixtures), hanging luminaires (fixtures), lightingtrack, pendants, or ceiling- suspended (paddle) fansshall be allowed in the shaded areas, 410.4(D).

3 FT 9 IN. (1.14 m)

8 FT

9 IN. (2.67 m

)

Figure 10-10 The centerline measurement of thebedroom hallway in this residence is 12 ft 6 in.(3.81 m), which requires at least one wall receptacleoutlet, 210.52(H). This receptacle may be installedanywhere in the hall. The Code does not specify alocation.

REVIEW

1. List the number and types of switches and receptacles used in Circuit A14.


In general, according to 250.110, all exposednoncurrent-carrying metal parts of electrical equip-ment must be grounded

• if they are within 8 ft (2.5 m) vertically or 5 ft (1.5 m) horizontally of the ground or othergrounded metal objects.

• if the ground and the electrical equipment canbe touched at the same time.

• if they are located in wet or damp locations,such as in bathrooms, showers, and outdoors.

• if they are in electrical contact with metal. Thisrequirement includes such things as metal lath,aluminum foil insulation, and metal sidings.

Equipment is considered grounded when it is properly and permanently connected to metal race-way, the armor of armored cable or metal-clad cable,the equipment grounding conductor in nonmetallic-sheathed cable, or a separate equipment groundingconductor. Of course, the means of grounding (themetal raceway, the armored cable, or the equipmentgrounding conductor in the nonmetallic-sheathedcable) must itself be properly grounded.

A list of cord- and plug-connected appliances in residences that must be grounded is found in 250.114(3). The second paragraph of 250.114 isan exception to the main rule. This exception

accepts “double insulation” or its equivalent in lieuof grounding. Many hand-held appliances, such aselectric drills, electric razors, and electric tooth-brushes, make use of the “double insulation” tech-nique. Such appliances have a two-wire cord andtwo-wire plug cap instead of three-wire cord that hasan equipment grounding conductor and a three-wireplug cap that has a ground prong.

Double-insulated appliances are clearly markedto indicate that they are double insulated.

Immersion Detection CircuitInterrupters

Another way to protect people from electricalshock is to use grooming appliances that are equip-ped with a special attachment plug-cap that is a liq-uid IDCI. IDCIs are discussed in Unit 6.

Switches in Wet LocationsDo not install switches in wet locations, such as

in bathtubs or showers, unless they are part of alisted tub or shower assembly, in which case themanufacturer has taken all of the proper precautions,and submitted the assembly to a recognized testinglaboratory to undergo exhaustive testing to establishthe safety of the equipment. See 404.4.


2. There is a three-way switch in the bedroom hallway leading into the living room.Show your calculation of how to determine the box size for this switch. The boxcontains cable clamps.

3. What wattage was used for each vanity luminaire (fixture) to calculate the estimatedload on Circuit A14? ____________________________________________________

4. What is the current draw for the answer given in question 3?

5. Exposed noncurrent-carrying metallic parts of electrical equipment must be groundedif installed within ___________ ft (___________ m) vertically or ___________ ft (___________ m) horizontally of bathtubs, plumbing fixtures, pipes, or othergrounded metal work or grounded surfaces.

6. What color are the faceplates in the bathrooms? Refer to the specifications.

_____________________________________________________________________

7. Most appliances of the type commonly used in bathrooms, such as hair dryers,electric shavers, and curling irons, have two-wire cords. These appliances are ____________________ insulated or ________ ________ ________ ________protected.

8. a. The NEC ® in section __________ requires that all receptacles in bathrooms be________ protected.

b. The NEC ® in section __________ requires that all receptacles in bathrooms be con-nected to one or more separate 20-ampere branch-circuits that serve no other outlets.

c. The NEC ® in section __________ permits the additional required 20-amperebranch-circuit for bathroom receptacles to supply more than one bathroom.

d. The NEC ® in section __________ permits other electrical equipment to be con-nected to the additional required 20-ampere branch-circuit for bathroom recepta-cles, but only if the branch-circuit supplies a single bathroom and the otherequipment is located in that same bathroom.

e. The NEC ® in section __________ prohibits mounting receptacles in bathroomsface-up in the countertops and work surfaces near basins.

9. Hanging luminaires (lighting fixtures) must be kept at least ________ ft (________ m)from the edge of the tub as measured horizontally. In bathrooms with high ceilings,where the hanging luminaire (fixture) is installed directly over the tub, it must be keptat least _________ ft (_________ m) above the edge of the tub.


10. The following is a layout of a lighting circuit for the bathroom and hallway. Using thecable layout shown in Figure 10-1, make a complete wiring diagram of this circuit.Use colored pencils or pens.

BATHROOMS — HALLWAY

VANITY

VANITY

NOTE:CEILING HEAT/VENT/LIGHT AND RECEPTACLE OUTLET IN BATHROOM NOT ON THIS CIRCUIT. THESE ARE ON CIRCUITS A22 AND A23.

A14


11. Circle the correct answer as to whether a receptacle outlet is required in the followinghallways.

RECEPTACLES

SCALE: 1/4 IN. = 1 FT REQUIRED NOT REQUIREDA

SCALE: 3/8 IN. = 1 FT REQUIRED NOT REQUIREDC

SCALE: 1/8 IN. = 1 FT REQUIRED NOT REQUIREDD

SCALE: 1/2 IN. = 1 FT REQUIRED NOT REQUIREDE

SCALE: 1/4 IN. = 1 FT REQUIRED NOT REQUIREDB

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